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1.
J Bone Miner Res ; 39(4): 417-424, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38477744

RESUMEN

Bone histomorphometric endpoints in transilial biopsies may be associated with an increased risk of atypical femoral fracture (AFF) in patients with osteoporosis who take antiresorptives, including bisphosphonates (BPs). One way to test this hypothesis is to evaluate bone histomorphometric endpoints in age-, gender-, and treatment time-matched patients who either had AFF or did not have AFF. In this study, we performed transiliac bone biopsies in 52 White postmenopausal women with (n = 20) and without (n = 32) AFFs, all of whom had been treated for osteoporosis continuously with alendronate for 4-17 yr. Despite the matched range of treatment duration (4-17 yr), AFF patients received alendronate for significantly longer time (10.7 yr) than non-AFF patients (8.0 yr) (P = .014). Bone histomorphometric endpoints reflecting microstructure and turnover were assessed in cancellous, intracortical, and endocortical envelopes from transilial biopsy specimens obtained from BP-treated patients 3-6 mo after AFF and from non-AFF patients with similar age-, gender-, and range of BP treatment duration. However, in both cancellous and intracortical envelopes, AFF patients had significantly lower wall thickness (W.Th) and higher osteoclast surface (Oc.S/BS) than non-AFF patients. In addition, AFF patients had significantly higher eroded surface (ES/BS) only in the intracortical envelope. None of the dynamic variables related to bone formation and turnover differed significantly between the groups. In conclusion, in the ilium of BP-treated patients with osteoporosis, AFF patients have lower thickness of superficial bone (lower W.Th) of the cancellous and cortical envelopes than non-AFF patients. AFF and non-AFF patients have a similar bone turnover rate in the ilium. Furthermore, in this population, as in previous work, AFF is more likely to occur in BP-treated patients with longer treatment duration.


Bisphosphonates (BPs) are widely used to prevent osteoporotic fracture and treat osteoporosis. However, prolonged use of BPs may increase the risk of atypical femoral fracture (AFF), and their pathogenesis remains unclear. This study compared the bone histomorphometric findings in cancellous and cortical bones between White osteoporotic women with (n = 20) and without AFF (n = 32), who had received BP treatment for a matched duration of 4­17 yr. The BP-treated patients with AFF had significantly lower wall thickness (W.Th) in both cancellous and cortical bones compared to BP-treated patients without AFF. There were no significant differences in bone formation, turnover, or mineral apposition rate between BP-treated AFF and non-AFF patients. In conclusion, our study results suggest that AFF risk is increased in BP-treated patients with smaller young and healthy superficial bone areas (indicated by lower W.Th). Surprisingly, we also discovered that patients with and without AFF have similar bone turnover rates, which contradicts previous beliefs. Our findings provide valuable insights into the potential factors contributing to AFF in BP-treated patients.


Asunto(s)
Fracturas del Fémur , Humanos , Femenino , Fracturas del Fémur/patología , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/inducido químicamente , Anciano , Posmenopausia , Persona de Mediana Edad , Difosfonatos/efectos adversos , Alendronato/efectos adversos , Alendronato/farmacología , Alendronato/uso terapéutico , Blanco
2.
J Clin Ethics ; 35(1): 8-22, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38373334

RESUMEN

AbstractThere is societal consensus that cancer clinical trial participation is unjust because some sociodemographic groups have been systematically underrepresented. Despite this, neither a definition nor an ethical explication for the justice norm of equity has been clearly articulated in this setting, leading to confusion over its application and goals. Herein we define equity as acknowledging sociodemographic circumstances and apportioning resource and opportunity allocation to eliminate disparities in outcomes, and we explore the issues and tensions this norm generates through practical examples. We assess how equality-based enrollment structures in clinical cancer research have perpetuated historical disparities and what equity-based alternatives are necessary to achieve representativeness and an expansive conception of participatory justice in clinical cancer research. This framework addresses the breadth from normative to applied by defining the justice norm of equity and translating it into practical strategies for addressing participation disparities in clinical cancer research.


Asunto(s)
Neoplasias , Justicia Social , Humanos , Neoplasias/terapia , Ensayos Clínicos como Asunto
3.
Haematologica ; 109(4): 1046-1052, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37560812

RESUMEN

Clinical trial eligibility criteria can unfairly exclude patients or unnecessarily expose them to known risks if criteria are not concordant with drug safety. There are few data evaluating the extent to which acute leukemia eligibility criteria are justified. We analyzed criteria and drug safety data for front-line phase II and/or III acute leukemia trials with start dates 1/1/2010-12/31/2019 registered on clinicaltrials.gov. Multivariable analyses assessed concordance between criteria use and safety data (presence of criteria with a safety signal, or absence of criteria without a signal), and differences between criteria and safety-based limits. Of 250 eligible trials, concordant use of ejection fraction criteria was seen in 34.8%, corrected QT level (QTc) in 22.4%, bilirubin in 68.4%, aspartate transaminase/alanine aminotransferase (AST/ALT) in 58.8%, renal function in 68.4%, human immunodeficiency virus (HIV) in 54.8%, and hepatitis B and C in 42.0% and 41.2%. HIV and hepatitis B and C criteria use was concordant with safety data (adjusted Odds Ratios 2.04 [95%CI: 1.13, 3.66], 2.64 [95%CI: 1.38, 5.04], 2.27 [95%CI: 1.20, 4.32]) but organ function criteria were not (all P>0.05); phase III trials were not more concordant. Bilirubin criteria limits were the same as safety-based limits in 16.0% of trials, AST/ALT in 18.1%, and renal function in 13.9%; in 75.7%, 51.4%, and 56.5% of trials, criteria were more restrictive, respectively, by median differences of 0.2, 0.5, and 0.5 times the upper limits of normal. We found limited drug safety justifications for acute leukemia eligibility criteria. These data define criteria use and limits that can be rationally modified to increase patient inclusion and welfare.


Asunto(s)
Infecciones por VIH , Hepatitis B , Leucemia , Humanos , Bilirrubina , Enfermedad Aguda , Leucemia/diagnóstico , Leucemia/tratamiento farmacológico
4.
JBMR Plus ; 5(9): e10523, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34532612

RESUMEN

Atypical femur fractures (AFFs) are well-established serious complication of long-term bisphosphonate and denosumab therapy in patients with osteopenia or osteoporosis. To elucidate underlying mechanism(s) for the development of AFF, we performed a nested case-control study to investigate bone tissue nanomechanical properties and prevailing bone microstructure and tissue-level remodeling status as assessed by bone histomorphometry. We hypothesized that there would be differences in nanomechanical properties between patients with and without AFF and that bone microstructure and remodeling would be related to nanomechanical properties. Thirty-two full-thickness transiliac bone biopsies were obtained from age- and sex-matched patients on long-term bisphosphonate therapy with (n = 16) and without an AFF (n = 16). Standard histomorphometric measurements were made in each sample on three different bone envelopes (cancellous, intracortical, and endosteal). Iliac bone wall thickness was significantly lower on all three bone surfaces in patients with AFF than in those without AFF. Surface-based bone formation rate was suppressed similarly in both groups in comparison to healthy premenopausal and postmenopausal women, with no significant difference between the two groups. Nanoindentation was used to assess material properties of cortical and cancellous bone separately. Elastic modulus was higher in cortical than in cancellous bone in patients with AFF as well as compared to the elastic modulus of cortical bone from non-AFF patients. However, the elastic modulus of the cancellous bone was not different between AFF and non-AFF groups or between cortical and cancellous bone of non-AFF patients. Resistance to plastic deformation was decreased in cortical bone in both AFF and non-AFF groups compared to cancellous bone, but to a greater extent in AFF patients. We conclude that long-term bisphosphonate therapy is associated with prolonged suppression of bone turnover resulting in altered cortical remodeling and tissue nanomechanical properties leading to AFF. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

5.
Exp Cell Res ; 405(1): 112663, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34051242

RESUMEN

BACKGROUND: Hepatic stellate cell (HSC) differentiation/activation is central to liver fibrosis and is innately linked to the immune response to liver injury. Exosomes (EXOs) are important means of communication between cell populations. This study sought to characterize EXO release from HSCs and the effect of HSC-EXOs on macrophage cytokine release/function. METHODS: Liver from a rat fibrosis model was analyzed for EXO expression and localization. Quiescent and culture-activated rat and mouse HSCs and activated human HSCs were analyzed for microRNA expression. Mouse, rat, and human HSCs were culture-activated and EXOs purified from culture medium prior to addition to macrophages, and interleukin-6 (IL-6) and tumor necrosis factor-α (TNFα) mRNA and protein measured. The effect of activated HSC-EXOs on macrophage migration was assayed. RESULTS: Activation of rat HSCs led to increased EXO production in vivo, an effect mirrored by in vitro rat HSC culture-activation. Culture activation of mouse and rat HSCs led to altered EXO microRNA profiles, with a similar microRNA profile detected in activated human HSCs. Addition of activated HSC-EXOs to macrophages stimulated IL-6 and TNFα mRNA expression and protein secretion in mouse and human macrophages, but not for rat HSC-EXO-macrophages. Addition of human EXOs to macrophages stimulated migration, effects mirrored by the direct addition of rhIL-6 and rhTNFα. CONCLUSIONS: HSC-EXOs associate with macrophages and stimulate cytokine synthesis-release and macrophage migration. Constructing a comprehensive understanding of EXO interactions between liver cell populations in the setting of inflammation/fibrosis increases the potential for developing new diagnostic/therapeutic approaches.


Asunto(s)
Exosomas/fisiología , Células Estrelladas Hepáticas/fisiología , Inflamación/inmunología , Macrófagos/inmunología , Animales , Células Cultivadas , Citocinas/metabolismo , Células Estrelladas Hepáticas/citología , Humanos , Inflamación/metabolismo , Inflamación/patología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/metabolismo
6.
Calcif Tissue Int ; 107(6): 543-550, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32814991

RESUMEN

This study has established the normal reference intervals for bone histomorphometric measurements derived from healthy premenopausal women, which is rarely available. We presented the static and dynamic bone histomorphometric data from trans-iliac bone biopsies in 62 healthy premenopausal women (19 blacks and 43 whites, ages 20-53 years). There were no significant differences in age and BMI between black and white women. Since there was no significant difference in bone remodeling between the two ethnic groups, we pooled data of all 62 premenopausal women to establish normal reference intervals for bone histomorphometry. The results provide normal reference intervals for both static and dynamic histomorphometric variables in cancellous and cortical bone of the ilium. None of the bone remodeling-related variables correlated with age or BMI. This study provides reference intervals for bone histomorphometric measurements in both cancellous and cortical bone of the ilium, which would be helpful in the evaluation of bone health in women.


Asunto(s)
Remodelación Ósea , Premenopausia , Adulto , Biopsia , Densidad Ósea , Femenino , Humanos , Ilion , Persona de Mediana Edad , Valores de Referencia , Adulto Joven
7.
BMC Nephrol ; 21(1): 278, 2020 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-32677914

RESUMEN

An amendment to this paper has been published and can be accessed via the original article.

8.
BMC Nephrol ; 21(1): 226, 2020 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-32539845

RESUMEN

BACKGROUND: Focal segmental glomerulosclerosis (FSGS) causes renal fibrosis and may lead to kidney failure. FSGS and its common complication, proteinuria, are challenging to treat. Corticosteroids are ineffective in many patients with FSGS, and alternative treatments often yield suboptimal responses. Repository corticotropin injection (RCI; Acthar® Gel), a naturally sourced complex mixture of purified adrenocorticotropic hormone analogs and other pituitary peptides, may have beneficial effects on idiopathic FSGS via melanocortin receptor activation. METHODS: Two studies in a preclinical (female Sprague-Dawley rats) puromycin aminonucleoside FSGS model assessed the effect of RCI on renal function and morphology: an 8-week comparison of a single RCI dose with methylprednisolone (N = 27), and a 12-week chronic RCI dose range study (N = 34). Primary outcomes were proteinuria and renal pathology improvements for measures of renal fibrosis, tubular damage, glomerular injury, and total kidney injury score. Impact of RCI treatment was also determined by assessing urinary biomarkers for renal injury, podocyte expression of podoplanin (a biomarker for injury), podocyte effacement by electron microscopy, and histological staining for fibrosis biomarkers. RESULTS: Compared with saline treatment, RCI 30 IU/kg significantly reduced proteinuria, with a 38% reduction in peak mean urine protein levels on day 28 in the 8-week model, and RCI 10 IU/kg, 30 IU/kg, and 60 IU/kg reduced peak mean urine protein in the 12-week model by 18, 47, and 44%, respectively. RCI also showed significant dose-dependent improvements in fibrosis, interstitial inflammation, tubular injury, and glomerular changes. Total kidney injury score (calculated from histopathological evaluations) demonstrated statistically significant improvements with RCI 30 IU/kg in the 8-week study and RCI 60 IU/kg in the 12-week study. RCI treatment improved levels of urinary biomarkers of kidney injury (KIM-1 and OPN), expression of podoplanin, and podocyte morphology. RCI also reduced levels of desmin and fibrosis-associated collagen deposition staining. Methylprednisolone did not improve renal function or pathology in this model. CONCLUSIONS: These results provide evidence supporting the improvement of FSGS with RCI, which was superior to corticosteroid treatment in this experimental model. To the authors' knowledge, this is the first evidence that a drug for the treatment of FSGS supports podocyte recovery after repeated injury.


Asunto(s)
Corticoesteroides/uso terapéutico , Hormona Adrenocorticotrópica/administración & dosificación , Glomeruloesclerosis Focal y Segmentaria/tratamiento farmacológico , Riñón/patología , Animales , Biomarcadores/orina , Modelos Animales de Enfermedad , Femenino , Fibrosis , Glomeruloesclerosis Focal y Segmentaria/patología , Glomeruloesclerosis Focal y Segmentaria/fisiopatología , Inyecciones , Riñón/efectos de los fármacos , Riñón/metabolismo , Glicoproteínas de Membrana/metabolismo , Podocitos/patología , Proteinuria/prevención & control , Puromicina Aminonucleósido/farmacología , Ratas , Ratas Sprague-Dawley
9.
PLoS One ; 14(3): e0213766, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30870468

RESUMEN

OBJECTIVE: Healthcare providers have key roles in the prevention of, detection of, and interventions for human trafficking. Yet caring for trafficked persons is particularly challenging: patients whose identities are unknown, unreliable, or false could receive subpar care from providers delivering care in a vacuum of relevant information. The application of precision medicine principles and integration of biometric data (including genetic information) could facilitate patient identification, enable longitudinal medical records, and improve continuity and quality of care for this vulnerable patient population. Scant empirical data exist regarding healthcare system preparedness and care for the needs of this vulnerable population nor data on perspectives on the use and risks of biometrics or genetic information for trafficked patients. METHODS: To address this gap, we conducted mixed-methods research involving semi-structured interviews with key informants, which informed a subsequent broad survey of physicians and registered nurses. RESULTS: Our findings support the perception that trafficked persons obtain care yet remain unnoticed or undocumented in the electronic health record. Our survey findings further reveal that healthcare providers remain largely unaware of human trafficking issues and are inadequately prepared to provide patient-centered care for trafficked and unidentified patients. CONCLUSION: Meaningful efforts to design and implement precision medicine initiatives in an inclusive way that optimizes impacts are unlikely to succeed without concurrent efforts to increase general awareness of and preparedness to care for trafficked persons. Additional research is needed to examine properly the potential utility for biometrics to improve the delivery of care for trafficked patients.


Asunto(s)
Continuidad de la Atención al Paciente/organización & administración , Atención a la Salud/organización & administración , Registros Electrónicos de Salud , Empatía/ética , Personal de Salud/normas , Trata de Personas/psicología , Atención Dirigida al Paciente/normas , Adolescente , Adulto , Anciano , Continuidad de la Atención al Paciente/estadística & datos numéricos , Atención a la Salud/estadística & datos numéricos , Femenino , Personal de Salud/psicología , Necesidades y Demandas de Servicios de Salud , Trata de Personas/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Dig Dis Sci ; 63(3): 653-664, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29330728

RESUMEN

BACKGROUND AND AIM: Hepatitis C virus (HCV)-related cirrhosis, one of the most common etiologies of liver cirrhosis in the Western world, is a risk factor for hepatocellular carcinoma. To confirm and improve current effectiveness of screening and prognosis of patients with established cirrhosis, a credible, simple plasma biomarker is needed. Hepatic stellate cell activation, a pivotal event in cirrhosis development, results in increased secretion of extracellular matrix proteins, including tenascin-C (TnC). Herein, we tested TnC as a simple biomarker to identify cirrhotic patients with active HCV infection from those with HCV eradication. METHODS: A prospective study of subjects with HCV-related cirrhosis, stratified into two groups, HCV or virologic cure, was conducted. Plasma TnC expression was measured by ELISA and Western blots. TnC values were correlated with markers of liver injury and ROC analyses performed between groups. RESULTS: The HCV cirrhotic cohort, consisting mostly of men (56%), Caucasians (76%), and genotype 1a or 1b (84%), was compared to healthy controls (HCs). Plasma TnC was significantly higher in HCV cirrhotic patients with active infection compared to HCs (P < 0.0001) and virologic cure (P < 0.0001). TnC concentrations in virologic cure subjects were not statistically different from HCs. TnC levels correlated with AST, platelets, MELD, APRI, FIB-4, and Child-Pugh score. TnC and AST together were significantly better indicators of cirrhosis in patients with active HCV infection than other markers tested. CONCLUSIONS: TnC and AST provided the best model for discriminating HCV cirrhotics with active infection from HC and virologic cure cohorts over current liver injury markers, suggesting TnC as a potential indicator of ongoing hepatic injury and inflammation.


Asunto(s)
Hepatitis C Crónica/sangre , Hepatitis C Crónica/complicaciones , Cirrosis Hepática/sangre , Cirrosis Hepática/virología , Tenascina/sangre , Adulto , Antivirales/uso terapéutico , Biomarcadores/sangre , Femenino , Hepatitis C Crónica/diagnóstico , Humanos , Cirrosis Hepática/diagnóstico , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos
11.
J Child Adolesc Trauma ; 11(3): 277-288, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32318157

RESUMEN

Examination of novel treatment for complexly traumatized youth, in particular, those exposed to preverbal trauma, is necessary given challenges associated with effective intervention for this population. Therapies that facilitate somatic regulation have demonstrated benefit for some trauma survivors. The current article briefly reviews the emerging literature on symptoms of and treatments for complex and preverbal child trauma and describes Sensory Motor Arousal Regulation Therapy (SMART), an intervention for child and adolescent trauma with preliminary empirical support. SMART aims to enhance sensory motor engagement and promote affective, behavioral and physiological regulation using somatic regulation and sensory integration techniques. Utilizing case study methodology, the article illustrates application of SMART in treatment of a latency-aged child with history of exposure to complex and preverbal traumatic experiences. Case analysis suggests the potential contribution of enhanced somatic regulation in traumatized children toward increased relational engagement, behavioral and emotional regulation, and trauma processing.

12.
Hum Gene Ther ; 29(6): 674-686, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29281894

RESUMEN

Fibrotic liver injury is a significant healthcare burden in the United States. It represents a major cause of morbidity and mortality for which there are no effective Food and Drug Administration-approved treatment strategies. Fibrosis is considered a disruption of the normal wound healing responses mediated by fibroblastic cells, which are triggered and sustained by pro-fibrotic cytokines such as transforming growth factor beta 1 (TGF-ß1). TGF-ß1-mediated trans-differentiation of hepatic stellate cells (HSCs) from quiescent to activated myofibroblasts is a pivotal event in the development of fibrosis. Activation is accompanied by global changes in microRNA (miR) expression. It has been previously reported that miR19b is decreased in activated HSCs and contributes to increased expression of TGF-ß receptor II and connective tissue growth factor, both confirmed targets of miR19b. An adeno-associated virus serotype 2 vector (AAV2) with a miR19b transgene downstream of enhanced green fluorescent protein under the murine collage alpha 1(I) promoter was developed specifically to target HSCs. Male Sprague Dawley rats (250 g) underwent sham or bile-duct ligation (BDL) surgery. Directly after BDL, rats received AAV2-miR19b, AAV2-control, or vehicle normal saline (NS) by portal-vein injection. After 2 weeks, the animals were euthanized, and blood was collected for alanine and aspartate aminotransferase, total and direct bilirubin, and alkaline phosphatase. Tissue was collected for RNA and protein extraction and histology. Fibrosis and measures of hepatic injury were significantly reduced in AAV2-miR19b-treated rats in combination with significant improvements in total and direct bilirubin. Histological analysis of collagen by PicroSirius Red staining revealed a ∼50% reduction compared to AAV2-control or NS-injected animals. Pro-fibrotic markers, smooth-muscle alpha-actin, TGF-ß receptor II, and collagen alpha 2(I) mRNA and protein were significantly decreased compared to AAV2-control and NS groups. AAV2-mediated reintroduction of miR-19b, specifically expressed in HSCs, improved liver function, inhibited fibrosis, and improved measures of hepatic injury in a BDL model.


Asunto(s)
Vectores Genéticos/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/terapia , MicroARNs/metabolismo , Parvovirinae/genética , Serogrupo , Animales , Conductos Biliares/patología , Biomarcadores/metabolismo , Células Cultivadas , Colágeno/genética , Dependovirus , Regulación de la Expresión Génica , Proteínas Fluorescentes Verdes/metabolismo , Células Estrelladas Hepáticas/metabolismo , Ligadura , Hígado/lesiones , Hígado/patología , Macrófagos/metabolismo , Masculino , Ratones , MicroARNs/genética , Neutrófilos/metabolismo , Regiones Promotoras Genéticas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , Transgenes
13.
J Nutr Biochem ; 43: 141-150, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28315617

RESUMEN

Certain dietary components when combined with alcohol exacerbate alcohol-induced liver injury (ALI). Here, we tested whether fructose, a major ingredient of the western diet, enhances the severity of ALI. We fed mice ethanol for 8 weeks in the following Lieber-DeCarli diets: (a) Regular (contains olive oil); (b) corn oil (contains corn oil); (c) fructose (contains fructose and olive oil) and (d) corn+fructose (contains fructose and corn oil). We compared indices of metabolic function and liver pathology among the different groups. Mice fed fructose-free and fructose-containing ethanol diets exhibited similar levels of blood alcohol, blood glucose and signs of disrupted hepatic insulin signaling. However, only mice given fructose-ethanol diets showed lower insulin levels than their respective controls. Compared with their respective pair-fed controls, all ethanol-fed mice exhibited elevated levels of serum ALT; the inflammatory cytokines TNF-α, MCP-1 and MIP-2; hepatic lipid peroxides and triglycerides. All the latter parameters were significantly higher in mice given fructose-ethanol diets than those fed fructose-free ethanol diets. Mice given fructose-free or fructose-containing ethanol diets each had higher levels of hepatic lipogenic enzymes than controls. However, the level of the lipogenic enzyme fatty acid synthase (FAS) was significantly higher in livers of mice given fructose control and fructose-ethanol diets than in all other groups. Our findings indicate that dietary fructose exacerbates ethanol-induced steatosis, oxidant stress, inflammation and liver injury, irrespective of the dietary fat source, to suggest that inclusion of fructose in or along with alcoholic beverages increases the risk of more severe ALI in heavy drinkers.


Asunto(s)
Etanol/efectos adversos , Fructosa/efectos adversos , Hígado/efectos de los fármacos , Hígado/patología , Alanina Transaminasa/sangre , Animales , Autofagia/efectos de los fármacos , Biomarcadores/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Citocromo P-450 CYP2E1/metabolismo , Grasas de la Dieta/farmacología , Inactivación Metabólica , Masculino , Ratones Endogámicos C57BL , Estearoil-CoA Desaturasa/metabolismo , Receptor fas/metabolismo
14.
Data Brief ; 10: 312-314, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27995168

RESUMEN

Our data describe autophagic flux in primary rat hepatic stellate cells (rHSCs) treated with pro-fibrotic growth factor, transforming growth factor beta (TGF-ß). An autophagy flux experiment determines the rate of synthesis and degradation of the autophagosome marker, LC3-II in the presence and absence of the lysosomal inhibitor bafilomcyin, which blocks LC3-II degradation in lysosomes. The effects of a test agent on LC3-II flux through the autophagic pathway is determined immunochemically by its relative amounts detected in lysates of cells treated with and without bafilomycin. This measurement helps to validate whether exposure to an agent affects the biogenesis or the degradation of autophagosomes during autophagy, a major macromolecular degrading mechanism in eukaryotic cells. ("Rev-erb Agonist and TGF-ß Similarly Affect Autophagy but Differentially Regulate Hepatic Stellate Cell Fibrogenic Phenotype" (Thomes et al., in press) [1].

15.
Int J Biochem Cell Biol ; 81(Pt A): 137-147, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27840152

RESUMEN

We demonstrated that ligand-activated nuclear receptor Rev-erbα mitigates CCl4-induced liver fibrosis. Rev-erbα is also a novel regulator of autophagy, a crucial eukaryotic catabolic system in which lysosomes degrade substrates for energy generation. In hepatic stellate cells (HSC) autophagy is reportedly required for this purpose to activate HSCs during fibrogenesis. Here, we examined whether pharmacological activation of Rev-erb with its synthetic ligand SR9009 or treatment with the pro-fibrotic cytokine, TGF-ß, each differentially modulate autophagy to regulate the HSC phenotype. We measured the effects of SR9009 on autophagy markers in a CCl4-induced liver fibrosis model. Using primary and immortalized HSCs in vitro, we quantified SR9009 and TGF-ß effects on autophagy flux. Compared with vehicle-treated controls, livers from CCl4-treated mice exhibited lower AMPK, higher P70S6K phosphorylation, elevated P62 and lower levels of ATG proteins, indicating a disruption of autophagosome (AV) formation. SR9009 treatment prevented CCl4-induced P70S6K phosphorylation but did not affect CCl4-induced changes in AMPK, ATG proteins or P62. Analysis of autophagy markers and autophagy flux in primary HSCs or an immortalized human HSC line (LX2), revealed that SR9009 exposure down-regulated AV biogenesis. These events were associated with lower levels of fibrogenic gene expression, P70S6K phosphorylation and HSC proliferation. However, HSC exposure to TGF-ß enhanced fibrogenic gene expression, P70S6K phosphorylation and HSC proliferation, while it simultaneously decelerated AV synthesis. The autophagy activator rapamycin and the autophagy inhibitor wortmannin each decreased HSC activation, P70S6K phosphorylation and HSC proliferation. Furthermore, knock-down of P70S6K using siRNA blocked basal and TGF-ß-induced cell proliferation in human activated LX2. We conclude that SR9009 and TGF-ß both similarly affected autophagy but, differentially regulated HSC fibrogenic phenotype through modulation of P70S6K, which is crucial for cell proliferation and fibrogenesis.


Asunto(s)
Autofagia/efectos de los fármacos , Células Estrelladas Hepáticas/efectos de los fármacos , Cirrosis Hepática/patología , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares/agonistas , Fenotipo , Pirrolidinas/farmacología , Tiofenos/farmacología , Factor de Crecimiento Transformador beta/farmacología , Células 3T3 , Androstadienos/farmacología , Animales , Autofagosomas/efectos de los fármacos , Autofagosomas/metabolismo , Biomarcadores/metabolismo , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Células Estrelladas Hepáticas/citología , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Masculino , Ratones , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Proteínas Quinasas S6 Ribosómicas 70-kDa/antagonistas & inhibidores , Proteínas Quinasas S6 Ribosómicas 70-kDa/deficiencia , Proteínas Quinasas S6 Ribosómicas 70-kDa/genética , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Wortmanina
16.
Am J Surg ; 212(4): 645-648, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27649975

RESUMEN

BACKGROUND: We aimed to develop and implement a laparoscopic skills curriculum in an Ethiopian surgical residency program. We hypothesized that residents would improve with practice. METHODS: We developed a laparoscopic curriculum by adapting existing training models. Six courses were conducted during 2012 and 2013 in a teaching hospital in Ethiopia. Eighty-eight surgical residents participated. Main outcome measures were laboratory task completion times and student survey responses. RESULTS: Students showed improvement in time needed to complete skills tasks with practice. Mean times improved for all 5 tasks (P ≤ .01). Students uniformly reported that the course was valuable. The curriculum is now taught and sustained by local faculty. CONCLUSIONS: The development and implementation of a collaborative and sustainable laparoscopic curriculum is possible in a low-resource environment. Such a curriculum can result in improved laparoscopic expertise, surgical trainee satisfaction, and may increase utilization of laparoscopy.


Asunto(s)
Curriculum , Cirugía General/educación , Ginecología/educación , Internado y Residencia , Laparoscopía/educación , Competencia Clínica , Educación de Postgrado en Medicina , Etiopía , Hospitales de Enseñanza , Humanos
17.
Alcohol Clin Exp Res ; 40(7): 1430-42, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27291156

RESUMEN

BACKGROUND: Exposure to alcohol and its metabolites can initiate hepatic injury and fibrogenesis. Fibrosis is mediated through hepatic stellate cell (HSC) activation, leading to global changes in mRNA and microRNA (miR) expression. miRs are expressed in cells or shuttled to exosomes which can be detected in tissue culture media (TCM) and biological fluids. The mechanisms and function underlying the differential expression and processing of miRs and their downstream effects during hepatic injury remain poorly understood. METHODS: Expression of primary (pri)-miR17-92. and individual members of this cluster, miR17a, 18a, 19a, 20a, 19b, and 92, were examined in primary HSCs and human LX2 cells exposed to alcohol-conditioned media (CM), liver tissue from a rodent model of alcoholic injury, and in exosomes from TCM and plasma of rodent models and patients with alcoholic liver disease (ALD). miR expression was examined in HSCs transduced with an AAV2 vector carrying GFP-miR19b or GFP-control transgene under the collagen promoter. RESULTS: Profibrotic markers were enhanced in primary HSCs and LX2 cells exposed to alcohol-CM, concomitant with decreased miR19b expression and a significant increase in pri-miR17-92. Increased pri-miR17-92 was confirmed in a rodent model of alcohol-induced liver injury. Individual members of the cluster were inversely proportionate in cells and exosomes. AAV2-mediated miR19b overexpression inhibited miR17-92 and altered expression of individual cluster members in cells and exosomes. Expression of individual miR17-92 cluster members in plasma exosomes isolated from patients with ALD was similar to that seen in a rodent model of alcoholic injury and in vitro. CONCLUSIONS: Reintroduction of miR19b inhibits HSC activation and modulates expression of pri-miR17-92 and the inverse expression of individual cluster members in cells and exosomes. Better understanding of miR17-92 processing may provide mechanistic insights into the role of individual miRs and exosomes during hepatic injury, revealing new therapeutic targets.


Asunto(s)
Etanol/farmacología , Exosomas/metabolismo , Hepatopatías Alcohólicas/metabolismo , Hígado/metabolismo , MicroARNs/efectos de los fármacos , Animales , Expresión Génica/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Humanos , Hepatopatías Alcohólicas/sangre , Masculino , MicroARNs/biosíntesis , MicroARNs/sangre , Cultivo Primario de Células , Ratas
18.
J Thorac Cardiovasc Surg ; 151(4): 1191-200.e3, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26769537

RESUMEN

OBJECTIVE: Heart failure is accompanied by up-regulation of transforming growth factor beta signaling, accumulation of collagen and dysregulation of sarcoplasmic reticulum calcium adenosine triphosphatase cardiac isoform 2a (SERCA2a). We examined the fibrotic response in small and large myocardial infarct, and the effect of overexpression of the SERCA2a gene. METHODS: Ischemic cardiomyopathy was induced via creation of large or small infarct in 26 sheep. Animals were divided into 4 groups: small infarct; large infarct with heart failure; gene-treated (large infarct with heart failure followed by adeno-associated viral vector, serotype 1.SERCA2a gene construct transfer by molecular cardiac surgery with recirculating delivery); and control. RESULTS: Heart failure was significantly less pronounced in the gene-treated and small-infarct groups than in the large-infarct group. Expression of transforming growth factor beta signaling components was significantly higher in the large-infarct group, compared with the small-infarct and gene-treated groups. Both the angiotensin II type 1 receptor and angiotensin II were significantly elevated in the small- and large-infarct groups, whereas gene treatment diminished this effect. Active fibrosis with de novo collagen synthesis was evident in the large-infarct group; the small-infarct and gene-treated groups showed less fibrosis, with a lower ratio of de novo to mature collagen. CONCLUSIONS: The data presented provide evidence that progression of fibrosis is mediated through increased transforming growth factor beta and angiotensin II signaling, which is mitigated by increased SERCA2a gene expression.


Asunto(s)
Cardiomiopatías/terapia , Terapia Genética/métodos , Insuficiencia Cardíaca/prevención & control , Infarto del Miocardio/terapia , Miocardio/enzimología , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/biosíntesis , Angiotensina II/metabolismo , Animales , Calcio/metabolismo , Cardiomiopatías/enzimología , Cardiomiopatías/genética , Cardiomiopatías/patología , Cardiomiopatías/fisiopatología , Colágeno/metabolismo , Modelos Animales de Enfermedad , Inducción Enzimática , Fibronectinas/metabolismo , Fibrosis , Insuficiencia Cardíaca/enzimología , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Hemodinámica , Masculino , Infarto del Miocardio/enzimología , Infarto del Miocardio/genética , Infarto del Miocardio/patología , Infarto del Miocardio/fisiopatología , Miocardio/patología , Miofibroblastos/enzimología , Miofibroblastos/patología , Receptor de Angiotensina Tipo 1/metabolismo , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/genética , Ovinos , Factores de Tiempo , Factor de Crecimiento Transformador beta/metabolismo
19.
Am J Pathol ; 186(1): 145-58, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26603137

RESUMEN

Obesity is an independent risk factor for the development of liver fibrosis/cirrhosis and hepatocellular carcinoma (HCC). Tenascin-C (TnC), an extracellular matrix protein, is transiently expressed during tissue injury and plays a role in fibrogenesis and tumorigenesis. However, the mechanistic role of TnC signaling in the development of HCC remains unknown. We developed a diet-induced obesity HCC mouse model and examined TnC expression and liver injury. To determine the cellular mechanism of TnC signaling in promoting inflammation and hepatocyte epithelial-mesenchymal transition and migration, we used primary hepatocytes and hepatoma and macrophage cell lines. Further, to determine whether elevated TnC expression correlated with obesity-associated HCC, we measured plasma TnC in obese patients with various levels of liver injury. Increased tissue inflammation accompanied with elevated hepatic stellate cell-derived TnC and Toll-like receptor 4 expression was observed in the diet-induced obesity HCC animal model. In vitro studies found enhanced Toll-like receptor 4 signaling activated by TnC, promoting an increased inflammatory response, hepatocyte transformation, and migration. Further, obese patients with cirrhosis alone and in combination with HCC showed significant increases in plasma TnC compared with healthy volunteers and patients with less severe liver injury. Overall, these studies suggest TnC/Toll-like receptor 4 signaling as an important regulator in HCC; inhibiting this signaling axis may be a viable therapeutic target for impeding HCC.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Obesidad/complicaciones , Tenascina/metabolismo , Receptor Toll-Like 4/metabolismo , Adulto , Animales , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/patología , Línea Celular , Dieta , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Técnica del Anticuerpo Fluorescente , Células Estrelladas Hepáticas/metabolismo , Humanos , Immunoblotting , Inmunohistoquímica , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Obesidad/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal/fisiología
20.
Am J Surg ; 210(3): 417-23, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26003202

RESUMEN

BACKGROUND: Local pancreatic head resection (LPHR) for chronic pancreatitis has had limited adoption in the United States perhaps because of sparse outcomes and quality of life data. METHODS: Forty-four patients underwent LPHR and retrospective evaluation of patient outcomes and quality of life assessment was performed. RESULTS: The mean age was 49 ± 11 years (50% men) with chronic alcohol use as the etiology in 79% of patients. One patient (2%) died within 90 days. The intensive care unit stay was 1.8 ± 3.1 days and postoperative length of stay was 12.6 ± 9.4 days with 96% of patients discharged home. Ten (22%) patients had major perioperative complications. Biliary stricture was the most common late complication (14%). Quality of life assessment results showed that global status (47/100) and physical (66/100), cognitive (68/100), and social (52/100) functions were acceptable. Prevalent postoperative symptoms were pain (52/100), insomnia (56/100), and digestive disturbance (60/100). CONCLUSIONS: LPHR is safe and effective for a substantial proportion of patients with chronic pancreatitis. Further refinement in the selection of patients most likely to benefit from this operation is warranted.


Asunto(s)
Páncreas/cirugía , Pancreatitis Crónica/cirugía , Calidad de Vida , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos
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