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1.
Theor Popul Biol ; 149: 1-11, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36410496

RESUMEN

Large invasive species eradication programs are undertaken to protect native biodiversity and agriculture. Programs are typically followed by a series of surveys to assess the likelihood of eradication success and, when residual pests are detected, small-scale control or 'mop-ups' are implemented to eliminate these infestations. Further surveys follow to confirm absence with 'freedom' declared when a target probability of absence is reached. Such biosecurity programs comprise many interacting processes - stochastic biological processes including growth, and response and control interventions - and are an important component of post-border biosecurity. Statistical frameworks formulated to contribute to the design and efficiency of these surveillance and control programs are few and, those available, rely on the simulation of the component processes. In this paper we formulate an analytical Bayesian framework for a general biosecurity program with multiple components to assess pest-eradication success. Our model incorporates stochastic growth and detection processes, and several pest control mechanisms. Survey results and economic considerations are also taken into account to support a range of biosecurity management decisions. Using a case study we demonstrate that solutions match published simulation results and extend the available analysis. Principally, we show how analytical solutions can offer a powerful tool to support the design of effective and cost-efficient biosecurity systems, and we establish some general principles that guide and contribute to robust design.


Asunto(s)
Biodiversidad , Control de Plagas , Teorema de Bayes , Especies Introducidas , Probabilidad
2.
Theor Popul Biol ; 144: 70-80, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34762902

RESUMEN

It is not possible to establish the absence of a population with certainty using imperfect zero-sighting records, but absence can be inferred. In this paper we use Bayesian methods to formulate analytical inferred distributions and statistics. When such formulations are available, they offer a highly efficient and powerful means of analysis. Our purpose is to provide accessible and versatile formulations to support an assessment of population absence for management decisions, using data from a series of regular and targeted surveys with zero-sightings. The stochastic processes considered here are prior population size, growth and imperfect detection, which are combined into a single distribution with sufficient flexibility to accommodate alternative distributions for each of the driving processes. Analytical solutions formulated include the inferred mean and variance for population size or number of infested survey-units, the probability of absence, the probability of a series of negative surveys conditional on presence, and the probability a population is first detected in a given survey, although we also formulate other statistics and provide explicit thresholds designed to support management decisions. Our formulation and results are straightforward to apply and provide insight into the nonlinear interactions and general characteristics of such systems. Although motivated by an assessment of population absence following a pest eradication program, results are also relevant to the status of threatened species, to 'proof-of-freedom' requirements for trade, and for inferring population size when a population is first detected.


Asunto(s)
Especies en Peligro de Extinción , Extinción Biológica , Animales , Teorema de Bayes , Densidad de Población , Probabilidad
3.
Phys Rev E ; 104(1-2): 015304, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34412354

RESUMEN

Coarse-grained descriptions of microscopic systems often require a mesoscopic definition of momentum. The question arises as to the uniqueness of such a momentum definition at a particular coarse-graining scale. We show here that particularly the fluctuating properties of common definitions of momentum in coarse-grained methods like lattice gas and lattice Boltzmann do not agree with a fundamental definition of momentum. In the case of lattice gases, the definition of momentum will even disagree in the limit of large wavelength. For short times we derive analytical representations for the distribution of different momentum measures and thereby give a full account of these differences.

4.
Retina ; 41(10): 2009-2016, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34009185

RESUMEN

PURPOSE: To compare the visual outcomes after prompt pars plana vitrectomy (PPV) with tap biopsy and intravitreal antimicrobial injection to treat postinjection and postsurgery endophthalmitis. METHODS: The Cochrane Central Register of Controlled Trials, Ovid MEDLINE, and Ovid Embase databases were searched for articles published between January 2010 and November 2020. Two independent reviewers selected articles and extracted data. We analyzed data in RevMan 5.3 and assessed methodological quality using the Cochrane ROBINS-I tool. The mean improvement in visual outcome was compared between PPV and intravitreal antimicrobial injection as a relative risk of improving ≥2 lines and a mean logarithm of the minimal angle of resolution difference in improvement. RESULTS: Fifteen retrospective case series (1,355 eyes), of which 739 eyes (55%) received intravitreal antimicrobial injection and 616 (45%) received PPV as initial treatment, were included. The overall relative risk of improving 2 or more lines in PPV in comparison with intravitreal antimicrobial injection was 1.04 (95% CI 0.88-1.23; P = 0.61; I2 = 0%) with a mean difference of 0.04 (95% CI -0.18 to 0.27; P = 0.69; I2 = 0%). The results stayed robust when subgroup analysis based on causative procedure for endophthalmitis was performed. CONCLUSION: Intravitreal antimicrobial injection is noninferior to PPV for the treatment of postcataract operation, postinjection, and post-PPV endophthalmitis.


Asunto(s)
Antibacterianos/administración & dosificación , Biopsia , Endoftalmitis/terapia , Infecciones Bacterianas del Ojo/terapia , Complicaciones Posoperatorias , Vitrectomía/métodos , Endoftalmitis/tratamiento farmacológico , Endoftalmitis/microbiología , Endoftalmitis/cirugía , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Infecciones Bacterianas del Ojo/microbiología , Infecciones Bacterianas del Ojo/cirugía , Humanos , Inyecciones Intravítreas , Agudeza Visual/fisiología
5.
Phys Rev Lett ; 124(23): 234501, 2020 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-32603140

RESUMEN

Using the recently introduced molecular dynamics lattice gas approach, we test fluctuations of coarse-grained quantities. We show that as soon as the system can no longer be considered an ideal gas fluctuations fail to diminish upon coarse graining as is usually expected. These results suggest that current approaches to simulating fluctuating hydrodynamics may have to be augmented to achieve quantitative results for systems with a nonideal equation of state. The molecular dynamics lattice gas method gives a guidance to the exact nature of the fluctuation in such systems.

6.
Saudi J Gastroenterol ; 26(3): 113-119, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32436866

RESUMEN

BACKGROUND/AIM: Endoscopic ultrasound (EUS) and contrast-enhanced computed tomography (CT) with pancreas protocol are used in assessing the resectability of neoplastic pancreatic lesions. Here, we performed a diagnostic test accuracy (DTA) meta-analysis, comparing the diagnostic accuracy of EUS and CT in evaluating the resectability of pancreatic cancer using surgical assessment as the reference standard. PATIENTS AND METHODS: A comprehensive electronic search was conducted up to March 2020. Studies comparing EUS and CT in assessing the resectability of pancreatic cancer using surgical assessment as reference standard were included. QUADAS-2 tool was used to assess the quality of the included studies. After data extraction, an analysis was done using DerSimonian Laird method (random-effects model) to estimate the overall diagnostic odds ratio (DOR) and determine the best-fitting receiver operating characteristics (ROC) curve. RESULTS: Two studies, with 77 subjects combined, were included in the analysis. Overall, the risk of bias was moderate. EUS and CT were comparable in determining the resectability of pancreatic cancer with AUC = 75% (95% confidence interval (CI) 66%- 84%) for EUS as compared to 78% (95% CI 69%- 87%) for CT (P > 0.05). Pooled sensitivity and specificity was 87% (95% CI 70%- 96%) and 63% (95% CI 48%- 77%), respectively for EUS and 87% (95% CI 70%- 96%) and 70% (95% CI 55%- 83%), respectively for CT. DOR was 11.51 (95% CI 3.55- 36.81) for EUS as compared to 15.91 (95% CI 4.83- 51.62) for CT (P > 0.05). CONCLUSIONS: Both EUS and CT provide reasonable sensitivity and specificity to detect the resectability of pancreatic cancer.


Asunto(s)
Endosonografía , Neoplasias Pancreáticas , Tomografía Computarizada por Rayos X , Pruebas Diagnósticas de Rutina , Endosonografía/métodos , Humanos , Estadificación de Neoplasias , Páncreas , Neoplasias Pancreáticas/diagnóstico por imagen , Curva ROC , Sensibilidad y Especificidad
7.
Chem Phys Lipids ; 216: 65-72, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30219661

RESUMEN

In this study, we aimed to investigate the influence of liquid lipid types on different features of NLC. Four variations of liquid lipids such as coconut oil, fish oil, black seed oil and linseed oil were used, while for all variations, cetyl palmitate was used as the solid lipid. Different NLC were characterized and compared in terms of particle size, zeta potential, polydispersity index (PDI), drug entrapment percentage and drug loading capacity. The results indicated that NLC containing black seed oil has the smallest size. Other features like PDI, zeta potential and entrapment efficiency were the same for all the liquid lipids. By close margins, the NLC containing black seed oil had the highest percent of drug release and antioxidant activity compared to the rest. Diffusion was the major mechanism of the drug release according to the drug release kinetic fitted by Higuchi's model. Differential scanning calorimetry (DSC) and fourier transform infrared spectroscopy (FT-IR) confirmed no strong interaction between NLC constituents. The particles showed spherical shape morphology under atomic force microscopy (AFM). According to the cell viability assay on MCF-7 cell line, the curcumin loaded NLC composed of linseed oil showed better cytotoxic activity compared to the free curcumin.


Asunto(s)
Antioxidantes/química , Sistemas de Liberación de Medicamentos , Lípidos/química , Nanoestructuras/química , Antioxidantes/farmacología , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Humanos , Lípidos/farmacología , Células MCF-7 , Alcohol Feniletílico/análogos & derivados , Alcohol Feniletílico/antagonistas & inhibidores , Relación Estructura-Actividad
8.
Synth Biol (Oxf) ; 3(1)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30984875

RESUMEN

DNA origami, a method for constructing nanoscale objects, relies on a long single strand of DNA to act as the 'scaffold' to template assembly of numerous short DNA oligonucleotide 'staples'. The ability to generate custom scaffold sequences can greatly benefit DNA origami design processes. Custom scaffold sequences can provide better control of the overall size of the final object and better control of low-level structural details, such as locations of specific base pairs within an object. Filamentous bacteriophages and related phagemids can work well as sources of custom scaffold DNA. However, scaffolds derived from phages require inclusion of multi-kilobase DNA sequences in order to grow in host bacteria, and those sequences cannot be altered or removed. These fixed-sequence regions constrain the design possibilities of DNA origami. Here, we report the construction of a novel phagemid, pScaf, to produce scaffolds that have a custom sequence with a much smaller fixed region of 393 bases. We used pScaf to generate new scaffolds ranging in size from 1512 to 10 080 bases and demonstrated their use in various DNA origami shapes and assemblies. We anticipate our pScaf phagemid will enhance development of the DNA origami method and its future applications.

9.
Gut Microbes ; 8(1): 67-74, 2017 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-28080210

RESUMEN

Intestinal infections are a global challenge, connected to malnutrition and inadequate hygiene in developing countries, and to expanding antibiotic resistance in developed countries. In general, a healthy host is capable of fighting off gut pathogens or at least to recover from infections quickly. The underlying protective mechanism, termed colonization resistance, is provided by indigenous commensal communities (microbiota) that are shaped and aided by the host's epithelial and innate immune system. Commensal-pathogen interactions are governed by competition for a suitable niche for replication and stable colonization, nutrient availability, species-specific alterations of the metabolic environment, changes in oxygen tension and release of chemicals and proteinaceous toxins (bacteriocins). This protective intestinal milieu is further reinforced by antimicrobial factors and chemicals secreted by the epithelial barrier, by dendritic cell sensing and by homeostasis between T-cell subsets (Treg/Th17) in the lamina propria. The 3 players (host-microbiota-pathogen) communicate via direct interactions or secreted factors. Our recent manuscript illustrates that reactive oxygen species (ROS) are an integral part of colonization resistance and should be considered an interkingdom antivirulence strategy.


Asunto(s)
Microbioma Gastrointestinal , Peróxido de Hidrógeno/inmunología , Mucosa Intestinal/microbiología , Animales , Células Dendríticas/inmunología , Humanos , Mucosa Intestinal/inmunología , Subgrupos de Linfocitos T/inmunología
10.
Phys Rev E ; 96(1-1): 013314, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29347105

RESUMEN

We introduce a lattice gas implementation that is based on coarse-graining a molecular dynamics (MD) simulation. Such a lattice gas is similar to standard lattice gases, but its collision operator is informed by an underlying MD simulation. This can be considered an optimal lattice gas implementation because it allows for the representation of any system that can be simulated with MD. We show here that equilibrium behavior of the popular lattice Boltzmann algorithm is consistent with this optimal lattice gas. This comparison allows us to make a more accurate identification of the expressions for temperature and pressure in lattice Boltzmann simulations, which turn out to be related not only to the physical temperature and pressure but also to the lattice discretization. We show that for any spatial discretization, we need to choose a particular temporal discretization to recover the lattice Boltzmann equilibrium.

11.
Nucleic Acids Res ; 44(11): e102, 2016 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-27036861

RESUMEN

Scalable production of DNA nanostructures remains a substantial obstacle to realizing new applications of DNA nanotechnology. Typical DNA nanostructures comprise hundreds of DNA oligonucleotide strands, where each unique strand requires a separate synthesis step. New design methods that reduce the strand count for a given shape while maintaining overall size and complexity would be highly beneficial for efficiently producing DNA nanostructures. Here, we report a method for folding a custom template strand by binding individual staple sequences to multiple locations on the template. We built several nanostructures for well-controlled testing of various design rules, and demonstrate folding of a 6-kb template by as few as 10 unique strand sequences binding to 10 ± 2 locations on the template strand.


Asunto(s)
ADN/química , Nanoestructuras , Conformación de Ácido Nucleico , Secuencia de Bases , Nanotecnología , Oligonucleótidos/química
12.
13.
JSLS ; 18(3)2014.
Artículo en Inglés | MEDLINE | ID: mdl-25392631

RESUMEN

BACKGROUND/OBJECTIVES: It has been shown that major gynecologic laparoscopy is safe in hospital ambulatory settings, but there is little data to suggest the same in freestanding ambulatory surgery centers. This study evaluates the safety and efficacy of advanced gynecologic laparoscopic surgery using a fast-track model in freestanding ambulatory surgery centers and discusses our institution protocols. METHODS: Retrospective, multicenter review was conducted of major gynecologic surgeries from August 1st 2010 to September 30th 2011 in 3 surgical centers with one primary surgeon. All patients were treated for symptomatic uterine leiomyomas and/or endometriosis. Primary outcome measures were unplanned admissions and discharge within 23 hours. RESULTS: One hundred and thirty-four patients underwent major laparoscopic gynecologic surgery with a total of 160 procedures: 77 stage IV endometriosis treatment including 7 disk excisions of endometriosis from the large bowel, 3 ureteroneocystostomies and 1 partial bladder resection, 38 myomectomies, and 34 hysterectomies including 12 modified radical hysterectomies. The overall unplanned admission rate was 4.5%. One hundred and thirty-one patients (97.7%) were discharged within 24 hours after surgery. Three patients (2.2%) were transferred to the hospital postoperatively: 1 patient for observation of postoperative anemia and 2 patients for postoperative fever. Three patients (2.2%) were admitted to the hospital after discharge: 1 patient for postoperative ileus, 1 patient for postoperative fever, and 1 patient with septic pelvic thrombophlebitis. These postoperative issues all resolved without complication, and all patients had an uneventful follow-up. CONCLUSIONS: With appropriate resources and an experienced surgeon, advanced laparoscopic surgery can be safely performed in a fast-track ambulatory surgery center with a high rate of discharge within 23 hours and low unplanned readmission rate.


Asunto(s)
Instituciones de Atención Ambulatoria , Procedimientos Quirúrgicos Ambulatorios/métodos , Procedimientos Quirúrgicos Ginecológicos/métodos , Laparoscopía/métodos , Enfermedades Uterinas/cirugía , Adulto , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos
14.
Water Sci Technol ; 69(11): 2221-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24901615

RESUMEN

Ninety-nine pharmaceuticals and personal care products (PPCPs) were analyzed in influent, final effluent, and biosolids samples from a wastewater treatment plant employing a membrane bioreactor (MBR). High concentrations in influent were found for acetaminophen, caffeine, metformin, 2-hydroxy-ibuprofen, paraxanthine, ibuprofen, and naproxen (10(4)-10(5) ng/L). Final effluents contained clarithromycin, metformin, atenolol, carbamazepine, and trimethoprim (>500 ng/L) at the highest concentrations, while triclosan, ciprofloxacin, norfloxacin, triclocarban, metformin, caffeine, ofloxacin, and paraxanthine were found at high concentrations in biosolids (>10(3) ng/g dry weight). PPCP removals varied from -34% to >99% and 23 PPCPs had ≥90% removal. Of the studied PPCPs, 26 compounds have been rarely or never studied in previous membrane bioreactor (MBR) investigations. The removal pathway showed that acetaminophen, 2-hydroxy-ibuprofen, naproxen, ibuprofen, codeine, metformin, enalapril, atorvastatin, caffeine, paraxanthine, and cotinine exhibited high degradation/transformation. PPCPs showing strong sorption to solids included triclocarban, triclosan, miconazole, tetracycline, 4-epitetracycline, norfloxacin, ciprofloxacin, doxycycline, paroxetine, and ofloxacin. Trimethoprim, oxycodone, clarithromycin, thiabendazole, hydrochlorothiazide, erythromycin-H2O, carbamazepine, meprobamate, and propranolol were not removed during treatment, and clarithromycin was even formed during treatment. This investigation extended our understanding of the occurrence and fate of PPCPs in an MBR process through the analysis of the largest number of compounds in an MBR study to date.


Asunto(s)
Reactores Biológicos , Cosméticos/química , Preparaciones Farmacéuticas/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Membranas Artificiales , Tiempo
15.
Chem Commun (Camb) ; 49(88): 10379-81, 2013 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-24071916

RESUMEN

The low detection sensitivity of enzyme linked immunosorbent assays (ELISAs) is a central problem in science and limits progress in multiple areas of biology and medicine. In this report we demonstrate that the hydrocyanines, a family of fluorescent reactive oxygen species (ROS) probes, can act as turn on fluorescent horseradish peroxidase (HRP) probes and thereby increase the sensitivity of conventional ELISAs by two orders of magnitude.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Colorantes Fluorescentes/química , Peroxidasa de Rábano Silvestre/análisis , Límite de Detección , Carbocianinas/química , Línea Celular
17.
Anal Bioanal Chem ; 404(6-7): 2057-66, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22847478

RESUMEN

The lateral-flow (immuno)assay (LFA) has been widely investigated for the detection of molecular, macromolecular, and particle targets at the point-of-need due to its ease of use, rapid processing, and minimal power and laboratory equipment requirements. However, for some analytes, such as certain proteins, the detection limit of LFA is inferior to lab-based assays, such as the enzyme-linked immunosorbent assay, and needs to be improved. One solution for improving the detection limit of LFA is to concentrate the target protein in a solution prior to the detection step. In this study, a novel approach was used in the context of an aqueous two-phase micellar system comprised of the nonionic surfactant Triton X-114 to concentrate a model protein, namely transferrin, prior to LFA. Proteins have been shown to partition, or distribute, fairly evenly between the two phases of an aqueous two-phase system, which in turn results in their limited concentration in one of the two phases. Therefore, larger colloidal gold particles decorated with antibodies for transferrin were used in the concentration step to bind to transferrin and aid its partitioning into the top, micelle-poor phase. By manipulating the volume ratio of the two coexisting micellar phases and combining the concentration step with LFA, the transferrin detection limit of LFA was improved by tenfold from 0.5 to 0.05 µg/mL in a predictive manner. In addition to enhancing the sensitivity of LFA, this universal concentration method could also be used to improve other detection assays.


Asunto(s)
Fraccionamiento Químico/métodos , Inmunoensayo/métodos , Transferrina/análisis , Transferrina/aislamiento & purificación , Inmunoensayo/instrumentación , Límite de Detección , Micelas
18.
J Nat Med ; 66(3): 447-52, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22086673

RESUMEN

Alkanna species are used in Iranian traditional medicine for treatment of rheumatoid arthritis and other inflammatory diseases. This study was designed to evaluate the anti-inflammatory and anti-nociceptive effects of Alkanna frigida and Alkanna orientalis ethanolic extracts via the carrageenan-induced paw edema test and formalin test in rat and mouse, respectively. Ethanolic extracts of plant root were prepared and were injected intraperitoneally 60 min before carrageenan-induced inflammation or formalin-induced nociception at 100, 200 and 400 mg/kg. Anti-inflammatory effects of plants were monitored for 3 h after carrageenan injection and anti-nociceptive effects were evaluated during the first hour after formalin injection. Diclofenac, a well-known anti-inflammatory and anti-nociceptive agent, was used as a positive control. Our results show that, in contrast to Alkanna orientalis, ethanolic extract of Alkanna frigida significantly decreases carrageenan-induced inflammation at 400 mg/kg, especially 3 h after inflammation induction. Both Alkanna frigida and Alkanna orientalis ethanolic extracts possess a remarkable anti-nociceptive effect at each dose (100, 200 and 400 mg/kg) in a dose-dependent manner during the first hour after formalin injection.The present findings provide more evidence for the potential anti-nociceptive effect of Alkanna sp. and the anti-inflammatory effect of Alkanna frigida. It supports their traditional indication in the treatment of pain and inflammatory-related diseases. These useful effects may result from the inhibitory interaction of the plant ethanolic extract with cyclooxygenase-2 enzyme and the subsequent reduction in prostaglandin production.


Asunto(s)
Analgésicos/uso terapéutico , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Boraginaceae/química , Etanol/química , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Analgésicos/química , Animales , Carragenina/toxicidad , Femenino , Masculino , Ratones , Dolor/inducido químicamente , Dolor/tratamiento farmacológico , Ratas
19.
Ann Biomed Eng ; 39(4): 1235-51, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21350890

RESUMEN

Overexpressed receptors, characteristic of many cancers, have been targeted by various researchers to achieve a more specific treatment for cancer. A common approach is to use the natural ligand for the overexpressed receptor as a cancer-targeting agent which can deliver a chemically or genetically conjugated toxic molecule. However, it has been found that the therapeutic efficacy of such ligand-drug molecular conjugates can be limited, since they naturally follow the intracellular trafficking pathways of the endogenous ligands. Therefore, a thorough understanding of the intracellular trafficking properties of these ligands can lead to novel design criteria for engineering ligands to be more effective drug carriers. This review presents a few commonly used ligand/receptor systems where intracellular trafficking considerations can potentially improve the therapeutic efficacy of the ligand-drug molecular conjugates.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Portadores de Fármacos , Ligandos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Transporte Biológico Activo , Ingeniería Biomédica , Toxina Diftérica/administración & dosificación , Doxorrubicina/administración & dosificación , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Exotoxinas/administración & dosificación , Ácido Fólico/administración & dosificación , Transportadores de Ácido Fólico/metabolismo , Humanos , Interleucina-13/administración & dosificación , Modelos Biológicos , Receptores de Interleucina-13/metabolismo , Receptores de Transferrina/metabolismo , Ricina/administración & dosificación , Transducción de Señal , Transferrina/administración & dosificación , Transferrina/metabolismo , Factor de Crecimiento Transformador alfa/metabolismo
20.
Heart Surg Forum ; 10(2): E110-4, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17597032

RESUMEN

INTRODUCTION: Due to increasing need for and a shortage of donor organs, therapeutic procedures such as heart valve replacement for valve insufficiency and coronary artery bypass grafting (CABG) for graft vasculopathy (GVP) must be performed to improve allograft function to avoid retransplantation. METHODS: We performed a retrospective analysis of patients who underwent surgical procedures after orthotopic heart transplantation. Since 1989, we have performed more than 1400 heart transplantation procedures. Valve replacement was necessary in 8 patients and CABG was necessary in 3 patients. Five patients received valve prostheses (3 bioprostheses and 2 mechanical valves) at the tricuspid position. Three patients received a Hancock bioprosthesis at the mitral position. One of the 3 received the valve 3 years after heart transplantation while suffering from mitral regurgitation grade IV, and another patient received the valve 1 year following heart transplantation while suffering from mitral insufficiency grade III due to infective endocarditis. Three patients underwent coronary artery revascularization, 2 patients underwent the procedure 1 and 7 years after heart transplantation because of GVP, 1 patient underwent the procedure simultaneously with heart transplantation because of donor coronary artery disease. One patient received concomitant CABG with heart transplantation because of 75% left anterior descending stenoses in the donor organ, and one patient received CABG 1 year after heart transplantation because of rapidly progressive GVP in the left anterior descending artery. The third patient had 3-vessel disease with 95% left stem and 75% ramus circumflex, ramus marginalis, and ramus diagonalis. RESULTS: Two patients who underwent CABG and 4 patients who underwent valve replacement are still alive and maintain good clinical performance. One patient with a graft at the mitral position died 9 years after heart transplantation and 6 years after mitral valve replacement. Two patients with a graft at the tricuspid position died 17 and 4 years after heart transplantation (6 and 3 years after valve replacement, respectively). One patient with a bioprostheses at the tricuspid position had to be retransplanted 2 years following valve replacement while suffering from a paravalvular leakage grade III. CONCLUSION: Cardiac surgical procedures can be safely performed after heart transplantation. To improve graft and patient survival, such procedures must be carefully performed after heart transplantation to avoid retransplantation. The shortage of donor organs will and must lead to an increase in the number of conventional procedures performed to improve allograft function in transplanted hearts.


Asunto(s)
Puente de Arteria Coronaria/métodos , Estenosis Coronaria/cirugía , Trasplante de Corazón/efectos adversos , Enfermedades de las Válvulas Cardíacas/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Adulto , Anciano , Cardiomiopatía Dilatada/diagnóstico , Cardiomiopatía Dilatada/cirugía , Estenosis Coronaria/diagnóstico , Femenino , Estudios de Seguimiento , Rechazo de Injerto , Supervivencia de Injerto , Trasplante de Corazón/métodos , Enfermedades de las Válvulas Cardíacas/diagnóstico , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento , Grado de Desobstrucción Vascular/fisiología
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