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1.
J Anim Breed Genet ; 138(3): 314-325, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33599015

RESUMEN

The Canadian Angus Association recently developed genetic evaluations for teat and udder structure, which impact efficiencies, and animal health and welfare. Genetic selection tools are most effective incorporated into economic selection indexes. An important factor in the development of economic indexes is the estimation of the economic value and discounted gene expression coefficients, and thereby the economic weight, of each trait. Traditional estimation methods, interrogation of previous studies quantifying the impact of the traits and bioeconomic modelling, were reinforced using producer surveys that employed pairwise ranking methods. Estimates of discounted genetic expression coefficients, economic value and economic weight for teat and udder score in Canadian Angus cattle were 0.31 per sire, $52.47, and $16.91 per score change on a per calf born basis, respectively, indicating that functional traits such as teat and udder structure have a significant impact on profitability and should be included in genetic selection programmes. Limitations in previous studies illustrate the need for longitudinal studies on traits that impact efficiencies and animal health and welfare.


Asunto(s)
Bovinos/genética , Animales , Peso Corporal , Canadá , Femenino , Lactancia , Glándulas Mamarias Animales , Fenotipo
2.
Pediatr Radiol ; 49(1): 141-145, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30159592

RESUMEN

Mediport (also known as port, portacath or Infusaport) is a commonly placed central venous access in pediatric patients. Fibrin sheath formation around the central venous catheter is a common biological response leading to port malfunction in the form of inability to aspirate but preserved capacity for infusion of fluids. If fibrinolytic therapy fails, percutaneous fibrin sheath stripping via transfemoral route or replacement with a new mediport are routine/conventional treatments for a fibrin sheath. We describe a novel technique for removing a fibrin sheath by exteriorizing the catheter through the neck entry site, stripping the fibrin sheath from the catheter manually under sterile conditions and replacing the catheter via a peel-away sheath introduced through the same skin incision as an alternative to complete port replacement or attempted catheter stripping.


Asunto(s)
Cateterismo Venoso Central , Catéteres de Permanencia , Fibrina , Adolescente , Niño , Falla de Equipo , Femenino , Humanos , Masculino , Estudios Retrospectivos , Terapia Trombolítica , Resultado del Tratamiento , Grado de Desobstrucción Vascular , Adulto Joven
3.
Genet Sel Evol ; 50(1): 48, 2018 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-30290764

RESUMEN

BACKGROUND: Heterosis has been suggested to be caused by dominance effects. We performed a joint genome-wide association analysis (GWAS) using data from multi-breed and crossbred beef cattle to identify single nucleotide polymorphisms (SNPs) with significant dominance effects associated with variation in growth and carcass traits and to understand the mode of action of these associations. METHODS: Illumina BovineSNP50 genotypes and phenotypes for 11 growth and carcass traits were available for 6796 multi-breed and crossbred beef cattle. After performing quality control, 42,610 SNPs and 6794 animals were used for further analyses. A single-SNP GWAS for the joint association of additive and dominance effects was conducted in purebred, crossbred, and combined datasets using the ASReml software. Genomic breed composition predicted from admixture analyses was included in the mixed effect model to account for possible population stratification and breed effects. A threshold of 10% genome-wide false discovery rate was applied to declare associations as significant. The significant SNPs with dominance association were mapped to their corresponding genes at 100 kb. RESULTS: Seven SNPs with significant dominance associations were detected for birth weight, weaning weight, pre-weaning daily gain, yearling weight and marbling score across the three datasets at a false discovery rate of 10%. These SNPs were located on bovine chromosomes 1, 3, 4, 6 and 21 and mapped to six putative candidate genes: U6atac, AGBL4, bta-mir-2888-1, REPIN1, ICA1 and NXPH1. These genes have interesting biological functions related to the regulation of gene expression, glucose and lipid metabolism and body fat mass. For most of the identified loci, we observed over-dominance association with the studied traits, such that the heterozygous individuals at any of these loci had greater genotypic values for the trait than either of the homozygous individuals. CONCLUSIONS: Our results revealed very few regions with significant dominance genetic effects across all the traits studied in the three datasets used. Regarding the SNPs that were detected with dominance associations, further investigation is needed to determine their relevance in crossbreeding programs assuming that dominance effects are the main cause of (or contribute usefully to) heterosis.


Asunto(s)
Bovinos/genética , Vigor Híbrido , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Animales , Genes Dominantes , Estudio de Asociación del Genoma Completo , Hibridación Genética , Selección Artificial
4.
J Hepatol ; 66(5): 987-1000, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28027971

RESUMEN

BACKGROUND & AIMS: Hepatocyte transplantation partially corrects genetic disorders and has been associated anecdotally with reversal of acute liver failure. Monitoring for graft function and rejection has been difficult, and has contributed to limited graft survival. Here we aimed to use preparative liver-directed radiation therapy, and continuous monitoring for possible rejection in an attempt to overcome these limitations. METHODS: Preparative hepatic irradiation was examined in non-human primates as a strategy to improve engraftment of donor hepatocytes, and was then applied in human subjects. T cell immune monitoring was also examined in human subjects to assess adequacy of immunosuppression. RESULTS: Porcine hepatocyte transplants engrafted and expanded to comprise up to 15% of irradiated segments in immunosuppressed monkeys preconditioned with 10Gy liver-directed irradiation. Two patients with urea cycle deficiencies had early graft loss following hepatocyte transplantation; retrospective immune monitoring suggested the need for additional immunosuppression. Preparative radiation, anti-lymphocyte induction, and frequent immune monitoring were instituted for hepatocyte transplantation in a 27year old female with classical phenylketonuria. Post-transplant liver biopsies demonstrated multiple small clusters of transplanted cells, multiple mitoses, and Ki67+ hepatocytes. Mean peripheral blood phenylalanine (PHE) level fell from pre-transplant levels of 1343±48µM (normal 30-119µM) to 854±25µM (treatment goal ≤360µM) after transplant (36% decrease; p<0.0001), despite transplantation of only half the target number of donor hepatocytes. PHE levels remained below 900µM during supervised follow-up, but graft loss occurred after follow-up became inconsistent. CONCLUSIONS: Radiation preconditioning and serial rejection risk assessment may produce better engraftment and long-term survival of transplanted hepatocytes. Hepatocyte xenografts engraft for a period of months in non-human primates and may provide effective therapy for patients with acute liver failure. LAY SUMMARY: Hepatocyte transplantation can potentially be used to treat genetic liver disorders but its application in clinical practice has been impeded by inefficient hepatocyte engraftment and the inability to monitor rejection of transplanted liver cells. In this study, we first show in non-human primates that pretreatment of the host liver with radiation improves the engraftment of transplanted liver cells. We then used this knowledge in a series of clinical hepatocyte transplants in patients with genetic liver disorders to show that radiation pretreatment and rejection risk monitoring are safe and, if optimized, could improve engraftment and long-term survival of transplanted hepatocytes in patients.


Asunto(s)
Rechazo de Injerto , Hepatocitos/trasplante , Hígado/efectos de la radiación , Acondicionamiento Pretrasplante , Adulto , Animales , Femenino , Humanos , Hepatopatías/terapia , Macaca fascicularis , Masculino , Porcinos , Trasplante Heterólogo
5.
Blood ; 126(22): 2475-8, 2015 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-26468228

RESUMEN

Blockade of immune checkpoints (ICPs) has led to impressive responses in cancer patients. However, the impact of preexisting immunity and ICPs on the risk of malignant transformation in human preneoplasia has not been prospectively studied. We prospectively analyzed antigen-specific B/T-cell immunity, immune composition of the tumor microenvironment, and the expression of a panel of ICPs on tumor and tumor-infiltrating immune cells in 305 patients with asymptomatic monoclonal gammopathy enrolled in S0120 under the auspices of SWOG. T-cell immunity against stem-cell antigen SOX2 and preserved humoral responses at study entry independently correlated with reduced risk of progression to clinical myeloma. Among the ICPs analyzed, expression of programmed death-ligand 1 (PD-L1) on tumor and infiltrating T cells correlated with increased risk of clinical malignancy, and blockade of this pathway boosted anti-SOX2 immunity in culture. These data suggest that stem-cell antigens and PD-L1 may be targeted for immunoprevention of myeloma. This trial was registered at www.clinicaltrials.gov as #NCT00900263.


Asunto(s)
Antígenos de Neoplasias/inmunología , Linfocitos B/inmunología , Inmunidad Celular , Mieloma Múltiple/inmunología , Factores de Transcripción SOXB1/inmunología , Células Madre/inmunología , Linfocitos T/inmunología , Linfocitos B/patología , Antígeno B7-H1/inmunología , Femenino , Humanos , Masculino , Mieloma Múltiple/patología , Mieloma Múltiple/prevención & control , Estudios Prospectivos , Células Madre/patología , Linfocitos T/patología
7.
Respir Res ; 16: 35, 2015 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-25889509

RESUMEN

BACKGROUND: The intake of nutrients with antioxidant properties is hypothesized to augment antioxidant defenses, decrease oxidant damage to tissues, and attenuate age-related rate of decline in lung function. The objective was to determine whether long-term intervention with selenium and/or vitamin E supplements attenuates the annual rate of decline in lung function, particularly in cigarette smokers. METHODS: The Respiratory Ancillary Study (RAS) tested the single and joint effects of selenium (200 µg/d L-selenomethionine) and vitamin E (400 IU/day all rac-α-tocopheryl acetate) in a randomized double-blind placebo-controlled trial. At the end of the intervention, 1,641 men had repeated pulmonary function tests separated by an average of 3 years. Linear mixed-effects regression models estimated the effect of intervention on annual rate of decline in lung function. RESULTS: Compared to placebo, intervention had no main effect on either forced expiratory volume in the first second (FEV1) or forced expiratory flow (FEF25-75). There was no evidence for a smoking by treatment interaction for FEV1, but selenium attenuated rate of decline in FEF25-75 in current smokers (P = 0.0219). For current smokers randomized to selenium, annual rate of decline in FEF25-75 was similar to the annual decline experienced by never smokers randomized to placebo, with consistent effects for selenium alone and combined with vitamin E. CONCLUSIONS: Among all men, there was no effect of selenium and/or vitamin E supplementation on rate of lung function decline. However, current smokers randomized to selenium had an attenuated rate of decline in FEF25-75, a marker of airflow. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT00241865 .


Asunto(s)
Pulmón/efectos de los fármacos , Pulmón/fisiología , Selenio/administración & dosificación , Fumar/tratamiento farmacológico , Vitamina E/administración & dosificación , Anciano , Antioxidantes/administración & dosificación , Suplementos Dietéticos , Método Doble Ciego , Quimioterapia Combinada , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Función Respiratoria/tendencias , Fumar/metabolismo
8.
Pediatr Radiol ; 45(3): 430-4, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25145452

RESUMEN

BACKGROUND: Small-caliber plastic stents are sometimes placed across the hepaticojejunostomy in liver transplant recipients at the time of biliary reconstruction. These stents usually pass spontaneously, but they can be retained and, rarely, this may cause biliary obstruction. OBJECTIVE: The purpose of this paper is twofold: to describe the appearance of biliary tract obstruction caused by retained surgical stents in pediatric liver transplants, and to report how these stents can be removed using interventional radiology techniques. MATERIALS AND METHODS: Three pediatric patients presenting with biochemical and imaging evidence of biliary obstruction were encountered over a 6-month period. At percutaneous cholangiography all patients were found to have retained surgical stents which appeared to be causing biliary tract obstruction. Percutaneous snaring of the stents was undertaken. RESULTS: All stents were successfully removed using interventional radiology techniques, and follow-up showed no evidence of recurrent obstruction. CONCLUSION: Surgical stents in children undergoing hepaticojejunostomy may be retained and cause biliary obstruction. Radiologists involved with imaging these patients should be aware of this potential cause of biliary obstruction. This complication is amenable to interventional radiology techniques with good long-term results. There is no easy endoscopic or surgical treatment option in these patients.


Asunto(s)
Colangiografía , Colestasis/diagnóstico por imagen , Trasplante de Hígado , Complicaciones Posoperatorias/diagnóstico por imagen , Radiografía Intervencional , Stents/efectos adversos , Adulto , Preescolar , Colestasis/etiología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Adulto Joven
9.
Cancer ; 120(16): 2448-56, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24797726

RESUMEN

BACKGROUND: Insulin-like growth factor-1 receptor (IGF-1R) is implicated in the pathogenesis of rhabdomyosarcoma (RMS), osteosarcoma (OS), and synovial sarcoma (SS). The authors conducted a multi-institutional phase 2 trial of the monoclonal antibody R1507 in patients with various subtypes of recurrent or refractory sarcomas. METHODS: Eligibility criteria included age ≥ 2 years and a diagnosis of recurrent or refractory RMS, OS, SS, and other soft tissue sarcomas. Patients received a weekly dose of 9 mg/kg R1507 intravenously. The primary endpoint was the best objective response rate using World Health Organization criteria. Tumor imaging was performed every 6 weeks × 4 and every 12 weeks thereafter. RESULTS: From December 2007 through August 2009, 163 eligible patients from 33 institutions were enrolled. The median patient age was 31 years (range, 7-85 years). Histologic diagnoses included OS (n = 38), RMS (n = 36), SS (n = 23), and other sarcomas (n = 66). The overall objective response rate was 2.5% (95% confidence interval, 0.7%-6.2%). Partial responses were observed in 4 patients, including 2 patients with OS, 1 patient with RMS, and 1 patient with alveolar soft part sarcoma. Four additional patients (3 with RMS and 1 with myxoid liposarcoma) had a ≥ 50% decrease in tumor size that lasted for <4 weeks. The median progression-free survival was 5.7 weeks, and the median overall survival was 11 months. The most common grade 3/4 toxicities were metabolic (12%), hematologic (6%), gastrointestinal (4%), and general constitutional symptoms (8%). CONCLUSIONS: R1507 is safe and well tolerated but has limited activity in patients with recurrent or refractory bone and soft tissue sarcomas. Additional studies to help identify the predictive factors associated with clinical benefit in selected histologies such as RMS appear to be warranted.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Receptor IGF Tipo 1/inmunología , Sarcoma de Ewing/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales Humanizados , Neoplasias Óseas/inmunología , Neoplasias Óseas/patología , Niño , Supervivencia sin Enfermedad , Humanos , Persona de Mediana Edad , Sarcoma de Ewing/inmunología , Sarcoma de Ewing/patología , Resultado del Tratamiento , Adulto Joven
10.
J Vasc Interv Radiol ; 25(3): 411-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24581464

RESUMEN

PURPOSE: To study selective use of antibiotic-impregnated catheters in children at increased risk of venous catheter-related infections (CRIs). MATERIALS AND METHODS: From December 2008 to June 2009, 428 peripherally inserted central catheters (PICCs) were placed by the interventional radiology service of a large metropolitan children's hospital. This retrospective study analyzed demographic and outcome data for the 125 patients in this group at high risk for venous CRI. Patients at high risk were those with active systemic infection, previous complicated central venous access, intensive care unit (ICU) admission, intestinal failure, transplantation, complex congenital heart disease, or renal failure. Patients (age, 7.6 y ± 7.0; 73 male and 52 female) received a conventional or antibiotic-impregnated PICC, with 17 receiving more than one catheter. RESULTS: Of the 146 of 428 qualifying patient encounters (34%), 53 patients received an antibiotic-impregnated PICC and 93 received a conventional PICC, representing 5,080 total catheter-days (CDs). The rates of CRIs per 1,000 CDs, including catheter exit site infections and catheter-related bloodstream infections, were 0.86 for antibiotic-impregnated PICCs and 5.5 for conventional PICCs (P = .036). A propensity-based model predicts 15-fold greater infection-free survival over the lifetime of the catheter in patients who receive an antibiotic-impregnated PICC (P < .001). Antibiotic-impregnated PICC recipients with active infection or ICU admission at the time of insertion had no catheter-associated infections, compared with 3.42 and 9.46 infections per 1,000 CDs, respectively, for patients who received conventional PICCs. Patients with intestinal failure had 1.49 and 10 infections per 1,000 CDs with antibiotic-impregnated versus conventional PICCs, respectively. CONCLUSIONS: Antibiotic-impregnated long-term PICCs significantly improve infection-free catheter survival in pediatric patients at high risk.


Asunto(s)
Antibacterianos/administración & dosificación , Infecciones Relacionadas con Catéteres/epidemiología , Infecciones Relacionadas con Catéteres/prevención & control , Catéteres Venosos Centrales/estadística & datos numéricos , Implantes de Medicamentos/uso terapéutico , Stents Liberadores de Fármacos/estadística & datos numéricos , Infecciones Relacionadas con Catéteres/diagnóstico por imagen , Niño , Supervivencia sin Enfermedad , Femenino , Humanos , Estudios Longitudinales , Masculino , Pennsylvania/epidemiología , Prevalencia , Radiografía Intervencional/estadística & datos numéricos , Factores de Riesgo , Resultado del Tratamiento
11.
AJR Am J Roentgenol ; 203(6): W697-705, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25415736

RESUMEN

OBJECTIVE: Although neurofibromas are rare, their initial clinical and imaging presentation can mimic those of vascular anomalies, particularly if the characteristic clinical features of neurofibromatosis are not present. The diagnostic challenges encountered in five cases of histologically proven neurofibromas, initially diagnosed as vascular anomalies, are reviewed and discussed. CONCLUSION: The clinical and imaging differences between neurofibromas and vascular anomalies are detailed with the histopathologic features to better understand why some neurofibromas are diagnosed as vascular anomalies.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neurofibroma/patología , Neoplasias del Sistema Nervioso Periférico/patología , Neoplasias de los Tejidos Blandos/patología , Malformaciones Vasculares/patología , Adolescente , Adulto , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Lactante
14.
Clin Trials ; 10(1): 131-42, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23064404

RESUMEN

BACKGROUND: The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was a randomized, double-blind, placebo-controlled prostate cancer prevention study funded by the National Cancer Institute (NCI) and conducted by the Southwest Oncology Group (SWOG). A total of 35,533 men were assigned randomly to one of the four treatment groups (vitamin E + placebo, selenium + placebo, vitamin E + selenium, and placebo + placebo). The independent Data and Safety Monitoring Committee (DSMC) recommended the discontinuation of study supplements because of the lack of efficacy for risk reduction and because futility analyses demonstrated no possibility of benefit of the supplements to the anticipated degree (25% reduction in prostate cancer incidence) with additional follow-up. Study leadership agreed that the randomized trial should be terminated but believed that the cohort should be maintained and followed as the additional follow-up would contribute important information to the understanding of the biologic consequences of the intervention. Since the participants no longer needed to be seen in person to assess acute toxicities or to be given study supplements, it was determined that the most efficient and cost-effective way to follow them was via a central coordinated effort. PURPOSE: A number of changes were necessary at the local Study Sites and SELECT Statistical Center to transition to following participants via a Central Coordinating Center. We describe the transition process from a randomized clinical trial to the observational Centralized Follow-Up (CFU) study. METHODS: The process of transitioning SELECT, implemented at more than 400 Study Sites across the United States, Canada, and Puerto Rico, entailed many critical decisions and actions including updates to online documents such as the SELECT Workbench and Study Manual, a protocol amendment, reorganization of the Statistical Center, creation of a Transition Committee, development of materials for SELECT Study Sites, development of procedures to close Study Sites, and revision of data collection procedures and the process by which to contact participants. RESULTS: At the time of the publication of the primary SELECT results in December 2008, there were 32,569 men alive and currently active in the trial. As of 31 December 2011, 17,761 participants had been registered to the CFU study. This number is less than had been anticipated due to unforeseen difficulties with local Study Site institutional review boards (IRBs). However, from this cohort, we estimate that an additional 580 prostate cancer cases and 215 Gleason 7 or higher grade cancers will be identified. Over 109,000 individual items have been mailed to participants. Active SELECT ancillary studies have continued. The substantial SELECT biorepository is available to researchers; requests to use the specimens are reviewed for feasibility and scientific merit. As of April 2012, 12 proposals had been approved. LIMITATIONS: The accrual goal of the follow-up study was not met, limiting our power to address the study objectives satisfactorily. The CFU study is also dependent on a number of factors including continued funding, continued interest of investigators in the biorepository, and the continued contribution of the participants. Our experience may be less pertinent to investigators who wish to follow participants in a treatment trial or participants in prevention trials in other medical areas. CONCLUSIONS: Extended follow-up of participants in prevention research is important to study the long-term effects of the interventions, such as those used in SELECT. The approach taken by SELECT investigators was to continue to follow participants centrally via an annual questionnaire and with a web-based option. The participants enrolled in the CFU study represent a large, well-characterized, generally healthy cohort. The CFU has enabled us to collect additional prostate and other cancer endpoints and longer follow-up on the almost 18,000 participants enrolled. The utility of the extensive biorepository that was developed during the course of the SELECT is enhanced by longer follow-up.


Asunto(s)
Estudios de Cohortes , Recolección de Datos , Suplementos Dietéticos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Neoplasias de la Próstata/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Adulto , Anciano , Anciano de 80 o más Años , Canadá/epidemiología , Comités de Monitoreo de Datos de Ensayos Clínicos , Determinación de Punto Final , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , National Cancer Institute (U.S.) , Placebos/administración & dosificación , Neoplasias de la Próstata/epidemiología , Puerto Rico/epidemiología , Proyectos de Investigación , Selenio/administración & dosificación , Estados Unidos/epidemiología , Vitamina E/administración & dosificación
15.
JAMA ; 309(6): 578-86, 2013 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-23403682

RESUMEN

IMPORTANCE: The long-term effectiveness of Helicobacter pylori eradication programs for preventing gastric cancer will depend on recurrence risk and individual and community factors. OBJECTIVE: To estimate risk of H. pylori recurrence and assess factors associated with successful eradication 1 year after treatment. DESIGN, SETTING, AND PARTICIPANTS: Cohort analysis of 1463 randomized trial participants aged 21 to 65 years from 7 Latin American communities, who were treated for H. pylori and observed between September 2009 and July 2011. INTERVENTIONS: Randomization to 1 of 3 treatment groups: 14-day lansoprazole, amoxicillin, and clarithromycin (triple therapy); 5-day lansoprazole and amoxicillin followed by 5-day lansoprazole, clarithromycin, and metronidazole (sequential); or 5-day lansoprazole, amoxicillin, clarithromycin, and metronidazole (concomitant). Participants with a positive (13)C-urea breath test (UBT) 6 to 8 weeks posttreatment were offered voluntary re-treatment with 14-day bismuth-based quadruple therapy. MEASUREMENTS: Recurrent infection after a negative posttreatment UBT and factors associated with successful eradication at 1-year follow-up. RESULTS: Among participants with UBT-negative results who had a 1-year follow-up UBT (n=1091), 125 tested UBT positive, a recurrence risk of 11.5% (95% CI, 9.6%-13.5%). Recurrence was significantly associated with study site (P = .03), nonadherence to initial therapy (adjusted odds ratio [AOR], 2.94; 95% CI, 1.31-6.13; P = .01), and children in the household (AOR, 1.17; 95% CI, 1.01-1.35 per child; P = .03). Of the 281 with positive posttreatment UBT results, 138 completed re-treatment, of whom 93 tested UBT negative at 1 year. Among the 1340 who had a 1-year UBT, 80.4% (95% CI, 76.4%-83.9%), 79.8% (95% CI, 75.8%-83.5%), and 77.8% (95% CI, 73.6%-81.6%) had UBT-negative results in the triple, sequential, and concomitant groups, respectively (P = .61), with 79.3% overall effectiveness (95% CI, 77.1%-81.5%). In a single-treatment course analysis that ignored the effects of re-treatment, the percentage of UBT-negative results at 1 year was 72.4% (95% CI, 69.9%-74.8%) and was significantly associated with study site (P < .001), adherence to initial therapy (AOR, 0.26; 95% CI, 0.15-0.42; P < .001), male sex (AOR, 1.63; 95% CI, 1.25-2.13; P < .001), and age (AOR, 1.14; 95% CI, 1.02-1.27 per decade; P = .02). One-year effectiveness among all 1463 enrolled participants, considering all missing UBT results as positive, was 72.7% (95% CI, 70.3%-74.9%). CONCLUSIONS AND RELEVANCE: One year after treatment for H. pylori infection, recurrence occurred in 11.5% of participants who had negative posttreatment UBT results. Recurrence determinants (ie, nonadherence and demographics) may be as important as specific antibiotic regimen in determining the long-term success of H. pylori eradication interventions. Study findings are relevant to the feasibility of programs for the primary prevention of gastric cancer in high-incidence regions of Latin America. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01061437.


Asunto(s)
Antiinfecciosos/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Neoplasias Gástricas/prevención & control , 2-Piridinilmetilsulfinilbencimidazoles/uso terapéutico , Adulto , Amoxicilina/uso terapéutico , Bismuto/uso terapéutico , Pruebas Respiratorias , Claritromicina/uso terapéutico , Esquema de Medicación , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/patología , Humanos , Lansoprazol , América Latina/epidemiología , Masculino , Cumplimiento de la Medicación , Metronidazol/uso terapéutico , Persona de Mediana Edad , Prevención Primaria , Recurrencia , Riesgo , Neoplasias Gástricas/microbiología , Adulto Joven
16.
Lancet ; 378(9790): 507-14, 2011 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-21777974

RESUMEN

BACKGROUND: Evidence from Europe, Asia, and North America suggests that standard three-drug regimens of a proton-pump inhibitor plus amoxicillin and clarithromycin are significantly less effective for eradication of Helicobacter pylori infection than are 5-day concomitant and 10-day sequential four-drug regimens that include a nitroimidazole. These four-drug regimens also entail fewer antibiotic doses than do three-drug regimens and thus could be suitable for eradication programmes in low-resource settings. Few studies in Latin America have been done, where the burden of H pylori-associated diseases is high. We therefore did a randomised trial in Latin America comparing the effectiveness of four-drug regimens given concomitantly or sequentially with that of a standard 14-day regimen of triple therapy. METHODS: Between September, 2009, and June, 2010, we did a randomised trial of empiric 14-day triple, 5-day concomitant, and 10-day sequential therapies for H pylori in seven Latin American sites: Chile, Colombia, Costa Rica, Honduras, Nicaragua, and Mexico (two sites). Participants aged 21-65 years who tested positive for H pylori by a urea breath test were randomly assigned by a central computer using a dynamic balancing procedure to: 14 days of lansoprazole, amoxicillin, and clarithromycin (standard therapy); 5 days of lansoprazole, amoxicillin, clarithromycin, and metronidazole (concomitant therapy); or 5 days of lansoprazole and amoxicillin followed by 5 days of lansoprazole, clarithromycin, and metronidazole (sequential therapy). Eradication was assessed by urea breath test 6-8 weeks after randomisation. The trial was not masked. Our primary outcome was probablity of H pylori eradication. Our analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, registration number NCT01061437. FINDINGS: 1463 participants aged 21-65 years were randomly allocated a treatment: 488 were treated with 14-day standard therapy, 489 with 5-day concomitant therapy, and 486 with 10-day sequential therapy. The probability of eradication with standard therapy was 82·2% (401 of 488), which was 8·6% higher (95% adjusted CI 2·6-14·5) than with concomitant therapy (73·6% [360 of 489]) and 5·6% higher (-0·04% to 11·6) than with sequential therapy (76·5% [372 of 486]). Neither four-drug regimen was significantly better than standard triple therapy in any of the seven sites. INTERPRETATION: Standard 14-day triple-drug therapy is preferable to 5-day concomitant or 10-day sequential four-drug regimens as empiric therapy for H pylori infection in diverse Latin American populations. FUNDING: Bill & Melinda Gates Foundation, US National Institutes of Health.


Asunto(s)
2-Piridinilmetilsulfinilbencimidazoles/administración & dosificación , Amoxicilina/administración & dosificación , Antibacterianos/administración & dosificación , Claritromicina/administración & dosificación , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Metronidazol/administración & dosificación , Inhibidores de la Bomba de Protones/administración & dosificación , Adulto , Anciano , Pruebas Respiratorias , Esquema de Medicación , Quimioterapia Combinada , Femenino , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori/efectos de los fármacos , Humanos , Lansoprazol , América Latina , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento , Urea/metabolismo
17.
J Anim Sci ; 100(12)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36268991

RESUMEN

Rumen methanogenesis results in the loss of 6% to 10% of gross energy intake in cattle and globally is the single most significant source of anthropogenic methane (CH4) emissions. The purpose of this study was to analyze greenhouse gas traits recorded in a commercial feedlot unit to gain an understanding into the relationships between greenhouse gas traits and production traits. Methane and carbon dioxide (CO2) data recorded via multiple GreenFeed Emission Monitoring (GEM), systems as well as feed intake, live weight, ultrasound scanning data, and slaughter data were available on 1,099 animals destined for beef production, of which 648 were steers, 361 were heifers, and 90 were bulls. Phenotypic relationships between GEM emission measurements with feed intake, weight traits, muscle ultrasound data, and carcass traits were estimated. Utilization of GEM systems, daily patterns of methane output, and repeatability of GEM system measurements across averaging periods were also assessed. Methane concentrations varied with visit number, duration, and time of day of visit to the GEM system. Mean CH4 and CO2 varied between sex, with mean CH4 of 256.1 g/day ± 64.23 for steers, 234.7 g/day ± 59.46 for heifers, and 156.9 g/day ± 55.98 for young bulls. A 10-d average period of GEM system measurements were required for steers and heifers to achieve a minimum repeatability of 0.60; however, higher levels of repeatability were observed in animals that attended the GEM system more frequently. In contrast, CO2 emissions reached repeatability estimates >0.6 for steers and heifers in all averaging periods greater than 2-d, suggesting that cattle have a moderately consistent CO2 emission pattern across time periods. Animals with heavier bodyweights were observed to have higher levels of CH4 (correlation = 0.30) and CO2 production (correlation = 0.61), and when assessing direct methane, higher levels of dry matter intake were associated with higher methane output (correlation = 0.31). Results suggest that reducing CH4 can have a negative impact on growth and body composition of cattle. Methane ratio traits, such as methane yield and intensity were also evaluated, and while easy to understand and compare across populations, ratio traits are undesirable in animal breeding, due to the unpredictable level of response. Methane adjusted for dry matter intake and liveweight (Residual CH4) should be considered as an alternative emission trait when selecting for reduced emissions within breeding goals.


Methane production from cattle digestion results in the loss of 6% to 10% of gross energy intake in cattle and globally is the single most significant source of anthropogenic methane (CH4) emissions. The purpose of this study was to analyze greenhouse gas traits recorded in a commercial feedlot unit to gain an understanding into the relationships between greenhouse gas traits and production traits of economic importance. Methane and carbon dioxide emissions recorded using Greenfeed systems were available on a total of 1,099 animals. In addition, performance indicators such as feed intake, live weight, ultrasound scanning data, and slaughter data were also available on all animals. Phenotypic repeatability of CH4 ranged from 0.13 to 0.74, with a CH4 repeatability of >0.6 achieved by both heifers and steers in 10-d measuring period. Due to the high repeatability of CH4 measures, an accurate portrayal of CH4 production can be observed from a 10-d measuring period when measures are averaged. Methane emission data were positively correlated with traits of economic importance. Phenotypically, animals with heavier body weights and greater feed intake had higher emissions.


Asunto(s)
Gases de Efecto Invernadero , Metano , Bovinos/genética , Animales , Femenino , Masculino , Dieta/veterinaria , Ingestión de Alimentos , Rumen , Alimentación Animal/análisis
18.
Front Med (Lausanne) ; 9: 964448, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36250086

RESUMEN

Acute hepatic failure is associated with high morbidity and mortality for which the only definitive therapy is liver transplantation. Some fraction of those who undergo emergency transplantation have been shown to recover native liver function when transplanted with an auxiliary hepatic graft that leaves part of the native liver intact. Thus, transplantation could have been averted with the development and use of some form of hepatic support. The costs of developing and testing liver support systems could be dramatically reduced by the availability of a reliable large animal model of hepatic failure with a large therapeutic window that allows the assessment of efficacy and timing of intervention. Non-lethal forms of hepatic injury were examined in combination with liver-directed radiation in non-human primates (NHPs) to develop a model of acute hepatic failure that mimics the human condition. Porcine hepatocyte transplantation was then tested as a potential therapy for acute hepatic failure. After liver-directed radiation therapy, delivery of a non-lethal hepatic ischemia-reperfusion injury reliably and rapidly generated liver failure providing conditions that can enable pre-clinical testing of liver support or replacement therapies. Unfortunately, in preliminary studies, low hepatocyte engraftment and over-immune suppression interfered with the ability to assess the efficacy of transplanted porcine hepatocytes in the model. A model of acute liver failure in NHPs was created that recapitulates the pathophysiology and pathology of the clinical condition, does so with reasonably predictable kinetics, and results in 100% mortality. The model allowed preliminary testing of xenogeneic hepatocyte transplantation as a potential therapy.

19.
J Pediatr Surg ; 57(6): 1013-1017, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35307194

RESUMEN

BACKGROUND: Pulmonary nodules that are deep within lung parenchyma and/or small in size can be challenging to localize for biopsy. This study describes current trends in performance of image-guided localization techniques for pulmonary nodules in pediatric patients. METHODS: A retrospective review was performed on patients < 21 years of age undergoing localization of pulmonary nodules at 15 institutions. Localization and resection success, time in interventional radiology (IR), operating room (OR) and total anesthesia time, complications, and technical problems were compared between techniques. RESULTS: 225 patients were included with an average of 1.3 lesions (range 1-5). Median nodule size and depth were 4 mm (range 0-30) and 5.4 mm (0-61), respectively. The most common localization techniques were: wire + methylene blue dye (MBD) (28%), MBD only (25%), wire only (14%), technetium-99 only (11%), coil + MBD (7%) and coil only (5%). Localization technique was associated with institution (p < 0.01); technique and institution were significantly associated with mean IR, OR, and anesthesia time (all p < 0.05). Comparing techniques, there was no difference in successful IR localization (range 92-100%, p = 0.75), successful resection (94-100%, p = 0.98), IR technical problems (p = 0.22), or operative complications (p = 0.16). CONCLUSIONS: Many IR localization techniques for small pulmonary nodules in children can be successful, but there is wide variability in application by institution and in procedure time. LEVEL OF EVIDENCE: Retrospective review, Level 3.


Asunto(s)
Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Nódulo Pulmonar Solitario , Oncología Quirúrgica , Niño , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Azul de Metileno , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Nódulos Pulmonares Múltiples/cirugía , Estudios Retrospectivos , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/cirugía , Cirugía Torácica Asistida por Video/métodos , Tomografía Computarizada por Rayos X/métodos
20.
JAMA ; 306(14): 1549-56, 2011 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-21990298

RESUMEN

CONTEXT: The initial report of the Selenium and Vitamin E Cancer Prevention Trial (SELECT) found no reduction in risk of prostate cancer with either selenium or vitamin E supplements but a statistically nonsignificant increase in prostate cancer risk with vitamin E. Longer follow-up and more prostate cancer events provide further insight into the relationship of vitamin E and prostate cancer. OBJECTIVE: To determine the long-term effect of vitamin E and selenium on risk of prostate cancer in relatively healthy men. DESIGN, SETTING, AND PARTICIPANTS: A total of 35,533 men from 427 study sites in the United States, Canada, and Puerto Rico were randomized between August 22, 2001, and June 24, 2004. Eligibility criteria included a prostate-specific antigen (PSA) of 4.0 ng/mL or less, a digital rectal examination not suspicious for prostate cancer, and age 50 years or older for black men and 55 years or older for all others. The primary analysis included 34,887 men who were randomly assigned to 1 of 4 treatment groups: 8752 to receive selenium; 8737, vitamin E; 8702, both agents, and 8696, placebo. Analysis reflect the final data collected by the study sites on their participants through July 5, 2011. INTERVENTIONS: Oral selenium (200 µg/d from L-selenomethionine) with matched vitamin E placebo, vitamin E (400 IU/d of all rac-α-tocopheryl acetate) with matched selenium placebo, both agents, or both matched placebos for a planned follow-up of a minimum of 7 and maximum of 12 years. MAIN OUTCOME MEASURES: Prostate cancer incidence. RESULTS: This report includes 54,464 additional person-years of follow-up and 521 additional cases of prostate cancer since the primary report. Compared with the placebo (referent group) in which 529 men developed prostate cancer, 620 men in the vitamin E group developed prostate cancer (hazard ratio [HR], 1.17; 99% CI, 1.004-1.36, P = .008); as did 575 in the selenium group (HR, 1.09; 99% CI, 0.93-1.27; P = .18), and 555 in the selenium plus vitamin E group (HR, 1.05; 99% CI, 0.89-1.22, P = .46). Compared with placebo, the absolute increase in risk of prostate cancer per 1000 person-years was 1.6 for vitamin E, 0.8 for selenium, and 0.4 for the combination. CONCLUSION: Dietary supplementation with vitamin E significantly increased the risk of prostate cancer among healthy men. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT00006392.


Asunto(s)
Antioxidantes/efectos adversos , Suplementos Dietéticos/efectos adversos , Neoplasias de la Próstata/epidemiología , Selenio/administración & dosificación , Vitamina E/efectos adversos , Anciano , Antioxidantes/administración & dosificación , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/prevención & control , Riesgo , Vitamina E/administración & dosificación
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