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1.
Clin Radiol ; 79(3): e369-e375, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38071103

RESUMEN

AIM: To explore the use of quantitative susceptibility mapping (QSM) in assessing changes in brain iron deposits and their association with cognitive function in patients with minimal hepatic encephalopathy (MHE). MATERIALS AND METHODS: The study cohort comprised 27 cases with hepatitis B-associated cirrhosis with MHE (MHE group), 25 with hepatitis B-associated cirrhosis without MHE (NMHE group), and 25 healthy controls (HC group). Iron deposits in the bilateral frontal white matter, caudate nucleus (CN), putamen, globus pallidus, thalamus, red nucleus, substantia nigra (SN), hippocampus, and dentate nucleus were measured by QSM. The associations between iron deposition with the time taken to complete number connection tests A (NCT-A) and the score on digital-symbol test (DST) were analysed. RESULTS: Susceptibility values differed significantly in the bilateral CN, left thalamus, right SN, and left hippocampus in the MHE group compared with the other groups and were positively associated with the times taken to complete the NCT-A in the bilateral CN, left thalamus, and right SN and negatively associated with DST scores in the bilateral CN, left TH, and left HP. CONCLUSION: Reduced cognitive function in MHE patients was significantly associated with abnormally increased iron deposition in certain brain areas. The quantification of brain iron deposition by QSM may thus be an objective and accurate means of evaluating MHE.


Asunto(s)
Encefalopatía Hepática , Hepatitis B , Humanos , Encefalopatía Hepática/diagnóstico por imagen , Encefalopatía Hepática/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen por Resonancia Magnética , Mapeo Encefálico , Cirrosis Hepática/patología , Hierro
2.
Oncogene ; 40(18): 3331-3346, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33850265

RESUMEN

Mutations in the epidermal growth factor receptor (EGFR) tyrosine kinase domain constitutively activate EGFR resulting in lung tumorigenesis. Activated EGFR modulates downstream signaling by altering phosphorylation-driven interactions that promote growth and survival. Secretory carrier membrane proteins (SCAMPs) are a family of transmembrane proteins that regulate recycling of receptor proteins, including EGFR. The potential role of SCAMPs in mutant EGFR function and tumorigenesis has not been elucidated. Using quantitative mass-spectrometry-based phosphoproteomics, we identified SCAMP3 as a target of mutant EGFRs in lung adenocarcinoma and sought to further investigate the role of SCAMP3 in the regulation of lung tumorigenesis. Here we show that activated EGFR, either directly or indirectly phosphorylates SCAMP3 at Y86 and this phosphorylation increases the interaction of SCAMP3 with both wild-type and mutant EGFRs. SCAMP3 knockdown increases lung adenocarcinoma cell survival and increases xenograft tumor growth in vivo, demonstrating a tumor suppressor role of SCAMP3 in lung tumorigenesis. The tumor suppressor function is a result of SCAMP3 promoting EGFR degradation and attenuating MAP kinase signaling pathways. SCAMP3 knockdown also increases multinucleated cells in culture, suggesting that SCAMP3 is required for efficient cytokinesis. The enhanced growth, increased colony formation, reduced EGFR degradation and multinucleation phenotype of SCAMP3-depleted cells were reversed by re-expression of wild-type SCAMP3, but not SCAMP3 Y86F, suggesting that Y86 phosphorylation is critical for SCAMP3 function. Taken together, the results of this study demonstrate that SCAMP3 functions as a novel tumor suppressor in lung cancer by modulating EGFR signaling and cytokinesis that is partly Y86 phosphorylation-dependent.


Asunto(s)
Adenocarcinoma del Pulmón , Receptores ErbB , Humanos , Fosforilación
3.
Cancer Res ; 81(11): 3051-3066, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33727228

RESUMEN

Lung cancer is the leading cause of cancer mortality worldwide. The treatment of patients with lung cancer harboring mutant EGFR with orally administered EGFR tyrosine kinase inhibitors (TKI) has been a paradigm shift. Osimertinib and rociletinib are third-generation irreversible EGFR TKIs targeting the EGFR T790M mutation. Osimertinib is the current standard of care for patients with EGFR mutations due to increased efficacy, lower side effects, and enhanced brain penetrance. Unfortunately, all patients develop resistance. Genomic approaches have primarily been used to interrogate resistance mechanisms. Here we characterized the proteome and phosphoproteome of a series of isogenic EGFR-mutant lung adenocarcinoma cell lines that are either sensitive or resistant to these drugs, comprising the most comprehensive proteomic dataset resource to date to investigate third generation EGFR TKI resistance in lung adenocarcinoma. Unbiased global quantitative mass spectrometry uncovered alterations in signaling pathways, revealed a proteomic signature of epithelial-mesenchymal transition, and identified kinases and phosphatases with altered expression and phosphorylation in TKI-resistant cells. Decreased tyrosine phosphorylation of key sites in the phosphatase SHP2 suggests its inhibition, resulting in subsequent inhibition of RAS/MAPK and activation of PI3K/AKT pathways. Anticorrelation analyses of this phosphoproteomic dataset with published drug-induced P100 phosphoproteomic datasets from the Library of Integrated Network-Based Cellular Signatures program predicted drugs with the potential to overcome EGFR TKI resistance. The PI3K/MTOR inhibitor dactolisib in combination with osimertinib overcame resistance both in vitro and in vivo. Taken together, this study reveals global proteomic alterations upon third generation EGFR TKI resistance and highlights potential novel approaches to overcome resistance. SIGNIFICANCE: Global quantitative proteomics reveals changes in the proteome and phosphoproteome in lung cancer cells resistant to third generation EGFR TKIs, identifying the PI3K/mTOR inhibitor dactolisib as a potential approach to overcome resistance.


Asunto(s)
Adenocarcinoma del Pulmón/tratamiento farmacológico , Resistencia a Antineoplásicos , Imidazoles/farmacología , Fosfoproteínas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteoma/metabolismo , Quinolinas/farmacología , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/patología , Antineoplásicos/farmacología , Apoptosis , Proliferación Celular , Receptores ErbB/antagonistas & inhibidores , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Fosfatidilinositol 3-Quinasas/química , Fosfoproteínas/análisis , Proteoma/análisis , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Células Tumorales Cultivadas
4.
Herz ; 45(4): 362-368, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30054714

RESUMEN

BACKGROUND: The possible treatment strategies for defects of the pace-sense (P/S) part of a defibrillation lead are either implantation of a new high-voltage (HV)-P/S lead, with or without extraction of the malfunctioning lead, or implantation of a P/S lead. METHODS: We conducted a Web-based survey across cardiac implantable electronic device (CIED) centers to investigate their procedural practice and decision-making process in cases of failure of the P/S portion of defibrillation leads. In particular, we focused on the question of whether the integrity of the HV circuit is confirmed by a test shock before decision-making. The questionnaire included 14 questions and was sent to 951 German, 341 Austrian, and 120 Swiss centers. RESULTS: The survey was completed by 183 of the 1412 centers surveyed (12.7% response rate). Most centers (90.2%) do not conduct a test shock to confirm the integrity of the HV circuit before decision-making. Procedural practice in lead management varies depending on the presentation of lead failure and whether the center applies a test shock. In centers that do not conduct a test shock, the majority (69.9%) implant a new HV-P/S lead. Most centers (61.7%) that test the integrity of the HV system implant a P/S lead. The majority of centers favor DF-4 connectors (74.1%) over DF-1 connectors (25.9%) at first CIED implantation. CONCLUSION: Either implanting a new HV-P/S lead or placing an additional P/S lead are selected strategies if the implantable cardioverter-defibrillator lead failure is localized to the P/S portion. However, conducting a test shock to confirm the integrity of the HV component is rarely performed.


Asunto(s)
Desfibriladores Implantables , Cardioversión Eléctrica , Pautas de la Práctica en Medicina , Austria , Alemania , Encuestas y Cuestionarios , Suiza
5.
Sci Adv ; 5(8): eaax2476, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31489377

RESUMEN

Endochondral ossification during long bone development and natural fracture healing initiates by mesenchymal cell condensation, directed by local morphogen signals and mechanical cues. Here, we aimed to mimic development for regeneration of large bone defects. We hypothesized that engineered human mesenchymal condensations presenting transforming growth factor-ß1 (TGF-ß1) and/or bone morphogenetic protein-2 (BMP-2) from encapsulated microparticles promotes endochondral defect regeneration contingent on in vivo mechanical cues. Mesenchymal condensations induced bone formation dependent on morphogen presentation, with BMP-2 + TGF-ß1 fully restoring mechanical function. Delayed in vivo ambulatory loading significantly enhanced the bone formation rate in the dual morphogen group. In vitro, BMP-2 or BMP-2 + TGF-ß1 initiated robust endochondral lineage commitment. In vivo, however, extensive cartilage formation was evident predominantly in the BMP-2 + TGF-ß1 group, enhanced by mechanical loading. Together, this study demonstrates a biomimetic template for recapitulating developmental morphogenic and mechanical cues in vivo for tissue engineering.


Asunto(s)
Desarrollo Óseo/fisiología , Huesos/fisiología , Morfogénesis/fisiología , Osteogénesis/fisiología , Animales , Biomimética/métodos , Huesos/metabolismo , Células Cultivadas , Humanos , Masculino , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/fisiología , Ratas , Ingeniería de Tejidos , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo
7.
Mucosal Immunol ; 10(2): 332-340, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27271317

RESUMEN

Reactive oxygen species (ROS) produced by the phagocyte NADPH oxidase (NOX2) are required for microbial clearance; however, when produced in excess they exacerbate inflammatory response and injure surrounding tissues. NOX2 is a multicomponent enzyme composed of membrane-associated cytochrome b588 and cytosolic components p47phox, p67phox, p40phox, and rac1/2. We investigated whether vasoactive intestinal peptide (VIP), an endogenous immune-modulatory peptide, could affect ROS production by NOX2 in primary human phagocytes. VIP did not modulate basal ROS production by phagocytes, but it inhibited monocyte and not neutrophil ROS production in response to the bacterial peptide N-formyl-methionyl-leucyl-phenylalanine (fMLF). The action of VIP was essentially mediated by high-affinity G-protein coupled receptors VPAC1 as its specific agonist, [ALA11,22,28]VIP, mimicked VIP-inhibitory effect, whereas the specific VPAC1 antagonist, PG97-269, blunted VIP action. Further, we showed that VIP inhibited fMLF-induced phosphorylation of ERK1/2 (extracellular signal-regulated kinase 1/2), p38MAPK (p38 mitogen-activated protein kinase) pathways, and phosphorylation of p47phox on Ser345 residue. Also, VIP exerted an anti-inflammatory effect in a model of carrageenan-induced inflammation in rats. We thus found that VIP exerts anti-inflammatory effects by inhibiting the "MAPK-p47phox phosphorylation-NOX2 activation" axis. These data suggest that VIP acts as a natural anti-inflammatory agent of the mucosal system and its analogs could be novel anti-inflammatory molecules.


Asunto(s)
Antiinflamatorios/uso terapéutico , Edema/terapia , Inflamación/terapia , Monocitos/inmunología , NADPH Oxidasas/metabolismo , Neutrófilos/inmunología , Péptido Intestinal Vasoactivo/uso terapéutico , Animales , Carragenina , Células Cultivadas , Edema/inducido químicamente , Edema/inmunología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Inflamación/inducido químicamente , Inflamación/inmunología , Masculino , Glicoproteínas de Membrana/metabolismo , N-Formilmetionina Leucil-Fenilalanina/inmunología , NADPH Oxidasa 2 , Fosforilación , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal
8.
Leukemia ; 31(1): 75-82, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27416909

RESUMEN

Tyrosine kinase inhibitor (TKI) therapy results in excellent responses in the majority of patients with chronic myeloid leukaemia. First-line imatinib treatment, with selective switching to nilotinib when patients fail to meet specific molecular targets or for imatinib intolerance, results in excellent overall molecular responses and survival. However, this strategy is less effective in cases of primary imatinib resistance; moreover, 25% of patients develop secondary resistance such that 20-35% of patients initially treated with imatinib will eventually experience treatment failure. Early identification of these patients is of high clinical relevance. Since the drug efflux transporter ABCB1 has previously been implicated in TKI resistance, we determined if early increases in ABCB1 mRNA expression (fold change from diagnosis to day 22 of imatinib therapy) predict for patient response. Indeed, patients exhibiting a high fold rise (⩾2.2, n=79) were significantly less likely to achieve early molecular response (BCR-ABL1IS ⩽10% at 3 months; P=0.001), major molecular response (P<0.0001) and MR4.5 (P<0.0001). Additionally, patients demonstrated increased levels of ABCB1 mRNA before the development of mutations and/or progression to blast crisis. Patients with high fold rise in ABCB1 mRNA were also less likely to achieve major molecular response when switched to nilotinib therapy (49% vs 82% of patients with low fold rise). We conclude that early evaluation of the fold change in ABCB1 mRNA expression may identify patients likely to be resistant to first- and second-generation TKIs and who may be candidates for alternative therapy.


Asunto(s)
Mesilato de Imatinib/uso terapéutico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Subfamilia B de Transportador de Casetes de Unión a ATP/análisis , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Células Cultivadas , Resistencia a Antineoplásicos , Expresión Génica , Humanos , Mesilato de Imatinib/farmacología , Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Valor Predictivo de las Pruebas , Pronóstico , Inhibidores de Proteínas Quinasas/farmacología , ARN Mensajero/análisis
9.
Genet Mol Res ; 15(3)2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27525935

RESUMEN

Peanut is one of the most important oil crops worldwide. We used insertion-deletion (InDel) markers to assess the genetic diversity and population structure in cultivated peanut. Fifty-four accessions from North China were genotyped using 48 InDel markers. The markers amplified 61 polymorphic loci with 1 to 8 alleles and an average of 2.6 alleles per marker. The polymorphism information content values ranged from 0.0364 to 0.9030, with an average of 0.5038. Population structure and neighbor-joining (NJ) tree analyses suggested that all accessions could be divided into four clusters (A1-A4), using the NJ method. Likewise, four subpopulations (G1-G4) were identified using STRUCTURE analysis. A principal component analysis was also used and results concordant with the other analysis methods were found. A multi-linear stepwise regression analysis revealed that 13 InDel markers correlated with five measured agronomical traits. Our results will provide important information for future peanut molecular breeding and genetic research.


Asunto(s)
Arachis/genética , ADN de Plantas/genética , Genes de Plantas , Estudios de Asociación Genética , Marcadores Genéticos , Mutación INDEL , Filogenia , Polimorfismo Genético , Análisis de Secuencia de ADN
11.
Oncotarget ; 7(24): 35894-35916, 2016 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-27145285

RESUMEN

AIM: To investigate the use of thermosensitive magnetoliposomes (TMs) loaded with magnetic iron oxide (Fe3O4) and the anti-cancer stem cell marker CD90 (CD90@TMs) to target and kill CD90+ liver cancer stem cells (LCSCs). METHODS: The hepatocellular carcinoma cell line Huh7 was used to separate CD90+ LCSCs by magnetic-activated cell sorting. CD90@TMs was characterized and their ability to target CD90+ LCSCs was determined. Experiments were used to investigate whether CD90@TMs combined with magnetic hyperthermia could effectively eliminate CD90+ LCSCs. RESULTS: The present study demonstrated that CD90+ LCSCs with stem cells properties were successfully isolated. We also successfully prepared CD90@TMs that was almost spherical and uniform with an average diameter of 130±4.6 nm and determined that magnetic iron oxide could be incorporated and retained a superparamagnetic response. CD90@TMs showed good targeting and increased inhibition of CD90+ LCSCs in vitro and in vivo compared to TMs. CONCLUSIONS: CD90@TMs can be used for controlled and targeted delivery of anticancer drugs, which may offer a promising alternative for HCC therapy.


Asunto(s)
Anticuerpos/inmunología , Carcinoma Hepatocelular/inmunología , Neoplasias Hepáticas/inmunología , Células Madre Neoplásicas/inmunología , Antígenos Thy-1/inmunología , Animales , Anticuerpos/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/inmunología , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Separación Inmunomagnética/métodos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Ratones Endogámicos NOD , Ratones SCID , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Temperatura , Antígenos Thy-1/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
13.
Bioresour Technol ; 169: 742-749, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25115598

RESUMEN

Rapid growth in both global energy demand and carbon dioxide emissions associated with the use of fossil fuels has driven the search for alternative sources which are renewable and have a lower environmental impact. This paper reviews the availability and bioenergy potentials of the current biomass feedstocks. These include (i) food crops such as sugarcane, corn and vegetable oils, classified as the first generation feedstocks, and (ii) lignocellulosic biomass derived from agricultural and forestry residues and municipal waste, as second generation feedstocks. The environmental and socioeconomic limitations of the first generation feedstocks have placed greater emphasis on the lignocellulosic biomass, of which the conversion technologies still faces major constraints to full commercial deployment. Key technical challenges and opportunities of the lignocellulosic biomass-to-bioenergy production are discussed in comparison with the first generation technologies. The potential of the emerging third generation biofuel from algal biomass is also reviewed.


Asunto(s)
Biocombustibles , Biomasa , Productos Agrícolas/crecimiento & desarrollo
14.
Curr Opin Biotechnol ; 27: 55-64, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24863897

RESUMEN

Over the last decade there has been a rapid development in culture-independent techniques for exploring microbial communities, which have led to new insights into their structure and function in both natural environments and engineered systems. This review focuses on some of the most important recent advances and their applications to the diverse microbial communities associated with anaerobic digestion. The use of these approaches in combination with complementary imaging techniques, chemical isotope analyses and detailed reactor performance measurements provides a new opportunity to develop a fundamental understanding of how microbial community dynamics, interactions and functionality influence digester efficiency and stability.


Asunto(s)
Reactores Biológicos/microbiología , Metagenómica , Anaerobiosis , Secuencia Conservada , Genoma Bacteriano/genética , Redes y Vías Metabólicas/genética , Metabolómica , Interacciones Microbianas/genética , Proteómica , Transcriptoma
15.
J Laryngol Otol ; 128(2): 174-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24480590

RESUMEN

OBJECTIVE: To describe a case of bilateral superior and posterior semicircular canal dehiscences, and the use of a unilateral transmastoid approach to address both right-sided defects simultaneously. CASE REPORT: In a patient with right-sided hyperacusis, bilateral dehiscence of both the superior and the posterior semicircular canals was identified, located adjacent to the common crus, together with a right-sided, anterosuperiorly positioned sigmoid sinus and a high-riding jugular bulb. Results for audiography and cervical vestibular evoked myogenic potential testing were consistent with right-sided semicircular canal dehiscence. At surgery, a right-sided transmastoid approach provided access to plug both defects simultaneously, following posterior mobilisation of the sigmoid sinus. The patient's hyperacusis was completely resolved, with a 10-30 dB improvement in his right ear air conduction hearing, without decrement in bone conduction. CONCLUSION: In properly selected patients, a transmastoid approach can be used to effectively manage superior semicircular canal dehiscence and posterior semicircular canal dehiscence simultaneously. Pre-operative computed tomography is recommended to evaluate the dehiscence sites and to identify complicating vascular anatomy.


Asunto(s)
Hiperacusia/cirugía , Canales Semicirculares/cirugía , Audiometría , Pérdida Auditiva Sensorineural/etiología , Humanos , Hiperacusia/complicaciones , Hiperacusia/diagnóstico , Hiperacusia/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Canales Semicirculares/patología
16.
Appl Environ Microbiol ; 79(20): 6491-500, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23956388

RESUMEN

This study investigated the process of high-rate, high-temperature methanogenesis to enable very-high-volume loading during anaerobic digestion of waste-activated sludge. Reducing the hydraulic retention time (HRT) from 15 to 20 days in mesophilic digestion down to 3 days was achievable at a thermophilic temperature (55°C) with stable digester performance and methanogenic activity. A volatile solids (VS) destruction efficiency of 33 to 35% was achieved on waste-activated sludge, comparable to that obtained via mesophilic processes with low organic acid levels (<200 mg/liter chemical oxygen demand [COD]). Methane yield (VS basis) was 150 to 180 liters of CH4/kg of VS(added). According to 16S rRNA pyrotag sequencing and fluorescence in situ hybridization (FISH), the methanogenic community was dominated by members of the Methanosarcinaceae, which have a high level of metabolic capability, including acetoclastic and hydrogenotrophic methanogenesis. Loss of function at an HRT of 2 days was accompanied by a loss of the methanogens, according to pyrotag sequencing. The two acetate conversion pathways, namely, acetoclastic methanogenesis and syntrophic acetate oxidation, were quantified by stable carbon isotope ratio mass spectrometry. The results showed that the majority of methane was generated by nonacetoclastic pathways, both in the reactors and in off-line batch tests, confirming that syntrophic acetate oxidation is a key pathway at elevated temperatures. The proportion of methane due to acetate cleavage increased later in the batch, and it is likely that stable oxidation in the continuous reactor was maintained by application of the consistently low retention time.


Asunto(s)
Acetatos/metabolismo , Biota , Methanosarcinaceae/aislamiento & purificación , Aguas del Alcantarillado/microbiología , Anaerobiosis , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Methanosarcinaceae/clasificación , Methanosarcinaceae/fisiología , Oxidación-Reducción , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Temperatura
18.
J Vet Pharmacol Ther ; 34(2): 142-52, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21395605

RESUMEN

Determination and kinetics of enrofloxacin and ciprofloxacin in Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a liquid chromatography/mass spectrometry method. J. vet. Pharmacol. Therap. 34, 142-152. The fluoroquinolones enrofloxacin (EF) and ciprofloxacin (CF) residues were investigated in the edible tissues of two important Asian aquacultured species such as Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry method. Fish and prawn were treated with medicated feed with multiple doses of EF, in field conditions. A validation study of the analytical method was realized in terms of linearity, specificity, precision (repeatability and within-laboratory reproducibility), recovery and decision limit (CCα). The time needed before the antibiotic disappears from animal tissues or reach the maximum residue limit (MRL, 100µg/kg) was assessed. The concentration values of EF detected in Tra catfish tissue were between the MRL and 2×MRL concentrations, according to the fish density, 7days following the end of the enrofloxacin treatment (20mg/kg body weight per day, for seven consecutive days). The concentration value of ER in prawn tissue was lower than the MRL and the limit of quantification (LOQ, 14µg/kg) 5 and 7days after the stop of the EF treatment (50mg/kg body weight per day, for five consecutive days), respectively. The mean detected levels of CF was much lower in comparison with that of EF, indicating that only a small part of EF is metabolized into CF (<5%) in both Tra catfish and prawn.


Asunto(s)
Antiinfecciosos/farmacocinética , Bagres/metabolismo , Ciprofloxacina/farmacocinética , Residuos de Medicamentos/análisis , Fluoroquinolonas/farmacocinética , Palaemonidae/metabolismo , Administración Oral , Alimentación Animal , Animales , Cromatografía Liquida/veterinaria , Ciprofloxacina/análisis , Enrofloxacina , Fluoroquinolonas/análisis , Agua Dulce , Espectrometría de Masas/veterinaria
19.
Leukemia ; 24(10): 1719-24, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20811403

RESUMEN

Around 40-50% of patients with chronic myeloid leukemia (CML) who achieve a stable complete molecular response (CMR; undetectable breakpoint cluster region-Abelson leukemia gene human homolog 1 (BCR-ABL1) mRNA) on imatinib can stop therapy and remain in CMR, at least for several years. This raises the possibility that imatinib therapy may not need to be continued indefinitely in some CML patients. Two possible explanations for this observation are (1) CML has been eradicated or (2) residual leukemic cells fail to proliferate despite the absence of ongoing kinase inhibition. We used a highly sensitive patient-specific nested quantitative PCR to look for evidence of genomic BCR-ABL1 DNA in patients who sustained CMR after stopping imatinib therapy. Seven of eight patients who sustained CMR off therapy had BCR-ABL1 DNA detected at least once after stopping imatinib, but none has relapsed (follow-up 12-41 months). BCR-ABL1 DNA levels increased in all of the 10 patients who lost CMR soon after imatinib cessation, whereas serial testing of patients in sustained CMR showed a stable level of BCR-ABL1 DNA. This more sensitive assay for BCR-ABL1 provides evidence that even patients who maintain a CMR after stopping imatinib may harbor residual leukemia. A search for intrinsic or extrinsic (for example, immunological) causes for this drug-free leukemic suppression is now indicated.


Asunto(s)
Antineoplásicos/uso terapéutico , ADN de Neoplasias/genética , Proteínas de Fusión bcr-abl/genética , Enfermedad Injerto contra Huésped/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Piperazinas/uso terapéutico , Reacción en Cadena de la Polimerasa/métodos , Pirimidinas/uso terapéutico , Adulto , Anciano , Benzamidas , Femenino , Estudios de Seguimiento , Enfermedad Injerto contra Huésped/prevención & control , Humanos , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Masculino , Persona de Mediana Edad , Inducción de Remisión , Sensibilidad y Especificidad , Tasa de Supervivencia , Resultado del Tratamiento
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