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1.
J Dairy Sci ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39122151

RESUMEN

Staphylococcus aureus intramammary infections often leads to clinical and subclinical mastitis in dairy cattle. Prediction of disease evolution and treatment efficacy based on the characteristics of disease-causing strains of S. aureus would significantly improve management of dairy herds. To study the impact of biofilm production and the influence of genetic lineage, we selected S. aureus isolates from the most prevalent Canadian spa types associated with bovine mastitis. Antimicrobial susceptibility in planktonic growth and for bacteria embedded in biofilm was compared. PCR was used to detect the bap gene responsible for atypical biofilm formation. All Canadian spa types from dairy cattle were susceptible to the 8 antimicrobial agents tested. Only strain sa3493 from spa type t267 showed a resistance to pirlimycin. However, bacteria producing larger amounts of biofilms better survived the bactericidal action of antimicrobial agents even when exposed to concentrations 64 folds higher than the minimal inhibitory concentration determined for planktonic cultures. Pirlimycin was more effective on bacteria producing low to moderate levels of biofilm compared with vancomycin or ceftiofur. Antimicrobial agents did not affect the viability of spa types t13401 and t605 that were high biofilm producers. While both these spa types produced high amounts of biofilm, only t605 possessed the bap gene. We also found a close relationship between DIM at sampling and the presence of spa type t605 isolates. These results suggest that detection of S. aureus spa type may help predict the effectiveness of antimicrobial therapy and that some spa types are more likely to be retrieved toward the end of the lactation.

3.
Radiologia (Engl Ed) ; 64(6): 533-541, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36402539

RESUMEN

Fungal lung co-infections associated with COVID-19 may occur in severely ill patients or those with underlying co-morbidities, and immunosuppression. The most common invasive fungal infections are caused by aspergillosis, mucormycosis, pneumocystis, cryptococcus, and candida. Radiologists integrate the clinical disease features with the CT pattern-based approach and play a crucial role in identifying these co-infections in COVID-19 to assist clinicians to make a confident diagnosis, initiate treatment and prevent complications.


Asunto(s)
COVID-19 , Coinfección , Micosis , Neumonía , Humanos , COVID-19/complicaciones , Coinfección/diagnóstico por imagen , Coinfección/complicaciones , Micosis/etiología , Micosis/microbiología , Pulmón/diagnóstico por imagen , Radiólogos
4.
Radiologia (Engl Ed) ; 64(4): 324-332, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36030080

RESUMEN

Artificial Intelligence has the potential to disrupt the way clinical radiology is practiced globally. However, there are barriers that radiologists should be aware of prior to implementing Artificial Intelligence in daily practice. Barriers include regulatory compliance, ethical issues, data privacy, cybersecurity, AI training bias, and safe integration of AI into routine practice. In this article, we summarize the issues and the impact on clinical radiology.


Asunto(s)
Inteligencia Artificial , Radiología , Humanos , Privacidad , Radiólogos
5.
Radiologia ; 64(6): 533-541, 2022.
Artículo en Español | MEDLINE | ID: mdl-35874908

RESUMEN

Fungal lung co-infections associated with COVID-19 may occur in severely ill patients or those with underlying co-morbidities, and immunosuppression. The most common invasive fungal infections are caused by aspergillosis, mucormycosis, pneumocystis, cryptococcus, and candida. Radiologists integrate the clinical disease features with the CT pattern-based approach and play a crucial role in identifying these co-infections in COVID-19 to assist clinicians to make a confident diagnosis, initiate treatment and prevent complications.

6.
Am J Ophthalmol Case Rep ; 23: 101131, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34151045

RESUMEN

PURPOSE: Mantle cell lymphoma is a rare aggressive subtype of non-Hodgkins B cell lymphoma. It typically presents with asymptomatic monoclonal lymphocytosis, lymphadenopathy or bulky extranodal disease. Mantle cell lymphoma rarely affects the central nervous system. We present two cases in which vision loss was the initial symptom of central nervous system involvement by the malignancy. OBSERVATIONS: Both patients initially received high dose intravenous steroids with notable improvement in their vision. CONCLUSIONS AND IMPORTANCE: Early detection and management of optic nerve infiltration by mantle cell lymphoma is essential as it improves visual outcomes and enables prompt management of the patient's systemic disease.

7.
J Neurol ; 267(12): 3565-3577, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32623595

RESUMEN

INTRODUCTION: While monophasic and relapsing forms of myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD) are increasingly diagnosed world-wide, consensus on management is yet to be developed. OBJECTIVE: To survey the current global clinical practice of clinicians treating MOGAD. METHOD: Neurologists worldwide with expertise in treating MOGAD participated in an online survey (February-April 2019). RESULTS: Fifty-two responses were received (response rate 60.5%) from 86 invited experts, comprising adult (78.8%, 41/52) and paediatric (21.2%, 11/52) neurologists in 22 countries. All treat acute attacks with high dose corticosteroids. If recovery is incomplete, 71.2% (37/52) proceed next to plasma exchange (PE). 45.5% (5/11) of paediatric neurologists use IV immunoglobulin (IVIg) in preference to PE. Following an acute attack, 55.8% (29/52) of respondents typically continue corticosteroids for ≥ 3 months; though less commonly when treating children. After an index event, 60% (31/51) usually start steroid-sparing maintenance therapy (MT); after ≥ 2 attacks 92.3% (48/52) would start MT. Repeat MOG antibody status is used by 52.9% (27/51) to help decide on MT initiation. Commonly used first line MTs in adults are azathioprine (30.8%, 16/52), mycophenolate mofetil (25.0%, 13/52) and rituximab (17.3%, 9/52). In children, IVIg is the preferred first line MT (54.5%; 6/11). Treatment response is monitored by MRI (53.8%; 28/52), optical coherence tomography (23.1%; 12/52) and MOG antibody titres (36.5%; 19/52). Regardless of monitoring results, 25.0% (13/52) would not stop MT. CONCLUSION: Current treatment of MOGAD is highly variable, indicating a need for consensus-based treatment guidelines, while awaiting definitive clinical trials.


Asunto(s)
Autoanticuerpos , Inmunoglobulinas Intravenosas , Adulto , Niño , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Glicoproteína Mielina-Oligodendrócito , Plasmaféresis , Encuestas y Cuestionarios
8.
QJM ; 112(10): 827, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31135026
9.
Clin Radiol ; 74(6): 411-417, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30765109

RESUMEN

A new standardised reporting system was introduced recently for coronary computed tomography (CT) angiography interpretation called CAD-RADS (Coronary Artery Disease-Reporting and Data System). Like any other new reporting platform, CAD-RADS has both advantages and disadvantages. Consistency in reporting, better clarity of communication, and more streamlined clinical recommendations are the major strengths of CAD-RADS. It has many limitations such as misinterpretation of CT angiography findings inherent to any CT angiography examination and unique disadvantages like misclassification of abnormalities, potential to misguide the referring physicians by suggesting management based on a single score. In addition, CAD-RADS does not include the details on location and extent of disease in the coronary arteries, coronary anomalies and other cardiac and extra cardiac findings.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Sistemas de Información Radiológica , Humanos , Reproducibilidad de los Resultados
10.
Eur J Neurol ; 26(8): 1137-e75, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30748058

RESUMEN

BACKGROUND AND PURPOSE: Antibodies to myelin oligodendrocyte glycoprotein (MOG) have been identified in both children and adults with demyelination, with a strong association with bilateral or recurrent optic neuritis (ON). However, the full clinical spectrum of this newly described condition is unknown. We sought to describe non-ON inflammatory ophthalmological presentations such as uveitis and optic perineuritis in the context of MOG antibody seropositivity. METHODS: Using a live cell-based assay analysed by flow cytometry, we identified seropositive patients referred for MOG antibody testing in Australasia between 2014 and 2017. We identified four MOG antibody-positive patients with non-ON inflammatory ophthalmological presentations and present their detailed clinical information in this case series. RESULTS: Three patients had uveitis either in association with, or remote from, ON. One patient had optic perineuritis and peripheral ulcerative keratitis. We describe the presentation, examination, investigation findings and clinical course of these four patients. CONCLUSIONS: Recognition of these novel clinical associations may expand the clinical spectrum of MOG antibody-associated presentations. An expedited diagnosis may guide the management of these complex patients.


Asunto(s)
Autoanticuerpos/inmunología , Glicoproteína Mielina-Oligodendrócito/inmunología , Neuritis Óptica/diagnóstico , Uveítis/diagnóstico , Adulto , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuritis Óptica/inmunología , Uveítis/inmunología
12.
J Appl Microbiol ; 124(6): 1425-1440, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29431875

RESUMEN

AIM: Serratia marcescens is an important multidrug-resistant human pathogen. The pathogenicity of S. marcescens mainly depends on the quorum sensing (QS) mechanism, which regulates the virulence factors production and biofilm formation. Hence, targeting QS mechanism in S. marcescens will ultimately pave the way to combat its pathogenicity. Thus, the present study is intended to evaluate the efficacy of Vetiveria zizanioides root extract-mediated silver nanoparticles (AgNPs) as a potent anti-QS and antibiofilm agent against S. marcescens. METHODS AND RESULTS: The AgNPs were synthesized using V. zizanioides aqueous root extract and the physiochemical properties of V. zizanioides-based AgNPs (VzAgNPs) were evaluated using analytical techniques such as ultraviolet-visible absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, dynamic light scattering and scanning and transmission electron microscopic techniques. VzAgNPs were found to attenuate the QS-dependent virulence factors, namely prodigiosin, protease, lipase, exopolysaccharide productions and biofilm formation of S. marcescens, without inhibiting its growth. Further, the transcriptomic analysis confirmed the down-regulation of QS-dependent genes, which encode for the production of virulence factors and biofilm formation. CONCLUSION: The current study confirms VzAgNPs as an ideal anti-QS and antibiofilm agent against S. marcescens. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first approach that validates the anti-QS and antibiofilm potential of phytosynthesized VzAgNPs against the nosocomial pathogen, S. marcescens. As VzAgNPs exhibits potent antivirulent activities, it could be used to treat hospital-acquired S. marcescens infections.


Asunto(s)
Antibacterianos/metabolismo , Biopelículas/efectos de los fármacos , Chrysopogon/química , Infección Hospitalaria/microbiología , Nanopartículas del Metal/química , Serratia marcescens/efectos de los fármacos , Plata/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Biopelículas/crecimiento & desarrollo , Chrysopogon/metabolismo , Humanos , Percepción de Quorum/efectos de los fármacos , Serratia marcescens/genética , Serratia marcescens/fisiología , Plata/química , Plata/metabolismo , Factores de Virulencia/genética , Factores de Virulencia/metabolismo
13.
J Appl Microbiol ; 125(1): 56-71, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29473983

RESUMEN

AIMS: This study aimed to evaluate the antibiofilm potential of phytol and cefotaxime combinations (PCCs) against Acinetobacter baumannii and to elucidate the molecular mechanism of their antibiofilm potential through the transcriptomic approach. METHODS AND RESULTS: Phytol and cefotaxime combination(s) (PCC(s) [160 µg ml-1  + 8 µg ml-1 for microbial type culture collection (MTCC) strain and 160 µg ml-1  + 0.5 µg ml-1 for clinical isolate] effectively inhibited the A. baumannii biofilm formation. Additionally, light, confocal laser scanning and scanning electron microscopic analyses validated the antibiofilm potential of PCCs. Furthermore, PCCs treated A. baumannii cells showed a decreased level of hydrophobicity index compared to their respective controls. Fourier-transform infrared (FT-IR) spectra of exopolysaccharide matrix extracted from PCCs-treated A. baumannii cells showed a visible decrease in absorbance of polysaccharides, nucleic acids and protein regions compared to the spectra of untreated controls. In the blood sensitivity assay, the PCCs-treated A. baumannii plates showed reduced a number of bacterial colonies compared to their control plates. Reduced level of catalase production was also observed in the PCCs treatment compared to their controls. Transcriptomic analysis revealed the downregulation of bfmR, bap, csuA/B, ompA, pgaA, pgaC and katE biofilm virulence genes in both the A. baumannii strains on treatment with PCCs. CONCLUSION: The obtained results of this study indicate that PCCs have potent antibiofilm activity and downregulate the biofilm-related virulence genes expression in A. baumannii. SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the pioneering study, which shows the antibiofilm effect of PCCs against A. baumannii along with their molecular mechanism. The antibiofilm effect of PCCs could be a successful strategy for eradicating infections related to A. baumannii biofilms in nosocomial settings.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Biopelículas/efectos de los fármacos , Cefotaxima/farmacología , Infección Hospitalaria/microbiología , Fitol/farmacología , Acinetobacter baumannii/crecimiento & desarrollo , Acinetobacter baumannii/patogenicidad , Acinetobacter baumannii/ultraestructura , Antibacterianos/farmacología , Biopelículas/crecimiento & desarrollo , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Genes Bacterianos/genética , Humanos , Espectroscopía Infrarroja por Transformada de Fourier
14.
Psychol Med ; 47(12): 2197-2204, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28366174

RESUMEN

BACKGROUND: Socioeconomic difficulties affect the cognitive and emotional development of children. However, the focus of prior studies has largely been on poverty and material hardship. This study expands on the existing literature by examining the impact of familial transient financial difficulties during infancy on long-term cognitive and behavioral outcomes. METHODS: The National Longitudinal Surveys of Youth (79) were used to assess the association between a transient drop in family income by 50% or more (called transient income decline or TID) during the first 3 years of life and later-life Peabody Individual Achievement Math and Reading scores and behavior problem index (BPI) scores (N = 8272-17 348; median assessment age = 9 years). A subsample of matched siblings (N = 2049-4238) was examined to tease out maternal and intra-familial effects. RESULTS: Exposure to TID predicted increased total and externalizing BPI scores (std. coefficients of 0.10 and 0.09, respectively, p < 0.01) in the overall sample. Among matched siblings, exposure to TID predicted increased total, externalizing, and internalizing BPI scores (std. coefficients of 0.27, 0.25, and 0.23, respectively, p < 0.01). CONCLUSION: Familial transient financial difficulties can have long-lasting behavioral effects for infants. The study identifies an early risk factor and at-risk children, thus providing insight into developing early intervention measures for infants to avoid long-term behavioral problems.


Asunto(s)
Rendimiento Académico/estadística & datos numéricos , Conducta Infantil , Renta/estadística & datos numéricos , Problema de Conducta , Niño , Preescolar , Femenino , Humanos , Lactante , Estudios Longitudinales , Masculino , Matemática/estadística & datos numéricos , Hermanos , Estados Unidos/epidemiología , Vocabulario
15.
Spinal Cord ; 55(7): 687-691, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28169292

RESUMEN

STUDY DESIGN: Retrospective cohort studyObjectives:To identify independent risk factors associated with community-associated multidrug-resistant Psedomonas aeruginosa (MDRPA) in a population of veterans with spinal cord injury and disorders (SCI/D). SETTING: A total of 127 Veterans Affairs healthcare facilities. METHODS: Laboratory results from 1 January 2012 to 31 December 2013 were collected, and MDRPA cultures were compared with non-MDRPA cultures. RESULTS: One thousand four hundred forty-one cultures were collected from Veterans with SCI/D, including 227 cultures with MDRPA isolates. Characteristics associated with an increased odds of MDRPA include age 50-64 (adjusted odds ratio (aOR)=1.80, 95% confidence interval (CI)=1.13-2.87), MDRPA culture in the past 365 days (aOR=9.12, 95% CI=5.88-14.15) and carbapenem exposure in the past 90 days (aOR=2.56, 95% CI=1.35-4.87). In contrast, paraplegia was associated with a 53% decreased odds of MDRPA compared with those with tetraplegia (aOR=0.47, 95% CI=0.32-0.69). CONCLUSIONS: Risk factors for community-associated MDRPA include prior history of MDRPA and exposure to carbapenems. Awareness of these factors is important for targeted prevention and treatment of MDRPA in patients with SCI/D.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple , Pseudomonas aeruginosa , Traumatismos de la Médula Espinal/epidemiología , Traumatismos de la Médula Espinal/microbiología , Adolescente , Adulto , Factores de Edad , Anciano , Femenino , Hospitales de Veteranos , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Infecciones por Pseudomonas/complicaciones , Infecciones por Pseudomonas/epidemiología , Pseudomonas aeruginosa/efectos de los fármacos , Estudios Retrospectivos , Factores de Riesgo , Traumatismos de la Médula Espinal/complicaciones , Estados Unidos , United States Department of Veterans Affairs , Veteranos
16.
Prostate Cancer Prostatic Dis ; 20(1): 36-47, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27779203

RESUMEN

BACKGROUND: The suppressor of cytokine signaling 1 (SOCS1) gene is repressed in prostate cancer (PCa) by epigenetic silencing and microRNA miR30d. Increased expression of the SOCS1-targeting miR30d correlates with higher biochemical recurrence, suggesting a tumor suppressor role of SOCS1 in PCa, but the underlying mechanisms are unclear. We have shown that SOCS1 inhibits MET receptor kinase signaling, a key oncogenic pathway in cancer progression. Here we evaluated the role of SOCS1 in attenuating MET signaling in PCa cells and tumor growth in vivo. METHODS: MET-overexpressing human DU145 and PC3 PCa cell lines were stably transduced with SOCS1, and their growth, migration and invasion of collagen matrix were evaluated in vitro. Cells expressing SOCS1 or the control vector were evaluated for tumor growth in NOD.scid.gamma mice as xenograft or orthotopic tumors. RESULTS: HGF-induced MET signaling was attenuated in SOCS1-expressing DU145 and PC3 cells. Compared with vector control cells, SOCS1-expressing cells showed reduced proliferation and impaired migration following HGF stimulation. DU145 and PC3 cells showed marked ability to invade the collagen matrix following HGF stimulation and this was attenuated by SOCS1. As xenografts, SOCS1-expressing PCa cells showed significantly reduced tumor growth compared with vector control cells. In the orthotopic tumor model, SOCS1 reduced the growth of primary tumors and metastatic spread. Intriguingly, the SOCS1-expressing DU145 and PC3 tumors showed increased collagen deposition, associated with increased frequency of myofibroblasts. CONCLUSIONS: Our findings support the tumor suppressor role of SOCS1 in PCa and suggest that attenuation of MET signaling is one of the underlying mechanisms. SOCS1 in PCa cells also appears to prevent the tumor-promoting functions of cancer-associated fibroblasts.


Asunto(s)
Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Células del Estroma/metabolismo , Proteína 1 Supresora de la Señalización de Citocinas/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Colágeno/metabolismo , Metilación de ADN , Modelos Animales de Enfermedad , Epigénesis Genética , Expresión Génica , Factor de Crecimiento de Hepatocito/metabolismo , Xenoinjertos , Humanos , Masculino , Ratones , Invasividad Neoplásica , Metástasis de la Neoplasia , Neoplasias de la Próstata/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Transducción de Señal , Células del Estroma/patología , Proteína 1 Supresora de la Señalización de Citocinas/genética , Carga Tumoral , Microambiente Tumoral
17.
Spinal Cord ; 54(11): 1001-1009, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27001131

RESUMEN

STUDY DESIGN: Retrospective observational study of bacterial susceptibilities in Veterans with SCI/D as compared to a general patient population. OBJECTIVES: The purpose of this project was to evaluate the prevalence and susceptibility of bacteria isolated from spinal cord injury and disorder (SCI/D) patients as compared with a general patient population and determine whether a SCI/D-specific antibiogram, a report of bacterial susceptibilities used to guide empiric antibiotic selection, would be a useful stewardship tool. SETTING: Veterans Affairs Medical Center located in Cook county, IL, USA. METHODS: Microbiology reports from 1 October 2012 to 30 September 2013 were compiled into a SCI/D-specific antibiogram and compared to a non-SCI/D antibiogram. RESULTS: Persons with positive cultures and SCI/D were younger and had a higher Charlson Index as compared to non-SCI/D patients (P<0.0001 for both). Five thousand one hundred and thirty-one unique isolate cultures were evaluated (SCI/D=23.0%). Frequencies of pathogens isolated in SCI/D and non-SCI/D differed. Methicillin-resistant Staphylococcus aureus occurred more frequently in SCI/D (27.8% vs 55.4%; P<0.0001). Gram-negatives had generally lower susceptibilities in SCI/D and a higher frequency of organisms producing extended-spectrum Beta-lactamases (17.6% vs 5.0%; P<0.0001), carbapenem-resistant Enterobacteriaceae (2.4% vs 0.5%; P<0.0001), carbapenem resistance (7.6% vs 2.4%; P<0.0001) and isolates resistant to ⩾3 antibiotic classes (60.7% vs 28.0%; P=0.0001). CONCLUSION: Different pathogens with poorer susceptibilities are isolated in SCI/D. Thus an SCI/D-specific antibiogram reflective of resistance patterns in these patients may increase the appropriateness of empiric antibiotic selection. The frequency of multi-drug resistant organisms in cultures obtained from patients with SCI/D is worrisome.


Asunto(s)
Infecciones Bacterianas/complicaciones , Pruebas de Sensibilidad Microbiana , Traumatismos de la Médula Espinal/etiología , Traumatismos de la Médula Espinal/microbiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Bacterias/aislamiento & purificación , Infecciones Bacterianas/epidemiología , Estudios Transversales , Farmacorresistencia Bacteriana , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Traumatismos de la Médula Espinal/epidemiología , Estadísticas no Paramétricas , Veteranos , Adulto Joven
19.
Oncogene ; 35(32): 4200-11, 2016 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-26725321

RESUMEN

The SOCS1 gene coding for suppressor of cytokine signaling 1 is frequently repressed in hepatocellular carcinoma (HCC), and hence SOCS1 is considered a tumor suppressor in the liver. However, the tumor-suppressor mechanisms of SOCS1 are not yet well understood. SOCS1 is known to inhibit pro-inflammatory cytokine production and signaling and to promote activation of the p53 tumor suppressor. However, we observed that SOCS1-deficient mice developed numerous and large liver tumor nodules following treatment with the hepatocarcinogen diethylnitrosamine (DEN) without showing increased interleukin-6 production or activation of p53. On the other hand, the livers of DEN-treated Socs1-null mice showed elevated levels of p21(CIP1/WAF1) protein (p21). Even though p21 generally functions as a tumor suppressor, paradoxically many cancers, including HCC, are known to express elevated levels of p21 that correlate with poor prognosis. We observed elevated p21 expression also in the regenerating livers of SOCS1-deficient mice and in cisplatin-treated Socs1-null hepatocytes, wherein the p21 protein showed increased stability. We show that SOCS1 interacts with p21 and promotes its ubiquitination and proteasomal degradation. Besides, the DEN-treated livers of Socs1-null mice showed increased nuclear and cytosolic p21 staining, and the latter was associated with growth factor-induced, phosphatidylinositol 3-kinase-dependent phosphorylation of p21 in SOCS1-deficient hepatocytes. Cytosolic p21 is often associated with malignancy and chemo-resistance in many cancers. Accordingly, SOCS1-deficient hepatocytes showed increased resistance to apoptosis that was reversed by shRNA-mediated p21 knockdown. In the regenerating livers of Socs1-null mice, increased p21 expression coincided with elevated cyclinD levels. Correspondingly, SOCS1-deficient hepatocytes showed increased proliferation to growth factor stimulation that was reversed by p21 knockdown. Overall, our findings indicate that the tumor-suppressor functions of SOCS1 in the liver could be mediated, at least partly, via regulation of the expression, stability and subcellular distribution of p21 and its paradoxical oncogenic functions, namely, resistance to apoptosis and increased proliferation.


Asunto(s)
Carcinoma Hepatocelular/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/genética , Oncogenes , Proteína 1 Supresora de la Señalización de Citocinas/metabolismo , Animales , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Citosol/efectos de los fármacos , Citosol/metabolismo , ADN/biosíntesis , Eliminación de Gen , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Estabilidad Proteica , Transporte de Proteínas/efectos de los fármacos , Proteína 1 Supresora de la Señalización de Citocinas/deficiencia , Proteína 1 Supresora de la Señalización de Citocinas/genética , Factor de Crecimiento Transformador alfa/farmacología
20.
Cancer Chemother Pharmacol ; 76(6): 1133-41, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26526983

RESUMEN

PURPOSE: Idelalisib is a novel, potent inhibitor of phosphatidylinositol 3-kinase delta (PI3Kδ), which is prominently expressed in cells of hematopoietic origin. Renal excretion plays a minor role in elimination of idelalisib in humans (~15 % of the dose is excreted in urine). This study evaluated the pharmacokinetics (PK) and safety of idelalisib and GS-563117 (its inactive primary metabolite) in subjects with severe renal impairment and healthy subjects. METHODS: Subjects with severe renal impairment were matched in age, sex, and body mass index with healthy subjects who had normal renal function. Each subject received a single oral dose of idelalisib at 150 mg, and safety assessments and PK analyses were performed. RESULTS: Compared with healthy subjects, the geometric least-squares mean ratio of area under the concentration-time curve from zero to last PK observation (AUC(last)), area under the concentration-time curve from zero to infinity (AUC(inf)), and maximum observed plasma concentration (C(max)) were 127, 127, and 105 % for idelalisib and 124, 124, and 96 % for GS-563117, respectively, in subjects with severe renal impairment. CONCLUSIONS: There were no clinically relevant changes of idelalisib or GS-563117 PK in subjects with severe renal impairment versus matched healthy controls. No relevant relationships were identified between idelalisib or GS-563117 exposures and baseline creatinine clearance. Idelalisib dosing was generally well tolerated with most treatment-emergent adverse events and laboratory abnormalities assessed as grade 1 or 2 in severity. Accordingly, dose adjustments for idelalisib are not necessary in subjects with mild, moderate, or severe renal impairment.


Asunto(s)
Purinas/farmacocinética , Quinazolinonas/farmacocinética , Insuficiencia Renal/tratamiento farmacológico , Insuficiencia Renal/metabolismo , Anciano , Área Bajo la Curva , Fosfatidilinositol 3-Quinasa Clase Ia/metabolismo , Inhibidores Enzimáticos/farmacocinética , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Humanos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Náusea/inducido químicamente , Inhibidores de las Quinasa Fosfoinosítidos-3 , Purinas/efectos adversos , Quinazolinonas/efectos adversos , Insuficiencia Renal/patología , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
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