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1.
Ann Oncol ; 35(1): 98-106, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37871701

RESUMEN

BACKGROUND: Treatment options are limited for patients with high-risk non-muscle-invasive bladder cancer (NMIBC) with disease recurrence after bacillus Calmette-Guérin (BCG) treatment and who are ineligible for/refuse radical cystectomy. FGFR alterations are commonly detected in NMIBC. We evaluated the activity of oral erdafitinib, a selective pan-fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor, versus intravesical chemotherapy in patients with high-risk NMIBC and select FGFR3/2 alterations following recurrence after BCG treatment. PATIENTS AND METHODS: Patients aged ≥18 years with recurrent, BCG-treated, papillary-only high-risk NMIBC (high-grade Ta/T1) and select FGFR alterations refusing or ineligible for radical cystectomy were randomized to 6 mg daily oral erdafitinib or investigator's choice of intravesical chemotherapy (mitomycin C or gemcitabine). The primary endpoint was recurrence-free survival (RFS). The key secondary endpoint was safety. RESULTS: Study enrollment was discontinued due to slow accrual. Seventy-three patients were randomized 2 : 1 to erdafitinib (n = 49) and chemotherapy (n = 24). Median follow-up for RFS was 13.4 months for both groups. Median RFS was not reached for erdafitinib [95% confidence interval (CI) 16.9 months-not estimable] and was 11.6 months (95% CI 6.4-20.1 months) for chemotherapy, with an estimated hazard ratio of 0.28 (95% CI 0.1-0.6; nominal P value = 0.0008). In this population, safety results were generally consistent with known profiles for erdafitinib and chemotherapy. CONCLUSIONS: Erdafitinib prolonged RFS compared with intravesical chemotherapy in patients with papillary-only, high-risk NMIBC harboring FGFR alterations who had disease recurrence after BCG therapy and refused or were ineligible for radical cystectomy.


Asunto(s)
Neoplasias Vesicales sin Invasión Muscular , Pirazoles , Quinoxalinas , Neoplasias de la Vejiga Urinaria , Humanos , Adolescente , Adulto , Vacuna BCG/efectos adversos , Adyuvantes Inmunológicos/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Invasividad Neoplásica
3.
Rev Sci Instrum ; 90(3): 033705, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30927791

RESUMEN

The polarized neutron imaging technique provides a non-invasive method of characterizing localized magnetic fields inside superconductors. However, complete understanding of the magnetic field distribution has yet to be realized experimentally due to the complexity of the interaction between neutron polarization and magnetic field. In this article, we show that a well-defined and controlled magnetic field through the neutron path contributes to simplify the data analysis and makes future quantitative polarized neutron imaging possible. This is demonstrated in a set of experiments that visualize the magnetic field distribution inside and around the superconductors. The experimental results demonstrate that proper guide field setup allows the visualization of the magnetic field expulsion at the surface of the superconductor in the zero-field cooling condition, as well as the magnetic field trapped inside the superconductor under field cooling condition.

4.
J Kidney ; 2(1)2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27066594

RESUMEN

Long-term renal function is compromised in patients receiving deceased donor kidneys which require cold storage exposure prior to transplantation. It is well established that extended cold storage induces renal damage and several labs, including our own, have demonstrated renal mitochondrial damage after cold storage alone. However, to our knowledge, few studies have assessed renal and mitochondrial function after transplantation of rat kidneys exposed to short-term (4 hr) cold storage compared to transplant without cold storage (autotransplantation). Our data reveal that cold storage plus transplantation exacerbated renal and mitochondrial dysfunction when compared to autotransplantation alone.

5.
J Kidney ; 2(1)2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27104220

RESUMEN

Sepsis can provoke kidney injury, which increases mortality. Human and animal studies have documented increased renal oxidative injury and mitochondrial damage during sepsis. However, few studies have attempted to dissect specific renal targets and/or types of oxidative injury using the cecal ligation and puncture (CLP) murine model of sepsis. The purpose of this short communication is to examine the extent of lipid peroxidation within renal mitochondria using CLP and blue native gel electrophoresis which separates intact mitochondrial respiratory complexes. Our results show that CLP induced increased 4-hydroxy-nonenal protein adduction (marker of lipid peroxidation) in renal homogenates and mitochondrial fractions. Blue native gel electrophoresis revealed that respiratory complex III was selectively targeted within mitochondrial fractions. This supports our prior report showing renal complex III inactivation following CLP. Future studies will identify specific renal proteins within complex III that are modified during sepsis to provide mechanistic insight on how mitochondrial respiration is inhibited during sepsis.

6.
Genetics ; 137(1): 5-18, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8056323

RESUMEN

The properties of gene conversion as measured in fungi that generate asci containing all the products of meiosis imply that meiotic recombination initiates at specific sites. The HIS2 gene of Saccharomyces cerevisiae displays a high frequency of gene conversion, indicating that it is a recombination hotspot. The HIS2 gene was cloned and sequenced, and the cloned DNA was used to make several different types of alterations in the yeast chromosome by transformation; these alterations were used to determine the location of the sequences necessary for the high levels of meiotic conversion observed at HIS2. Previous work indicated that the gene conversion polarity gradient is high at the 3' end of the gene, and that the promoter of the gene is not necessary for the high frequency of conversion observed. Data presented here suggest that at least some of the sequences necessary for high levels of conversion at HIS2 are located over 700 bp downstream of the end of the coding region, extend over (at least) several hundred base pairs, and may be quite complex, perhaps involving chromatin structure. Additional data indicate that multiple single base heterologies within a 1-kb interval contribute little to the frequency of gene conversion. This contrasts with other reports about the role of heterologies at the MAT locus.


Asunto(s)
Conversión Génica/genética , Genes Fúngicos , Saccharomyces cerevisiae/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Elementos Transponibles de ADN , ADN de Hongos , Homocigoto , Datos de Secuencia Molecular , Mutagénesis , Mapeo Restrictivo
7.
Free Radic Biol Med ; 30(9): 957-66, 2001 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-11316575

RESUMEN

Previous immunohistochemical studies have demonstrated enhanced appearance of FGF-1 and nitrotyrosine, a footprint of reactive nitrogen species peroxynitrite (ONOO(-)), in human pancreatic adenocarcinoma. We have examined the consequences of constitutive exposure to FGF-1 in nontumorigenic rat ductal epithelial cells (ARIP). ARIP cells were transduced with either a secreted chimera of FGF-1, ARIP(FGF-1), or a control plasmid, 65 RIP(betag). These cells were evaluated for alteration in growth and morphology, responses to ONOO(-) (protein tyrosine nitration/phosphorylation), and in vivo tumor formation. ARIP(FGF-1) cells, in contrast to 65 RIP(betag), demonstrated a transformed morphology, a 2-fold increased growth rate, and enhanced protein tyrosine phosphorylation. Treatment with 150 microM ONOO(-) resulted in 86 and 7% (p <.01) death of ARIP(betag) and ARIP(FGF-1), respectively. Exposure of 65 RIP(betag) cells to ONOO(-) enhanced tyrosine phosphorylation and tyrosine nitration of several polypeptides. Cell signaling by FGF-1 enhanced both phosphorylation and nitration of tyrosine residues in target proteins modified by ONOO(-). ARIP(betag) cells failed to exhibit tumor formation in nude mice, but at d 7 in vivo cells were TUNEL and nitrotyrosine positive and FGF-1 negative. ARIP(FGF-1) cells readily formed tumor nodules, exhibiting features of pancreatic adenocarcinoma and demonstrating FGF-1-positive, nitrotyrosine-positive, and TUNEL-negative epithelium. These results suggest an interdependent role between FGF-1 and ONOO(-) during the development and progression of pancreatic adenocarcinoma.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/farmacología , Neoplasias Pancreáticas/fisiopatología , Animales , Muerte Celular/efectos de los fármacos , Línea Celular , Factor 1 de Crecimiento de Fibroblastos , Factor 2 de Crecimiento de Fibroblastos/genética , Factor 2 de Crecimiento de Fibroblastos/fisiología , Radicales Libres/metabolismo , Humanos , Nitratos/farmacología , Neoplasias Pancreáticas/etiología , Neoplasias Pancreáticas/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Transducción de Señal , Transducción Genética
8.
Free Radic Biol Med ; 31(12): 1603-8, 2001 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11744334

RESUMEN

Endogenous tyrosine nitration and inactivation of manganese superoxide dismutase (MnSOD) has previously been reported to occur during end-stage human renal allograft rejection. In order to determine whether nitration and inactivation of this critical mitochondrial protein might play a contributory role in the onset of transplant rejection, we employed a rodent model of Chronic Allograft Nephropathy (or CAN). Using this model we followed kidney function from 2-52 weeks post-transplant and correlated graft function with levels of nitration in the renal allograft. Tyrosine nitration of both glomerular and tubular structures occurred at 2 weeks post-transplant. At later times (16 weeks) post-transplant, tyrosine nitration appeared to be confined to tubular structures; however glomerular nitration returned at 52 weeks post-transplant. Interestingly, nitration and inactivation of MnSOD occurs prior to the onset of renal dysfunction in this rat model of chronic allograft nephropathy (2 weeks versus 16 weeks post-transplant). Furthermore, we have identified an additional mitochondrial protein, cytochrome c, as being endogenously nitrated during chronic rejection. The kinetics of cytochrome c nitration lagged behind MnSOD nitration and inactivation (4 weeks compared to 2 weeks); suggesting that loss of MnSOD activity likely contributes to elevation of the nitrating species and further nitration of other targets.


Asunto(s)
Mitocondrias/metabolismo , Ácido Peroxinitroso/biosíntesis , Insuficiencia Renal/metabolismo , Trasplante Homólogo/efectos adversos , Tirosina/metabolismo , Animales , Enfermedad Crónica , Grupo Citocromo c/metabolismo , Rechazo de Injerto/patología , Trasplante de Riñón/patología , Mitocondrias/enzimología , Modelos Animales , Ratas , Especies de Nitrógeno Reactivo/biosíntesis , Insuficiencia Renal/etiología , Insuficiencia Renal/patología , Superóxido Dismutasa/metabolismo
9.
Neuropsychologia ; 36(12): 1275-82, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9863681

RESUMEN

Population variation in handedness (a correlate of cerebral dominance for language) is in part genetic and, it has been suggested, its persistence represents a balanced polymorphism with respect to cognitive ability. This hypothesis was tested in a sample of 12,770 individuals in a UK national cohort (the National Child Development Study) by assessing relative hand skill (in a square checking task) as a predictor of verbal, non-verbal, and mathematical ability and reading comprehension at the age of 11 years. Whereas some modest decrements were present in extreme right handers the most substantial deficits in ability were seen close to the point of equal hand skill ('hemispheric indecision'). For verbal ability females performed better than males, but the relationship to relative hand skill was closely similar for the two sexes; for reading comprehension males close to the point of equal hand skill showed greater impairments than females. Analysed by writing hand the relationship of ability to hand skill appeared symmetrical about the point of 'hemispheric indecision'. The variation associated with degrees of dominance may reflect the operation of continuing selection on the gene (postulated to be X-Y linked) by which language evolved and speciation occurred.


Asunto(s)
Logro , Aptitud , Lateralidad Funcional , Desempeño Psicomotor , Adolescente , Adulto , Niño , Estudios de Cohortes , Dislexia/genética , Inglaterra , Femenino , Estudios de Seguimiento , Lateralidad Funcional/genética , Ligamiento Genético/genética , Humanos , Masculino , Cromosoma X , Cromosoma Y
10.
Metabolism ; 30(6): 605-9, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7231197

RESUMEN

The effects of 2.0 g of clofibrate and 15, 20 and 30 g of colestipol on plasma lipid and lipoprotein levels were evaluated in adult patients with Type IIa hyperlipoproteinemia. Clofibrate treatment was associated with decreases in 11.0% in plasma cholesterol. 15.2% in LDL cholesterol, 26.1% in triglycerides, and an 11.3% increase in HDL cholesterol. The reductions in total cholesterol with the various doses of colestipol ranged from 11.9 to 17.8% and reductions in LDL cholesterol ranged from 16.1 to 27.3%. Colestipol treatment was not associated with any significant change in HDL cholesterol levels and minor increases in triglycerides. The addition of clofibrate to patients receiving colestipol resulted in a significant increase in HDL cholesterol and a decrease in triglycerides, but no additional reduction in total or LDL cholesterol.


Asunto(s)
Clofibrato/uso terapéutico , Colestipol/uso terapéutico , Hiperlipoproteinemia Tipo II/tratamiento farmacológico , Lípidos/sangre , Lipoproteínas/sangre , Poliaminas/uso terapéutico , Adulto , Colesterol/sangre , HDL-Colesterol , LDL-Colesterol , Relación Dosis-Respuesta a Droga , Humanos , Hiperlipoproteinemia Tipo II/sangre , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Persona de Mediana Edad , Triglicéridos/sangre
11.
Arch Surg ; 134(3): 245-51, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10088562

RESUMEN

BACKGROUND: Despite recognition of the devastating malignant potential of pancreatic cancer, the exact pathophysiological events contributing to tumor growth, vascular invasiveness, and hepatic metastasis remain to be elucidated. METHODS: Twelve human pancreatic adenocarcinomas were evaluated using immunohistochemical and in situ hybridization techniques for the appearance of the angiogenic and neurogenic growth factors, acidic fibroblast (FGF-1) and basic fibroblast growth factor (FGF-2), and their high-affinity receptors. Since FGF biological processes appear to be regulated by oxidant stress, tumors were examined further for the immunoappearance of inducible nitric oxide synthase (iNOS) and nitrotyrosine. RESULTS: Compared with normal human pancreatic tissue, tumor specimens exhibited varying levels of enhanced staining for FGF ligands and receptors. The increased appearance of FGF-1 and FGF-2 proteins was accompanied by increased detection of messenger RNA encoding each growth factor. In addition, these pancreatic tumors demonstrated the overexpression of iNOS and immunostaining of nitrotyrosine compared with normal pancreatic tissue. CONCLUSIONS: The enhanced expression of FGF and FGF receptors suggests that these polypeptide mitogens may serve as important mediators of growth and of angiogenic and metastatic responses associated with pancreatic tumors, not seen in normal pancreatic tissue. Furthermore, we provide the first indication of increased expression of iNOS and protein tyrosine nitration, thereby predicting the potential involvement of oxidant stress during development and progression of pancreatic adenocarcinoma.


Asunto(s)
Adenocarcinoma/química , Factores de Crecimiento de Fibroblastos/metabolismo , Óxido Nítrico Sintasa/análisis , Neoplasias Pancreáticas/química , Tirosina/análogos & derivados , Adenocarcinoma/metabolismo , Anciano , Anciano de 80 o más Años , Humanos , Inmunohistoquímica , Neoplasias Pancreáticas/metabolismo , Estudios Retrospectivos , Tirosina/análisis
12.
Free Radic Res ; 34(4): 325-36, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11328670

RESUMEN

Manganese superoxide dismutase (MnSOD) is essential for life as dramatically illustrated by the neonatal lethality of mice that are deficient in MnSOD. In addition, mice expressing only 50% of the normal compliment of MnSOD demonstrate increased susceptibility to oxidative stress and severe mitochondrial dysfunction resulting from elevation of reactive oxygen species. Thus, it is important to know the status of both MnSOD protein levels and activity in order to assess its role as an important regulator of cell biology. Numerous studies have shown that MnSOD can be induced to protect against pro-oxidant insults resulting from cytokine treatment, ultraviolet light, irradiation, certain tumors, amyotrophic lateral sclerosis, and ischemia/reperfusion. In addition, overexpression of MnSOD has been shown to protect against pro-apoptotic stimuli as well as ischemic damage. Conversely, several studies have reported declines in MnSOD activity during diseases including cancer, aging, progeria, asthma, and transplant rejection. The precise biochemical/molecular mechanisms involved with this loss in activity are not well understood. Certainly, MnSOD gene expression or other defects could play a role in such inactivation. However, based on recent findings regarding the susceptibility of MnSOD to oxidative inactivation, it is equally likely that post-translational modification of MnSOD may account for the loss of activity. Our laboratory has recently demonstrated that MnSOD is tyrosine nitrated and inactivated during human kidney allograft rejection and human pancreatic ductal adenocarcinoma. We have determined that peroxynitrite (ONOO- ) is the only known biological oxidant competent to inactivate enzymatic activity, to nitrate critical tyrosine residues, and to induce dityrosine formation in MnSOD. Tyrosine nitration and inactivation of MnSOD would lead to increased levels of superoxide and concomitant increases in ONOO- within the mitochondria which, could lead to tyrosine nitration/oxidation of key mitochondrial proteins and ultimately mitochondrial dysfunction and cell death. This article assesses the important role of MnSOD activity in various pathological states in light of this potentially lethal positive feedback cycle involving oxidative inactivation.


Asunto(s)
Mitocondrias/enzimología , Neoplasias/enzimología , Trasplante de Órganos/efectos adversos , Daño por Reperfusión/enzimología , Superóxido Dismutasa/fisiología , Animales , Apoptosis , Humanos , Ratones , Ratones Noqueados , Nitratos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/deficiencia , Superóxidos/metabolismo
13.
Psychol Rep ; 64(2): 391-6, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2710881

RESUMEN

Subjects responded under LAG-5 reinforcement conditions after consuming alcohol in table wine (0.4 g/kg ethanol). For reinforcement (points), a four-response sequence from two buttons was required which differed from the previous five sequences of four responses. In addition, some subjects responded under restricted conditions in which sequences were limited to those of moving a cursor within a 3 x 3 matrix, while other subjects had no such restrictions. Also some subjects worked alone while others were accompanied by an experimenter. Analysis showed that compared to controls, men in the unrestricted condition who received alcohol showed increased uncertainty in responding while comparable women receiving alcohol showed a decrease in uncertainty of responding. The results are discussed in terms of previous work on alcohol and behavioral variability.


Asunto(s)
Consumo de Bebidas Alcohólicas , Condicionamiento Operante/efectos de los fármacos , Etanol/farmacología , Esquema de Refuerzo , Refuerzo Social , Adulto , Bebidas Alcohólicas , Etanol/administración & dosificación , Femenino , Humanos , Masculino , Factores Sexuales , Facilitación Social
14.
Clin Pharmacol Ther ; 96(6): 662-4, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25148376

RESUMEN

Sepsis-induced acute kidney injury (SAKI) is a frequent complication of infant sepsis that approximately doubles the mortality rate. The poor prognosis of these patients is a result of care that is mainly supportive, nontargeted, and usually begun only after symptoms of the systemic inflammatory response syndrome are observed. Preclinical studies from relevant rodent models of SAKI suggest that mitochondria-targeted antioxidants may be a new mode of therapy that could promote recovery.


Asunto(s)
Lesión Renal Aguda/tratamiento farmacológico , Antioxidantes/uso terapéutico , Mitocondrias/efectos de los fármacos , Compuestos Organofosforados/uso terapéutico , Piperidinas/uso terapéutico , Sepsis/complicaciones , Animales , Modelos Animales de Enfermedad , Humanos , Lactante , Ratones , Mitocondrias/metabolismo , Ratas
15.
Rev Sci Instrum ; 83(7): 075101, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22852718

RESUMEN

We report on the in situ polarized (3)He neutron polarization analyzer developed for the time-of-flight Magnetism Reflectometer at the Spallation Neutron Source at Oak Ridge National Laboratory. Using the spin exchange optical pumping method, we achieved a (3)He polarization of 76% ± 1% and maintained it for the entire three-day duration of the test experiment. Based on transmission measurements with unpolarized neutrons, we show that the average analyzing efficiency of the (3)He system is 98% for the neutron wavelength band of 2-5 Å. Using a highly polarized incident neutron beam produced by a supermirror bender polarizer, we obtained a flipping ratio of >100 with a transmission of 25% for polarized neutrons, averaged over the wavelength band of 2-5 Å. After the cell was depolarized for transmission measurements, it was reproducibly polarized and this performance was maintained for three weeks. A high quality polarization analysis experiment was performed on a reference sample of Fe/Cr multilayer with strong spin-flip off-specular scattering. Using a combination of the position sensitive detector, time-of-flight method, and the excellent parameters of the (3)He cell, the polarization analysis of the two-dimensional maps of reflected, refracted, and off-specular scattered intensity above and below the horizon were obtained, simultaneously.

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