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1.
Nature ; 554(7691): 207-210, 2018 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-29261643

RESUMEN

GW170817 was the first gravitational-wave detection of a binary neutron-star merger. It was accompanied by radiation across the electromagnetic spectrum and localized to the galaxy NGC 4993 at a distance of 40 megaparsecs. It has been proposed that the observed γ-ray, X-ray and radio emission is due to an ultra-relativistic jet being launched during the merger (and successfully breaking out of the surrounding material), directed away from our line of sight (off-axis). The presence of such a jet is predicted from models that posit neutron-star mergers as the drivers of short hard-γ-ray bursts. Here we report that the radio light curve of GW170817 has no direct signature of the afterglow of an off-axis jet. Although we cannot completely rule out the existence of a jet directed away from the line of sight, the observed γ-ray emission could not have originated from such a jet. Instead, the radio data require the existence of a mildly relativistic wide-angle outflow moving towards us. This outflow could be the high-velocity tail of the neutron-rich material that was ejected dynamically during the merger, or a cocoon of material that breaks out when a jet launched during the merger transfers its energy to the dynamical ejecta. Because the cocoon model explains the radio light curve of GW170817, as well as the γ-ray and X-ray emission (and possibly also the ultraviolet and optical emission), it is the model that is most consistent with the observational data. Cocoons may be a ubiquitous phenomenon produced in neutron-star mergers, giving rise to a hitherto unidentified population of radio, ultraviolet, X-ray and γ-ray transients in the local Universe.

2.
Public Health ; 178: 137-150, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31698136

RESUMEN

OBJECTIVES: Sociodemographic disparities in the incidence and mortality of human papillomavirus (HPV)-associated conditions have been well documented in the pre-HPV vaccine era. It is still unknown if the introduction of routine vaccination has been effective in reducing these prevaccine era inequalities. The purpose of this review was to determine the utilization of sociodemographic variables to assess for disparities in population-level HPV vaccine impact research and to evaluate the current evidence for disparities in the reduction of HPV-associated conditions after vaccine introduction in the United States (US). STUDY DESIGN: A systematic review of the literature from January 2007 through March 2018 was carried out to identify studies evaluating the impact HPV vaccines have had on the rates of HPV infection, genital warts, and cervical dysplasia (cervical intraepithelial neoplasia grades 1+) in the US. An in-depth review was then performed to synthesize these data and to assess the way prior studies have reported and evaluated for potential disparities in the vaccine's impact within various racial, ethnic, and/or socio-economic subgroups of the population. METHODS: Vaccine impact studies measure the change in the population-level burden of disease prelicensure versus postlicensure of the vaccine. We systematically searched PubMed/Medline and Embase, combining search terms related to the HPV vaccine, sentinel surveillance, and HPV-associated conditions. Eligible studies were those with population-level, postvaccine introduction data that were conducted in the US. Finally, a cited reference search was conducted for all included articles using the Web of Science platform that accesses three major citation indexes: Science Citation Index, Social Sciences Citation Index, and Arts and Humanities Citation Index. This allowed us to screen not only the articles that were cited by our final collection of studies but also the articles that used our selected studies as one of their references. The study protocol is registered in PROSPERO (#CRD42018107579). RESULTS: Overall, 23 of the 4139 references retrieved assessed the population-level impact of HPV vaccines between January 1, 2007, and March 29, 2018. Among these, 13 (57%) reported sociodemographic data. Only two articles reported stratified results by sociodemographic factors, thereby allowing assessment for potential disparate impact. One of these studies described differences in the impact of the vaccine by race, ethnicity, and income. CONCLUSION: Although approximately half of the studies that assessed the impact of the HPV vaccine measured sociodemographic characteristics, few presented results in a way that allowed for the identification of potential differences in impact between the relevant subgroups of the population. Determining to what extent, if any, vaccines are reducing known sociodemographic disparities is an important public health priority and an essential step in developing immunization strategies that are beneficial for all.


Asunto(s)
Disparidades en el Estado de Salud , Vacunas contra Papillomavirus/administración & dosificación , Neoplasias del Cuello Uterino/prevención & control , Femenino , Humanos , Narración , Factores Socioeconómicos , Estados Unidos/epidemiología , Neoplasias del Cuello Uterino/epidemiología
3.
Am J Transplant ; 18(12): 2924-2933, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29847022

RESUMEN

The development of de novo donor-specific HLA antibodies (dnDSA) after transplantation is associated with graft failure, mortality, and cost. There is no effective therapeutic intervention to prevent dnDSA or ameliorate associated injury. The aims of this study were to identify specific HLA factors associated with dnDSA development and to propose primary prevention strategies that could reduce the incidence of dnDSA without prohibitively limiting access to transplant. The investigation cohort included heart transplant recipients from 2008 to 2015 (n = 265). HLA typing was performed and HLA antibody testing was undertaken before and after transplantation. HLAMatchmaker analysis was performed for persistent dnDSA to identify potentially more immunogenic eplet differences. Validation was performed in recipients of lung transplants from 2008 to 2013 (n = 433). The majority of recipients with dnDSA had antibodies to identical eplet positions on DQ2 and DQ7. A high-risk epitope mismatch (found in DQA1*05 +  DQB1*02/DQB1*03:01(7)) was associated with a 4.2- and 4.9-fold increased risk of dnDSA in heart and lung recipients respectively. HLA electrostatic potential modeling provided a plausible explanation for this observed immunogenicity. A theoretical allocation algorithm avoiding high-risk epitope mismatches was generated and predicted to reduce dnDSA by up to 72% without additional testing, eplet analysis, or cost.


Asunto(s)
Epítopos/inmunología , Rechazo de Injerto/etiología , Supervivencia de Injerto/inmunología , Antígenos HLA/inmunología , Trasplante de Corazón/efectos adversos , Isoanticuerpos/efectos adversos , Trasplante de Pulmón/efectos adversos , Estudios de Cohortes , Estudios de Seguimiento , Prueba de Histocompatibilidad , Humanos , Complicaciones Posoperatorias , Pronóstico , Asignación de Recursos , Factores de Riesgo , Donantes de Tejidos
4.
Am J Transplant ; 18(1): 113-124, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28898527

RESUMEN

This study evaluated the independent contribution of voriconazole to the development of squamous cell carcinoma (SCC) in lung transplant recipients, by attempting to account for important confounding factors, particularly immunosuppression. This international, multicenter, retrospective, cohort study included adult patients who underwent lung transplantation during 2005-2008. Cox regression analysis was used to assess the effects of voriconazole and other azoles, analyzed as time-dependent variables, on the risk of developing biopsy-confirmed SCC. Nine hundred lung transplant recipients were included. Median follow-up time from transplantation to end of follow-up was 3.51 years. In a Cox regression model, exposure to voriconazole alone (adjusted hazard ratio 2.39, 95% confidence interval 1.31-4.37) and exposure to voriconazole and other azole(s) (adjusted hazard ratio 3.45, 95% confidence interval 1.07-11.06) were associated with SCC compared with those unexposed after controlling for important confounders including immunosuppressants. Exposure to voriconazole was associated with increased risk of SCC of the skin in lung transplant recipients. Residual confounding could not be ruled out because of the use of proxy variables to control for some confounders. Benefits of voriconazole use when prescribed to lung transplant recipients should be carefully weighed versus the potential risk of SCC. EU PAS registration number: EUPAS5269.


Asunto(s)
Antifúngicos/efectos adversos , Carcinoma de Células Escamosas/etiología , Enfermedades Pulmonares/cirugía , Trasplante de Pulmón/efectos adversos , Neoplasias Cutáneas/etiología , Voriconazol/efectos adversos , Adolescente , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Neoplasias Cutáneas/patología , Receptores de Trasplantes , Adulto Joven
5.
Am J Transplant ; 17(9): 2468-2473, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28500691

RESUMEN

Cell-mediated immune responses predict clinical cytomegalovirus (CMV) events but have not been adopted into routine practice due to lack of interventional studies. Our objective was to demonstrate the safety and feasibility of early discontinuation of antivirals based on the real-time measurement of CMV-specific cell-mediated immunity (CMI) in patients with CMV viremia. Transplant patients were enrolled at the onset of CMV viremia requiring antiviral therapy. CD8 T cell responses were determined using the Quantiferon-CMV assay, and results were used to guide subsequent management. A total of 27 patients (median viral load at onset 10 900 International Units/mL) were treated until viral load negative. At end of treatment, 14/27 (51.9%) had a positive CMV-CMI response and had antivirals discontinued. The remaining 13/27 (48.1%) patients had a negative CMV-CMI response and received 2 months of secondary antiviral prophylaxis. In those with a positive CMI and early discontinuation of antivirals, only a single patient experienced a low-level asymptomatic recurrence. In contrast, recurrence was observed in 69.2% of CMI-negative patients despite more prolonged antivirals (p = 0.001). In conclusion, this is the first study to demonstrate the feasibility and safety of real-time CMV-specific CMI assessment to guide changes to the management of CMV infection.


Asunto(s)
Antivirales/uso terapéutico , Infecciones por Citomegalovirus/prevención & control , Inmunidad Celular/inmunología , Trasplante de Riñón/efectos adversos , Trasplante de Hígado/efectos adversos , Trasplante de Pulmón/efectos adversos , Medicina de Precisión , Adulto , Anciano , Anciano de 80 o más Años , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/etiología , Infecciones por Citomegalovirus/patología , ADN Viral/genética , Intervención Médica Temprana , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Linfocitos T/inmunología , Carga Viral
6.
Am J Transplant ; 17(4): 1129-1131, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27873483

RESUMEN

Lung transplantation using RNA+ hepatitis C (HCV+) donors to seronegative recipients is not currently performed due to the very high risk of transmission. Previous reports have shown poor survival when this practice was applied. The emergence of new direct-acting antiviral drugs (DAA) suggests a high chance of sustained virologic response in immunocompetent patients. We report here successful transplantation of lungs from HCV+ donor to HCV- recipient. The recipient was an HCV- patient with chronic lung allograft dysfunction. Viral transmission occurred early posttransplant but excellent clinical outcomes were observed including elimination of HCV after 12 weeks of treatment using DAAs.


Asunto(s)
Supervivencia de Injerto , Hepatitis C/prevención & control , Trasplante de Pulmón/métodos , Donantes de Tejidos , Obtención de Tejidos y Órganos , Receptores de Trasplantes , Adulto , Hepacivirus/fisiología , Hepatitis C/transmisión , Hepatitis C/virología , Humanos , Masculino , Persona de Mediana Edad
7.
Am J Transplant ; 15(4): 993-1002, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25772069

RESUMEN

The growing demand for suitable lungs for transplantation drives the quest for alternative strategies to expand the donor pool. The aim of this study is to evaluate the outcomes of lung transplantation (LTx) with donation after circulatory determination of death (DCDD) and the impact of selective ex vivo lung perfusion (EVLP). From 2007 to 2013, 673 LTx were performed, with 62 (9.2%) of them using DCDDs (seven bridged cases). Cases bridged with mechanical ventilation/extracorporeal life support were excluded. From 55 DCDDs, 28 (51%) underwent EVLP. Outcomes for LTx using DCDDs and donation after neurological determination of death (DNDD) donors were similar, with 1 and 5-year survivals of 85% and 54% versus 86% and 62%, respectively (p = 0.43). Although comparison of survival curves between DCDD + EVLP versus DCDD-no EVLP showed no significant difference, DCDD + EVLP cases presented shorter hospital stay (median 18 vs. 23 days, p = 0.047) and a trend toward shorter length of mechanical ventilation (2 vs. 3 days, p = 0.059). DCDDs represent a valuable source of lungs for transplantation, providing similar results to DNDDs. EVLP seems an important technique in the armamentarium to safely increase lung utilization from DCDDs; however, further studies are necessary to better define the role of EVLP in this context.


Asunto(s)
Circulación Sanguínea , Trasplante de Pulmón , Donantes de Tejidos , Adulto , Femenino , Humanos , Pulmón , Masculino , Persona de Mediana Edad , Perfusión , Pronóstico , Estudios Retrospectivos
8.
Am J Transplant ; 15(2): 417-26, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25612494

RESUMEN

Donor-specific HLA antibodies (DSA) have an adverse effect on short-term and long-term lung transplant outcomes. We implemented a perioperative strategy to treat DSA-positive recipients, leading to equivalent rejection and graft survival outcomes. Pretransplant DSA were identified to HLA-A, B, C, DR and DQ antigens. DSA-positive patients were transplanted if panel reactive antibody (PRA) ≥30% or medically urgent and desensitized with perioperative plasma exchange, intravenous immune globulin, antithymocyte globulin (ATG), and mycophenolic acid (MPA). PRA-positive/DSA-negative recipients received MPA. Unsensitized patients received routine cyclosporine, azathioprine and prednisone without ATG. From 2008-2011, 340 lung-only first transplants were performed: 53 DSA-positive, 93 PRA-positive/DSA-negative and 194 unsensitized. Thirty-day survival was 96 %/99%/96% in the three groups, respectively. One-year graft survival was 89%/88%/86% (p = 0.47). DSA-positive and PRA-positive/DSA-negative patients were less likely to experience any ≥ grade 2 acute rejection (9% and 9% vs. 18% unsensitized p = 0.04). Maximum predicted forced expiratory volume (1 s) (81%/74%/76%, p = NS) and predicted forced vital capacity (81%/77%/78%, respectively, p = NS) were equivalent between groups. With the application of this perioperative treatment protocol, lung transplantation can be safely performed in DSA/PRA-positive patients, with similar outcomes to unsensitized recipients.


Asunto(s)
Desensibilización Inmunológica/métodos , Supervivencia de Injerto/fisiología , Trasplante de Pulmón/mortalidad , Pulmón/fisiología , Atención Perioperativa/métodos , Receptores de Trasplantes , Adulto , Anciano , Suero Antilinfocítico/uso terapéutico , Canadá , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Volumen Espiratorio Forzado/fisiología , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Pulmón/cirugía , Masculino , Persona de Mediana Edad , Ácido Micofenólico/uso terapéutico , Intercambio Plasmático , Estudios Retrospectivos , Resultado del Tratamiento , Capacidad Vital/fisiología
9.
J Antimicrob Chemother ; 70(4): 1064-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25604745

RESUMEN

OBJECTIVES: The most common mechanism of azole (itraconazole and voriconazole) resistance in Aspergillus fumigatus is a mutation at the cyp51A locus. The aim of our study was to determine the rate of cyp51A mutations in lung transplant recipients (LTR) undergoing targeted antifungal prophylaxis with 12 weeks of voriconazole. METHODS: We conducted a prospective study that included 22 LTR with A. fumigatus between October 2008 and November 2011. Of those, 10 LTR were colonized with A. fumigatus and 12 had invasive pulmonary aspergillosis. RESULTS: Four patients were found to have A. fumigatus isolates with a cyp51A mutation, two had colonization and two had invasive pulmonary aspergillosis. The remaining 18 LTR had WT cyp51A A. fumigatus isolates. All A. fumigatus isolates (except one due to mixed growth) were tested for antifungal susceptibility. A total of nine LTR were exposed to azoles prior to A. fumigatus isolation for a median duration of 249 (IQR 99-524) days. Azole exposure preceded the isolation of two mutant isolates and seven WT isolates. None of the cyp51A mutant isolates conferred phenotypic resistance to azoles. CONCLUSIONS: Targeted antifungal prophylaxis in LTR did not lead to cyp51A resistance mutations in this cohort. Data on larger cohorts who receive universal antifungal prophylaxis are needed.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergillus fumigatus/enzimología , Sistema Enzimático del Citocromo P-450/genética , Proteínas Fúngicas/genética , Trasplante de Pulmón , Tasa de Mutación , Aspergilosis Pulmonar/microbiología , Voriconazol/uso terapéutico , Aspergillus fumigatus/genética , Aspergillus fumigatus/aislamiento & purificación , Quimioprevención/métodos , Humanos , Estudios Prospectivos , Receptores de Trasplantes
10.
Am J Transplant ; 14(12): 2749-57, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25358842

RESUMEN

Chronic lung allograft dysfunction (CLAD) is the leading cause of mortality following lung transplantation. We conducted a retrospective cohort study including 397 bilateral lung recipients transplanted in from 1996 to 2009 to determine the association between ambient air pollution, CLAD and mortality. Pollution exposure was assessed using satellite-based estimates of nitrogen dioxide, distance to major roadway and total length of roadways around a patient's home. Cumulative exposures to ozone and particulate matter were estimated from concentrations measured at fixed-site stations near patients' homes using inverse distance weighted interpolation. Cox proportional hazards models were used to estimate the associations of CLAD with air pollution exposure, adjusting for various individual and neighborhood characteristics. During the follow-up, 185 patients developed CLAD (47%) and 101 patients died (25%). Fifty-four deaths (53%) were due to CLAD. We observed an association between CLAD development and road density within 200 m of a patient's home (HR 1.30 [95% CI 1.07-1.58]). Although based on a subgroup of 14 patients, living within 100 m of a highway was associated with a high risk for developing CLAD (HR 4.91 [95% CI 2.22, 10.87]). These data suggest that exposure to traffic-related air pollution is associated with development of CLAD among lung transplant recipients.


Asunto(s)
Contaminación del Aire/efectos adversos , Rechazo de Injerto/etiología , Enfermedades Pulmonares/cirugía , Trasplante de Pulmón , Material Particulado/efectos adversos , Complicaciones Posoperatorias , Adulto , Anciano , Aloinjertos , Femenino , Estudios de Seguimiento , Rechazo de Injerto/diagnóstico , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo
11.
Am J Transplant ; 14(10): 2235-45, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25135579

RESUMEN

With improved survival rates in solid organ transplantation there has been an increased focus on long-term outcomes following transplant, including physical function, health-related quality-of-life and cardiovascular mortality. Exercise training has the potential to affect these outcomes, however, research on the optimal timing, type, dose of exercise, mode of delivery and relevant outcomes is limited. This article provides a summary of a 2-day meeting held in April 2013 (Toronto, Canada) in which a multi-disciplinary group of clinicians, researchers, administrators and patient representatives engaged in knowledge exchange and discussion of key issues in exercise in solid organ transplant (SOT). The outcomes from the meeting were the development of top research priorities and a research agenda for exercise in SOT, which included the need for larger scale, multi-center intervention studies, development of standardized outcomes for physical function and surrogate measures for clinical trials, examining novel modes of exercise delivery and novel outcomes from exercise training studies such as immunity, infection, cognition and economic outcomes. The development and dissemination of "expert consensus guidelines," synthesizing both the best available evidence and expert opinion was prioritized as a key step toward improving program delivery.


Asunto(s)
Consenso , Ejercicio Físico , Trasplante de Órganos , Composición Corporal , Humanos , Calidad de Vida
12.
J Dairy Sci ; 97(2): 1047-56, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24359813

RESUMEN

Improved representation of postabsorptive N metabolism in lactating dairy cows requires a better understanding of protein synthesis regulation in the mammary glands. This study aimed to determine the quantitative effects of Ile, Leu, Met, and Thr on the phosphorylation state of signaling proteins that regulate protein synthesis. The experiment used a composite design with a central point, 2 axial points per AA, and a complete 2(4) factorial. All of the other AA were provided at the concentrations in Dulbecco's modified Eagle's medium. The experiment was replicated with tissues from 5 lactating cows. Mammary tissue slices (0.12 ± 0.02 g) were incubated for 4h. Total and site-specific phosphorylated mammalian target of rapamycin (mTOR; Ser2448), eukaryotic elongation factor (eEF) 2 (Thr56), ribosomal protein S6 (Ser235/236), and eukaryotic initiation factor 2α (Ser51) were determined by western immunoblotting. Tissue concentrations of the 4 AA studied responded linearly to media supply. Addition of Ile, Leu, Met, or Thr had no effect on eukaryotic initiation factor 2α phosphorylation. Isoleucine and Thr positively affected mTOR phosphorylation. However, the 2 AA had an antagonistic relationship. Similarly, Ile linearly increased ribosomal protein S6 phosphorylation, and Thr inhibited the Ile effect. In addition, eEF2 phosphorylation was linearly decreased by Ile and Leu. Threonine curvilinearly decreased eEF2 phosphorylation, Ile and Leu negatively interacted on eEF2, and Thr tended to inhibit Leu effects on eEF2. This work demonstrated saturable responses and interactions between AA on activation of the mTOR pathway. Incorporation of these concepts into milk protein response models will help to improve milk and milk protein yield predictions and increase postabsorptive N efficiency and reduce N excretion by dairy cows.


Asunto(s)
Isoleucina/farmacología , Leucina/farmacología , Glándulas Mamarias Animales/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Treonina/farmacología , Animales , Bovinos , Células Epiteliales/metabolismo , Femenino , Lactancia/efectos de los fármacos , Lactancia/fisiología , Glándulas Mamarias Animales/metabolismo , Metionina/metabolismo , Leche/metabolismo , Proteínas de la Leche/metabolismo , Fosforilación , Biosíntesis de Proteínas , Proteínas/metabolismo , Proteína S6 Ribosómica/metabolismo , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Serina-Treonina Quinasas TOR/genética
13.
J Dairy Sci ; 97(5): 2998-3005, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24582441

RESUMEN

Specific AA affect rates of milk protein synthesis in the mammary glands of lactating cows. The objective of this study was to quantify the rate of αS1-casein synthesis in response to Ile, Leu, Met, and Thr supplementation, and to test the single-limiting AA theory for milk protein synthesis by exploring interactions among these AA. Effects of Ile, Leu, Met, and Thr were studied in vitro with a composite design containing a central point repeated 4 times, with 2 axial points per AA and a complete 2(4) factorial. Other AA were at the concentration in Dulbecco's modified Eagle medium/F12 medium (DMEM). The experiment was replicated with mammary tissue from 5 lactating cows. Mammary tissue slices (0.12 ± 0.02 g) were incubated for 4h at 37°C in 5 mL of treatment medium containing (2)H5-Phe. Caseins were precipitated from cell homogenate supernatants. Enrichment with (2)H5-Phe of the N[34]LLRFFVAPFPE αS1 peptide was determined by matrix-assisted laser desorption/ionization-tandem time-of-flight (MALDI-TOF-TOF), which was used to determine enrichment of Phe in the transfer (t)RNA pool and αS1-casein fractional synthesis rates (CFSR). Data were analyzed with a polynomial mixed model containing linear, quadratic, and 2-factor interactions for Ile, Leu, Met, and Thr, and cow and residual as random factors. Interactions were not significant at P<0.1 and were removed from the model. Increasing concentrations of Ile, Leu, Met, and Thr simultaneously increased CFSR curvilinearly with a predicted maximum response of 4.32 ± 0.84%/h at 63% of DMEM concentrations. The maximum response to each of the 4 AA was at 71, 49, 60, and 32% of the concentration in DMEM, for Ile, Leu, Met, and Thr, respectively. These values correspond to 270, 120, 440, and 140% the plasma concentrations of Ile, Leu, Met, and Thr observed in lactating cows fed to meet National Research Council requirements, respectively. The CFSR estimated at those maxima were similar among AA (3.6 ± 0.6%/h). Individual AA effects on CFSR did not correlate with mammalian target of rapamycin (mTOR) signaling. Independent responses of CFSR to individual essential AA observed in this study contradict the single-limiting AA theory assumed in current requirement systems. The saturable responses in CFSR to these 4 AA also highlight the inadequacy of using a fixed postabsorptive AA efficiency approach for determining AA requirements for milk protein synthesis.


Asunto(s)
Aminoácidos/metabolismo , Caseínas/biosíntesis , Bovinos , Leche/química , Aminoácidos/administración & dosificación , Aminoácidos Esenciales/metabolismo , Animales , Caseínas/química , Caseínas/genética , Femenino , Regulación de la Expresión Génica/fisiología , Lactancia/fisiología , Glándulas Mamarias Animales/metabolismo , Proteínas de la Leche/análisis , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo
14.
Am J Transplant ; 13(10): 2722-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24007361

RESUMEN

Primary graft failure and chronic lung allograft dysfunction (CLAD) limit lung transplant long-term outcomes. Various lung diseases have been correlated with surfactant protein (SP) expression and polymorphisms. We sought to investigate the role of SP expression in lung allografts prior to implantation, in relation to posttransplant outcomes. The expression of SP-(A, B, C, D) mRNA was assayed in 42 allografts. Posttransplant assessments include pulmonary function tests, bronchoscopy, broncho-alveolar lavage fluid (BALF) and biopsies to determine allograft rejection. BALF was assayed for SP-A, SP-D in addition to cytokines IL-8, IL-12 and IL-2. The diagnosis of CLAD was evaluated 6 months after transplantation. Lung allografts with low SP-A mRNA expression prior to implantation reduced survival (Log-rank p < 0.0001). No association was noted for the other SPs. Allografts with low SP-A mRNA had greater IL-2 (p = 0.03) and IL-12 (p < 0.0001) in the BALF and a greater incidence of rejection episodes (p = 0.003). Levels of SP-A mRNA expression were associated with the SP-A2 polymorphisms (p = 0.015). Specifically, genotype 1A1A(0) was associated with lower SP-A mRNA expression (p < 0.05). Lung allografts with low levels of SP-A mRNA expression are associated with reduced survival. Lung allograft SP-A mRNA expression appears to be associated with SP-A gene polymorphisms.


Asunto(s)
Rechazo de Injerto/genética , Enfermedades Pulmonares/cirugía , Trasplante de Pulmón , Polimorfismo Genético/genética , Proteína A Asociada a Surfactante Pulmonar/genética , Adulto , Anciano , Aloinjertos , Líquido del Lavado Bronquioalveolar , Citocinas/genética , Femenino , Estudios de Seguimiento , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Pronóstico , Estudios Prospectivos , Proteína D Asociada a Surfactante Pulmonar/genética , ARN Mensajero/genética , Estudios Retrospectivos , Tasa de Supervivencia
15.
Am J Transplant ; 12(7): 1929-35, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22486950

RESUMEN

Voriconazole is commonly used for prophylaxis and treatment of invasive aspergillosis in lung transplant recipients. However, the use of voriconazole may at times be limited by the development of hepatotoxicity. Our goal is to determine predictors of voriconazole-associated hepatotoxicity in lung transplant recipients. We conducted a single center retrospective cohort study of lung transplant recipients from 2006 to 2010 who received voriconazole therapy. We compared characteristics of patients who developed hepatotoxicity and those who did not. One hundred five lung transplant recipients received voriconazole. Hepatotoxicity occurred in 51% (54/105) of patients and lead to discontinuation in 34% (36/105). In univariate analysis, age less than 40 years, cystic fibrosis, use of azathioprine, history of liver disease and early initiation of voriconazole were associated with hepatotoxicity. In multivariable logistic regression analysis, perioperative initiation of voriconazole (within 30 days of transplantation) was independently associated with hepatotoxicity (OR 4.37, 95% CI: 1.53-12.43, p = 0.006). The five risk factors identified in the univariate analysis were used to build a K-nearest neighbor algorithm predictive model for hepatotoxicity. This model predicted hepatotoxicity with an accuracy of 70%. Voriconazole therapy initiated within the first 30 days of transplantation is associated with a greater risk of developing hepatotoxicity.


Asunto(s)
Antifúngicos/efectos adversos , Hígado/efectos de los fármacos , Trasplante de Pulmón , Pirimidinas/efectos adversos , Triazoles/efectos adversos , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Voriconazol , Adulto Joven
16.
Am J Transplant ; 12(10): 2608-22, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22958872

RESUMEN

An increasing number of patients older than 65 years are referred for and have access to organ transplantation, and an increasing number of older adults are donating organs. Although short-term outcomes are similar in older versus younger transplant recipients, older donor or recipient age is associated with inferior long-term outcomes. However, age is often a proxy for other factors that might predict poor outcomes more strongly and better identify patients at risk for adverse events. Approaches to transplantation in older adults vary across programs, but despite recent gains in access and the increased use of marginal organs, older patients remain less likely than other groups to receive a transplant, and those who do are highly selected. Moreover, few studies have addressed geriatric issues in transplant patient selection or management, or the implications on health span and disability when patients age to late life with a transplanted organ. This paper summarizes a recent trans-disciplinary workshop held by ASP, in collaboration with NHLBI, NIA, NIAID, NIDDK and AGS, to address issues related to kidney, liver, lung, or heart transplantation in older adults and to propose a research agenda in these areas.


Asunto(s)
Trasplante de Órganos , Anciano , Asignación de Recursos para la Atención de Salud , Humanos , Inmunosupresores/uso terapéutico , Selección de Paciente , Justicia Social , Donantes de Tejidos , Resultado del Tratamiento
17.
Clin Transplant ; 26(1): 34-41, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21272072

RESUMEN

People with severe cystic fibrosis (CF) lung disease with co-existent CF-associated liver disease (CFLD) are often excluded from consideration of sole lung transplantation, largely because of the concerns that they will subsequently develop hepatic decompensation. This retrospective cohort study aimed at determining whether patients with severe cirrhosis caused by CFLD have any differences in perioperative and relevant post-transplant outcomes compared to CF patients without CFLD when undergoing sole lung transplantation. Six patients with CFLD were matched with 18 CF patients without CFLD undergoing sole lung transplant at the same institution. There were no differences in total operative time or intra-operative requirements for cardiopulmonary bypass or blood products. Over a period of five yr post-transplant, no differences were observed between the two groups in body mass index, six-min walk, lung function, and survival. None of the CFLD subjects developed variceal bleeding; however, one developed hepatocellular and renal failure at four yr post-transplant and is being assessed for liver-kidney transplant. One additional patient with CFLD required repeat lung transplantation for bronchiolitis obliterans syndrome. This study provides evidence that CF patients with liver cirrhosis caused by CFLD can safely be considered for sole lung transplantation provided there is no evidence of significant hepatocellular dysfunction with decompensated cirrhosis or hepatic synthetic failure.


Asunto(s)
Fibrosis Quística/mortalidad , Fibrosis Quística/terapia , Cirrosis Hepática/mortalidad , Trasplante de Pulmón/mortalidad , Adolescente , Adulto , Niño , Fibrosis Quística/complicaciones , Femenino , Volumen Espiratorio Forzado , Humanos , Cirrosis Hepática/etiología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Adulto Joven
18.
J Magn Reson Imaging ; 33(5): 1229-34, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21509883

RESUMEN

PURPOSE: To present a novel technique for measuring tissue enhancement in breast fibroglandular tissue regions on contrast-enhanced breast magnetic resonance imaging (MRI) aimed at quantifying the enhancement of breast parenchyma, also known as "background enhancement." MATERIALS AND METHODS: Our quantitative method for measuring breast MRI background enhancement was evaluated in a population of 16 healthy volunteers. We also demonstrate the use of our new technique in the case study of one subject classified as high risk for developing breast cancer who underwent 3 months of tamoxifen therapy. RESULTS: We obtained quantitative measures of background enhancement in all cases. The high-risk patient exhibited a 37% mean reduction in background enhancement with treatment. CONCLUSION: Our quantitative method is a robust and promising tool that may allow investigators to quantify and document the potential adverse effect of background enhancement on diagnostic accuracy in larger populations.


Asunto(s)
Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Imagen por Resonancia Magnética/métodos , Adulto , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Persona de Mediana Edad , Receptores de Estrógenos/metabolismo , Reproducibilidad de los Resultados , Tamoxifeno/farmacología
19.
Aust Vet J ; 99(1-2): 11-14, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33025586

RESUMEN

CASE REPORT: This case report describes the clinical signs and case management of a 1-year-old neutered male Siberian Husky that accidentally ingested 635 mg/kg of oral acetazolamide (a carbonic anhydrase inhibitor). The dog presented with severe tachypnoea due to the development of hyperchloraemic metabolic acidosis and associated hypokalaemia that persisted for 7 days. Clinical and biochemical changes resolved with intravenous and subsequent oral supplementation of sodium bicarbonate and potassium. Complete recovery occurred within 9 days of presentation. CONCLUSION: To the authors' knowledge, this is the first case that reports overdosage of an oral carbonic anhydrase inhibitor in a dog and subsequent recovery with adequate supplementation and supportive care.


Asunto(s)
Acidosis , Enfermedades de los Perros , Acetazolamida/uso terapéutico , Acidosis/inducido químicamente , Acidosis/veterinaria , Animales , Inhibidores de Anhidrasa Carbónica , Enfermedades de los Perros/inducido químicamente , Enfermedades de los Perros/tratamiento farmacológico , Perros , Masculino , Potasio
20.
Transpl Infect Dis ; 12(6): 551-4, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20553438

RESUMEN

Cystic fibrosis (CF) lung transplant recipients infected with Burkholderia cenocepacia have a worse survival rate after lung transplantation than those who are not infected with this organism. The decreased survival is predominantly due to recurrent B. cenocepacia infection, with the majority of affected recipients succumbing within 3 months after transplant. B. cepacia complex (BCC) sepsis is one of the defining criteria for cepacia syndrome, an almost universally fatal necrotizing pneumonic illness. We report 2 CF patients who were long-term survivors of B. cenocepacia sepsis after lung transplantation. The aim of this report is to demonstrate that, although survival of B. cenocepacia sepsis after lung transplantation is extremely uncommon, with aggressive multidisciplinary management, long-term survival remains a realistic objective.


Asunto(s)
Infecciones por Burkholderia/mortalidad , Complejo Burkholderia cepacia/aislamiento & purificación , Fibrosis Quística/complicaciones , Fibrosis Quística/mortalidad , Trasplante de Pulmón/efectos adversos , Sepsis/mortalidad , Adulto , Antibacterianos/uso terapéutico , Infecciones por Burkholderia/microbiología , Infecciones por Burkholderia/cirugía , Complejo Burkholderia cepacia/clasificación , Complejo Burkholderia cepacia/efectos de los fármacos , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/cirugía , Empiema Pleural/microbiología , Empiema Pleural/cirugía , Femenino , Humanos , Pulmón/cirugía , Absceso Pulmonar/microbiología , Absceso Pulmonar/cirugía , Trasplante de Pulmón/mortalidad , Masculino , Sepsis/tratamiento farmacológico , Sepsis/microbiología , Sepsis/cirugía , Tasa de Supervivencia , Sobrevivientes , Adulto Joven
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