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1.
J Surg Res ; 270: 555-563, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34826691

RESUMEN

BACKGROUND: All-terrain vehicle (ATV) use is widespread, however, little is known about injury patterns and outcomes in geriatric patients. We hypothesized that geriatric patients would have distinct and more severe injuries than non-geriatric adults after ATV trauma. METHODS: A retrospective cohort study was performed using the National Trauma Databank comparing non-geriatric (18-64) and geriatric adults (≥65) presenting after ATV trauma at Level 1 and 2 trauma centers from 2011 to 2015. Demographic, admission, and outcomes data were collected, including injury severity score (ISS), abbreviated injury scale (AIS) score, discharge disposition, and mortality. We performed univariate statistical tests between cohorts and multiple logistic regression models to assess for risk factors associated with severe injury (ISS>15) and mortality. RESULTS: 23,568 ATV trauma patients were identified, of whom 1,954 (8.3%) were geriatric. Geriatric patients had higher rates of severe injury(29.2 v 22.5%,p<0.0001), and thoracic (55.2 v 37.8%,p<0.0001) and spine (31.5 v 26.0%,p<0.0001) injuries, but lower rates of abdominal injuries (14.6 v 17.9%,p<0.001) as compared to non-geriatric adults. Geriatric patients had overall lower head injury rates (39.2 v 42.1%,p=0.01), but more severe head injuries (AIS>3) (36.2 vs 30.2%,p<0.001). Helmet use was significantly lower in geriatric patients (12.0 v 22.8%,p<0.0001). On multivariate analysis age increased the odds for both severe injury (OR 1.50, 95% CI 1.31-1.72, p<0.0001) and mortality (OR 5.07, 95% CI 3.42-7.50, p<0.0001). CONCLUSIONS: While severe injury and mortality after ATV trauma occurred in all adults, geriatric adults suffered distinct injury patterns and were at greater risk for severe injury and mortality.


Asunto(s)
Vehículos a Motor Todoterreno , Heridas y Lesiones , Adulto , Anciano , Dispositivos de Protección de la Cabeza , Humanos , Puntaje de Gravedad del Traumatismo , Estudios Retrospectivos , Centros Traumatológicos , Heridas y Lesiones/epidemiología , Heridas y Lesiones/etiología
2.
J Surg Res ; 262: 85-92, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33549849

RESUMEN

BACKGROUND: Snowmobiling is a popular activity that leads to geriatric trauma admissions; however, this unique trauma population is not well characterized. We aimed to compare the injury burden and outcomes for geriatric versus nongeriatric adults injured riding snowmobiles. MATERIALS AND METHODS: A retrospective cohort study was performed using the National Trauma Databank comparing nongeriatric (18-64) and geriatric adults (≥65) presenting after snowmobile-related trauma at level 1 and 2 trauma centers from 2011 to 2015. Demographic, admission, injury, and outcome data were collected and compared. A multivariate logistic regression model assessed for risk factors associated with severe injury (Injury Severity Score >15). Analysis was also performed using chi square, analysis of variance, and Kruskal-Wallis testing. RESULTS: A total of 2471 adult patients with snowmobile trauma were identified; 122 (4.9%) were geriatric. Rates of severe injury (Injury Severity Score >15) were similar between groups, 27.5% in geriatric patients and 22.5% in nongeriatric adults (P = 0.2). Geriatric patients experienced higher rates of lower extremity injury (50.4 versus 40.3%, P = 0.03), neck injury (4.1 versus 1.4%, P = 0.02), and severe spine injury (20.6 versus 7.0%, P = 0.004). Geriatric patients had longer hospitalizations (5 versus 3 d, P < 0.0001), rates of discharge to a facility (36.8% versus 12%, P < 0.0001), and higher mortality (4.1 versus 0.6%, P < 0.0001). Geriatric age did not independently increase the risk for severe injury. CONCLUSIONS: Geriatric age was not a significant predictor of severe injury after snowmobile trauma; however, geriatric patients suffered unique injuries, had longer hospitalizations, had higher rates of discharge to a facility, and had higher mortality. Tailored geriatric care may improve outcomes in this unique sport-related trauma population.


Asunto(s)
Vehículos a Motor Todoterreno , Heridas y Lesiones/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Traumatismos de la Pierna/epidemiología , Tiempo de Internación , Modelos Logísticos , Masculino , Persona de Mediana Edad , Traumatismos del Cuello/epidemiología , Estudios Retrospectivos , Heridas y Lesiones/mortalidad , Adulto Joven
3.
J Surg Res ; 259: 121-129, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33279837

RESUMEN

BACKGROUND: Downhill skiing accounts for a large portion of geriatric sport-related trauma. We assessed the national burden of geriatric versus nongeriatric ski trauma. MATERIALS AND METHODS: Adults presenting to level 1/2 trauma centers after ski-associated injuries from 2011 to 2015 were identified from the National Trauma Data Bank by ICD-9 code. We compared demographics, injury patterns, and outcomes between geriatric (age ≥65 y) and nongeriatric adult skiers (age 18-64 y). A multiple regression analysis assessed for risk factors associated with severe injury (Injury Severity Score >15). RESULTS: We identified 3255 adult ski trauma patients, and 16.7% (543) were geriatric. Mean ages for nongeriatric versus geriatric skiers were 40.8 and 72.1 y, respectively. Geriatric skiers more often suffered head (36.7 versus 24.3%, P < 0.0001), severe head (abbreviated injury scale score >3, 49.0 versus 31.5%, P < 0.0001) and thorax injuries (22.2 versus 18.1%, P = 0.03) as compared with nongeriatric skiers. Geriatric skiers were also more often admitted to the ICU (26.5 versus 14.9%, P < 0.0001), discharged to a facility (26.7 versus 11.6%, P < 0.0001), and suffered higher mortality rates (1.3 versus 0.4%, P = 0.004). Independent risk factors for severe injury included being male (OR: 1.68, CI: 1.22-2.31), helmeted (OR: 1.41, CI: 1.07-1.85), and having comorbidities (OR: 1.37, CI: 1.05-1.80). Geriatric age was not independently associated with severe injury. CONCLUSIONS: At level 1/2 trauma centers, geriatric age in ski trauma victims was associated with unique injury patterns, higher acuity, increased rates of facility care at discharge, and higher mortality as compared with nongeriatric skiers. Our findings indicate the need for specialized care after high impact geriatric ski trauma.


Asunto(s)
Costo de Enfermedad , Traumatismos Craneocerebrales/epidemiología , Esquí/lesiones , Traumatismos Torácicos/epidemiología , Centros Traumatológicos/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Anciano , Comorbilidad , Traumatismos Craneocerebrales/diagnóstico , Traumatismos Craneocerebrales/etiología , Traumatismos Craneocerebrales/prevención & control , Bases de Datos Factuales , Femenino , Dispositivos de Protección de la Cabeza/estadística & datos numéricos , Mortalidad Hospitalaria , Humanos , Puntaje de Gravedad del Traumatismo , Unidades de Cuidados Intensivos/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Admisión del Paciente/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo , Esquí/estadística & datos numéricos , Traumatismos Torácicos/diagnóstico , Traumatismos Torácicos/etiología , Estados Unidos/epidemiología , Adulto Joven
4.
Injury ; 51(9): 2040-2045, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32631617

RESUMEN

INTRODUCTION: As the population ages, trauma centers are seeing a significant volume of injured geriatric patients. However, there is limited data on geriatric off-roading incidents. We investigated the injury patterns, severity and outcomes of geriatric versus younger adult all-terrain vehicle (ATV) and snowmobile related trauma with the hypothesis that geriatric patients will have higher mortality and worsened outcomes. METHODS: The trauma registry at a New England Level 1 trauma center was queried by ICD 9/10 code for adult ATV and/or snowmobile-related trauma from 2011-2019. Data reviewed included demographic, admission, injury, and outcomes data including injury severity score (ISS), abbreviated injury scale (AIS) score, hospital disposition, and mortality. Patients were stratified by age into younger adults (18-64 years old) versus geriatric (65 years and older). Univariate analysis was performed to compare groups. RESULTS: Over the study period, we identified 390 adult ATV or snowmobile-related trauma patients, of whom 38 were geriatric. The mean ages for the younger adult vs. geriatric cohorts were 41(SD 13) and 73(SD 5), respectively. The majority of patients were male (77%). Compared to younger adults, geriatric patients were more often unhelmeted (66 v 38%, p=0.004) and more likely to present after ATV as opposed to snowmobile trauma (71 v 51%, p=0.028). Geriatric patients more often sustained both any chest trauma (68 v 41%, p=0.003) and severe chest trauma (AIS≥3, 55 v 31%, p=0.022), and more often required tube thoracostomy (26 v 12%, p=0.042). Geriatric patients were also more often discharged to a facility (39 v 14%, p<0.001) compared to younger patients. There were no differences between age cohorts regarding arrival Glasgow coma scale scores, ISS>15, length of stay, ventilator days, complications, or mortality. CONCLUSIONS: Following ATV or snowmobile-related trauma, geriatric patients were more likely to sustain severe chest trauma and to require additional care upon hospital discharge as compared to younger adults. Primary prevention should focus on encouraging helmet and chest protective clothing use in this geriatric population.


Asunto(s)
Vehículos a Motor Todoterreno , Heridas y Lesiones , Adolescente , Adulto , Anciano , Dispositivos de Protección de la Cabeza , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Centros Traumatológicos , Heridas y Lesiones/epidemiología , Heridas y Lesiones/terapia , Adulto Joven
5.
Mil Med ; 183(7-8): e257-e260, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29741715

RESUMEN

Introduction: Little is known regarding the confidence of military surgeons prior to combat zone deployment. Military surgeons are frequently deployed without peers experienced in combat surgery. We hypothesized that forward surgical team experience (FSTE) increases surgeon confidence with critical skill sets. Methods: We conducted a national survey of military affiliated personnel. We used a novel survey instrument that was piloted and validated by experienced military surgeons to collect demographics, education, practice patterns, and confidence parameters for trauma and surgical critical care skills. Skills were defined as crucial operative techniques for hemorrhage control and resuscitation. Surveyors were blinded to participants, and surveys were returned electronically via REDCap database. Data were analyzed with SPSS using appropriate models. Significance was considered p < 0.05. Results: Of 174 distributed surveys, 86 were completed. Nine individuals failed to characterize their FSTE, thus leaving a sample size of 77. At the time of first deployment, 78.4% were alone or with less experienced surgeons and 53.2% had less than 2 yr of post-residency practice. The respondents' confidence in damage control techniques and seven other trauma skills increased relative to FSTE. After adjusting for years of practice, number of trauma resuscitations performed per month and pre-deployment training, there remained a significant positive association between FSTE and confidence in damage control, thoracic surgery, extremity/junctional hemorrhage control, trauma systems administration, adult critical care and airway management. Conclusions: Training programs and years of general surgery practice do not replace FSTE among military surgeons. Pre-deployment training that mimics FST skill sets should be developed to improve military surgeon confidence and outcomes. Level of Evidence: Prognostic and Epidemiologic, Level IV.


Asunto(s)
Grupo de Atención al Paciente/normas , Autoeficacia , Procedimientos Quirúrgicos Operativos/psicología , Heridas y Lesiones/cirugía , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pennsylvania , Procedimientos Quirúrgicos Operativos/normas , Encuestas y Cuestionarios , Guerra/psicología
6.
Transplant Proc ; 47(10): 2944-51, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26707319

RESUMEN

INTRODUCTION: To address the shortage of donor hearts for transplantation, there is significant interest in liberalizing donor acceptance criteria. Therefore, the aim of this study was to evaluate cardiac donor characteristics from the United Network for Organ Sharing (UNOS) database to determine their impact on posttransplantation recipient outcomes. METHODS: Adult (≥18 years) patients undergoing heart transplantation from July 1, 2004, to December 31, 2012, in the UNOS Standard Transplant Analysis and Research (STAR) database were reviewed. Patients were stratified by 1-year posttransplantation status; survivors (group S, n = 13,643) and patients who died or underwent cardiac retransplantation at 1-year follow-up (group NS/R = 1785). Thirty-three specific donor variables were collected for each recipient, and independent donor predictors of recipient death or retransplantation at 1 year were determined using multivariable logistic regression analysis. RESULTS: Overall 1-year survival for the entire cohort was 88.4%. Mean donor age was 31.5 ± 11.9 years, and 72% were male. On multivariable logistic regression analysis, donor age >40 years (odds ratio [OR] 1.44, 95% confidence interval [CI] 1.27 to 1.64), graft ischemic time >3 hours (OR 1.32, 1.16 to 1.51), and the use of cardioplegia (OR 1.17, 1.01 to 1.35) or Celsior (OR 1.21, 1.06 to 1.38) preservative solution were significant predictors of recipient death or retransplantation at 1 year posttransplantation. Male donor sex (OR 0.83, 0.74 to 0.93) and the use of antihypertensive agents (OR 0.88, 0.77 to 1.00) or insulin (OR 0.84, 0.76 to 0.94) were protective from adverse outcomes at 1 year. CONCLUSIONS: These data suggest that donors who are older, female, or have a long projected ischemic time pose greater risk to heart transplant recipients in the short term. Additionally, certain components of donor management protocols, including antihypertensive and insulin administration, may be protective to recipients.


Asunto(s)
Supervivencia de Injerto , Trasplante de Corazón/mortalidad , Donantes de Tejidos/estadística & datos numéricos , Adulto , Factores de Edad , Antihipertensivos/uso terapéutico , Isquemia Fría/mortalidad , Bases de Datos Factuales , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Reoperación/estadística & datos numéricos , Factores de Riesgo , Factores Sexuales , Sobrevivientes/estadística & datos numéricos , Factores de Tiempo
7.
Am J Transplant ; 15(1): 55-63, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25534656

RESUMEN

Since the latest revision in US heart allocation policy (2006), the landscape and volume of transplant waitlists have changed considerably. Advances in mechanical circulatory support (MCS) prolong survival, but Status 1A mortality remains high. Several patient subgroups may be disadvantaged by current listing criteria and geographical disparity remains in waitlist time. This forum on US heart allocation policy was organized to discuss these issues and highlight concepts for consideration in the policy development process. A 25-question survey on heart allocation policy was conducted. Among attendees/respondents were 84 participants with clinical/published experience in heart transplant representing 51 US transplant centers, and OPTN/UNOS and SRTR representatives. The survey results and forum discussions demonstrated very strong interest in change to a further-tiered system, accounting for disadvantaged subgroups and lowering use of exceptions. However, a heart allocation score is not yet viable due to the long-term viability of variables (used in the score) in an ever-developing field. There is strong interest in more refined prioritization of patients with MCS complications, highly sensitized patients and those with severe arrhythmias or restrictive physiology. There is also strong interest in distribution by geographic boundaries modified according to population. Differences of opinion exist between small and large centers.


Asunto(s)
Política de Salud/tendencias , Insuficiencia Cardíaca/cirugía , Trasplante de Corazón/legislación & jurisprudencia , Asignación de Recursos/legislación & jurisprudencia , Obtención de Tejidos y Órganos/legislación & jurisprudencia , Humanos , Informe de Investigación , Estados Unidos
9.
Parkinsonism Relat Disord ; 18 Suppl 3: S6-9, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22867994

RESUMEN

UNLABELLED: Palliative care provides a holistic approach to symptom relief using a multidisciplinary team approach to enhance quality of life throughout the entire course of a particular illness. The care team consists of movement disorders neurologist, a palliative care physician, a wound care nurse, a spiritual counselor and a care coordinator. Palliative care concepts were applied to a group of advanced Parkinson disease (PD) patients in a dedicated Palliative Care Clinic. METHODS: A modified Edmonton Symptom Assessment System Scale for PD (ESAS-PD) was developed and applied to 65 PD patients at their initial consultation and following recommended interventions. Scores were compared to those of metastatic cancer patients reported in the palliative care literature. RESULTS: The ESAS-PD scores significantly improved after the interventions (56 and 40 respectively, p = 0.0001). The most improved items were constipation, dysphagia, anxiety, pain and drowsiness. ESAS-PD scores were not significantly different from metastatic cancer patients' ESAS scores. CONCLUSIONS: ESAS-PD is a quick, effective scale for assessment of late stage PD symptoms. Scores are sensitive to intervention, and therefore have potential clinical utility for physicians and other healthcare providers. Advanced PD patients have a similar degree of symptoms as metastatic cancer patients, respond to treatment in a similar way, and therefore should have access to palliative care services.


Asunto(s)
Instituciones de Atención Ambulatoria , Cuidados Paliativos/métodos , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/terapia , Grupo de Atención al Paciente , Índice de Severidad de la Enfermedad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/epidemiología
10.
Am J Transplant ; 12(9): 2487-97, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22776430

RESUMEN

This randomized, comparative, multinational phase 3b/4 study of patients 1-8 years postcardiac transplantation (mean 3.9 years) evaluated the effect of conversion from a calcineurin inhibitor (CNI) to sirolimus on renal function in patients with renal insufficiency. In total, 116 patients on CNI therapy with GFR 40-90 mL/min/1.73 m(2) were randomized (1:1) to sirolimus (n = 57) or CNI (n = 59). Intent-to-treat analysis showed the 1-year adjusted mean change from baseline in creatinine clearance (Cockcroft-Gault) was significantly higher with sirolimus versus CNI treatment (+3.0 vs. -1.4 mL/min/1.73 m(2) , respectively; p = 0.004). By on-therapy analysis, values were +4.7 and -2.1, respectively (p < 0.001). Acute rejection (AR) rates were numerically higher in the sirolimus group; 1 AR with hemodynamic compromise occurred in each group. A significantly higher treatment discontinuation rate due to adverse events (AEs; 33.3% vs. 0%; p < 0.001) occurred in the sirolimus group. Most common treatment-emergent AEs significantly higher in the sirolimus group were diarrhea (28.1%), rash (28.1%) and infection (47.4%). Conversion to sirolimus from CNI therapy improved renal function in cardiac transplant recipients with renal impairment, but was associated with an attendant AR risk and higher discontinuation rate attributable to AEs.


Asunto(s)
Trasplante de Corazón , Inmunosupresores/uso terapéutico , Riñón/fisiopatología , Sirolimus/uso terapéutico , Anciano , Femenino , Tasa de Filtración Glomerular , Humanos , Pruebas de Función Renal , Masculino , Persona de Mediana Edad
11.
Phys Rev Lett ; 107(14): 144801, 2011 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-22107200

RESUMEN

Measurements of the spatial and temporal coherence of single, femtosecond x-ray pulses generated by the first hard x-ray free-electron laser, the Linac Coherent Light Source, are presented. Single-shot measurements were performed at 780 eV x-ray photon energy using apertures containing double pinholes in "diffract-and-destroy" mode. We determined a coherence length of 17 µm in the vertical direction, which is approximately the size of the focused Linac Coherent Light Source beam in the same direction. The analysis of the diffraction patterns produced by the pinholes with the largest separation yields an estimate of the temporal coherence time of 0.55 fs. We find that the total degree of transverse coherence is 56% and that the x-ray pulses are adequately described by two transverse coherent modes in each direction. This leads us to the conclusion that 78% of the total power is contained in the dominant mode.

12.
J Trauma ; 69(1): 119-21, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20622586

RESUMEN

BACKGROUND: Computed tomography (CT) of the thoracic and lumbar (T/L) spine with reformats has become the imaging modality of choice for the identification of T/L spine fractures. The objective of this study was to directly compare chest/abdomen/pelvis CT (CAP CT) with CT with T/L reformats (T/L CT) for the identification of T/L spine fractures. METHODS: Patients who had both a CAP CT scan (5-mm imaging spacing) and T/L CT reconstruction (2.5-mm image spacing with sagittal and coronal reformats) were selected. A "fracture" group (N = 35) and a "no fracture" group (N = 57) were identified. The type and level of fracture were recorded. RESULTS: The CAP CT correctly identified all 35 patients with a thoracolumbar fracture (100% sensitivity; 95% confidence interval: 88-100%). A total of 80 separate fracture sites were present in the 35 patients. The CAP CT accurately identified 78 of those fractures (97.5% sensitivity; 95% confidence interval: 90.4-99.6%). The two fractures not identified on the CAP CT were both the transverse process fractures in patients with multiple fractures at different levels. CONCLUSION: Patients who have a CAP CT do not require reformats for clearance of the T/L spine.


Asunto(s)
Vértebras Lumbares/lesiones , Fracturas de la Columna Vertebral/diagnóstico por imagen , Vértebras Torácicas/lesiones , Tomografía Computarizada por Rayos X/métodos , Adulto , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Vértebras Torácicas/diagnóstico por imagen , Heridas no Penetrantes/diagnóstico por imagen
14.
J Biol Chem ; 283(16): 10822-34, 2008 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-18283105

RESUMEN

The focus of this work was to elucidate the mechanism for inhibition of neutrophil beta(2) integrin adhesion molecules by hyperoxia. Results demonstrate that exposure to high oxygen partial pressures increases synthesis of reactive species derived from type 2 nitric-oxide synthase and myeloperoxidase, leading to excessive S-nitrosylation of beta-actin and possibly profilin. Hyperoxia causes S-nitrosylation of the four cysteine moieties closest to the carboxyl-terminal end of actin, which results in formation of short actin filaments. This alters actin polymerization, network formation, and intracellular distribution, as well as inhibits beta(2) integrin clustering. If neutrophils are exposed to ultraviolet light to reverse S-nitrosylation, or are incubated with N-formyl-methionyl-leucine-phenylalanine to trigger "inside-out" activation, the effects of hyperoxia are reversed. We conclude that cytoskeletal changes triggered by hyperoxia inhibit beta(2) integrin-dependent neutrophil adhesion.


Asunto(s)
Actinas/fisiología , Antígenos CD18/metabolismo , Neutrófilos/metabolismo , Actinas/metabolismo , Secuencia de Aminoácidos , Animales , Antígenos CD18/biosíntesis , Adhesión Celular , Hiperoxia , Ratones , Ratones Noqueados , Datos de Secuencia Molecular , Oxígeno/metabolismo , Peroxidasa/metabolismo , Profilinas/metabolismo
15.
Am J Transplant ; 7(9): 2075-81, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17640316

RESUMEN

Retransplants comprise only a small minority (3-4%) of heart transplants, however outcome following retransplantation is compromised. Risk factors for a poor outcome following retransplantation include retransplantation early (<6 months) after primary transplant, retransplantation for acute rejection or early allograft failure, and retransplantation in an earlier era. The incidence of rejection and infection is similar following primary transplant and retransplantation. The compromised outcomes and risk factors for a poor outcome are similar in adult and pediatric heart retransplantation. However, due to the short half-life of the transplanted heart, it is an expectation that patients transplanted in childhood may require retransplantation. Based on the data available and the opinion of the working group, indications for heart retransplantation are (i) chronic severe cardiac allograft vasculopathy with symptoms of ischemia or heart failure (should be considered) or asymptomatic moderate or severe left ventricular dysfunction (may be considered) or (ii) chronic graft dysfunction with symptoms of progressive heart failure in the absence of active rejection. Patients with graft failure due to acute rejection with hemodynamic compromise, especially <6 months post-transplant, are inappropriate candidates for retransplantation. In addition, guidelines established for primary transplant candidacy should be strictly followed.


Asunto(s)
Rechazo de Injerto/cirugía , Trasplante de Corazón , Humanos , Pronóstico , Reoperación/métodos , Reoperación/estadística & datos numéricos
16.
Transpl Immunol ; 18(1): 13-21, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17584597

RESUMEN

The interleukin-2 receptor alpha chain (IL-2Ra, CD25) plays a major part in shaping the dynamics of T cell populations following immune activation, due to its role in T cell proliferation and survival. Strategies to blunt the effector responses in transplantation have been developed by devising pharmaceutical agents to block the IL-2 pathways. However, such strategies could adversely affect the CD25(+)FOXP3(+)T regulatory (T reg) populations which also rely on intereukin-2 signaling for survival. The present study shows that a cohort of heart allograft recipients treated with Daclizumab (a humanized anti-CD25 antibody) display FOXP3 expression patterns consistent with functional T regulatory cell populations. High levels of FOXP3 were observed to correlate with lower incidence of and recovery from acute rejection, as well as lower levels of anti-donor HLA antibody production. Therefore, T reg populations appear fully functional in patients treated with Daclizumab, even when 5 doses were administered. By comparison, patients treated with fewer doses or no Daclizumab had a higher incidence of acute rejection, antibody production and graft failure. Therefore, our data indicates that Daclizumab treatment does not interfere with the generation of regulatory T cells and has a beneficial effect on heart allograft survival.


Asunto(s)
Factores de Transcripción Forkhead/análisis , Trasplante de Corazón/inmunología , Subunidad alfa del Receptor de Interleucina-2/antagonistas & inhibidores , Linfocitos T Reguladores/inmunología , Adolescente , Adulto , Anciano , Femenino , Antígenos HLA/inmunología , Humanos , Masculino , Persona de Mediana Edad
17.
Radiol Med ; 111(4): 572-84, 2006 Jun.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-16779543

RESUMEN

PURPOSE: The aim of this study was to evaluate bone marrow reconversion in patients with obstructive sleep apnoea syndrome (OSAS) by means of magnetic resonance imaging (MRI). To our knowledge, no explicit correlation between OSAS and such parameter has been documented in the literature. MATERIALS AND METHODS: During a 35-month period, 33 patients with a clinical diagnosis of OSAS, obese but without restrictive or obstructive ventilatory defects, were evaluated with MRI during wakefulness in all patients with T1-, PD- and T2-weighted sequences in the sagittal and axial plane within 1 week after polysomnography. RESULTS: MRI showed bone marrow reconversion in 33.3% of patients. Patients with bone marrow reconversion showed higher mean haematocrit (HT) values, lower mean nocturnal oxyhaemoglobin saturation, higher percentage of sleep time with oxygen saturation (SaO2) <90%, lower nadir, as well as greater neck adiposity and soft-palate lengthening compared with patients without bone marrow reconversion. Furthermore, in patients with bone marrow reconversion, haematocrit (HT) was negatively correlated with daytime arterial oxygen partial pressure (PaO2) and positively with arterial carbon dioxide partial pressure (PaCO2). CONCLUSIONS: In patients with OSAS, bone marrow reconversion is probably correlated with the severity of nocturnal desaturation. As bone marrow reconversion is, for unknown reasons, greater in adults younger than 40 years, MRI evidence of bone marrow reconversion could be useful in young individuals for the early diagnosis of sleep-disordered breathing and prevention of associated cardiovascular diseases.


Asunto(s)
Médula Ósea/anatomía & histología , Imagen por Resonancia Magnética/métodos , Apnea Obstructiva del Sueño/patología , Adulto , Anciano , Índice de Masa Corporal , Distribución de Chi-Cuadrado , Femenino , Hematócrito , Humanos , Masculino , Persona de Mediana Edad , Obesidad/patología , Oxihemoglobinas/análisis , Polisomnografía
18.
Transplant Proc ; 37(4 Suppl): 4S-17S, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15809102

RESUMEN

Graft failure and mortality among heart transplant recipients remains higher than in populations receiving renal transplants. A major cause of graft loss is cardiac allograft vasculopathy (CAV), a condition characterized by diffuse thickening of coronary blood vessels. CAV often progresses silently, with major cardiac events (eg, ventricular arrhythmia) being the first presentation. Better diagnosis and monitoring of CAV is now possible with intravascular ultrasonography, a sensitive technique for measuring intimal thickness. To date, immunosuppressants have shown little efficacy for preventing CAV. However, a new class of agents, proliferation signal inhibitors (sirolimus and everolimus), have shown considerable efficacy in this regard and for preventing rejection. In an open-label trial, sirolimus therapy was associated with less intimal and medial proliferation than azathioprine. More robust evidence is available from a larger-scale, double-blind trial involving everolimus. At 12-month follow-up the incidence of CAV was significantly lower in patients receiving everolimus (35.7% and 30.4% for everolimus 1.5 and 3.0 mg/d vs 52.8% for azathioprine; P < .05). Sirolimus and everolimus were also associated with a lower rate of cytomegalovirus infection. As with other immunosuppressants, these agents are associated with adverse events (eg, hyperlipidemia), but they can be managed. Coadministration with calcineurin inhibitors (CNIs) can exacerbate CNI-related nephrotoxicity, but evidence suggests that everolimus administered with reduced-exposure cyclosporine in the maintenance phase preserves renal function without loss of immunosuppressive efficacy. Reduced CNI dosing in de novo patients is also a potential future benefit. Proliferation signal inhibitors have considerable potential for improving outcomes in heart transplantation.


Asunto(s)
Trasplante de Corazón/normas , División Celular , Ensayos Clínicos como Asunto , Vasos Coronarios/patología , Rechazo de Injerto/patología , Rechazo de Injerto/prevención & control , Trasplante de Corazón/inmunología , Trasplante de Corazón/patología , Humanos , Inmunosupresores/uso terapéutico , Complicaciones Posoperatorias/epidemiología , Transducción de Señal/fisiología , Trasplante Homólogo , Insuficiencia del Tratamiento , Resultado del Tratamiento
19.
Neural Netw ; 16(3-4): 365-74, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12672432

RESUMEN

Neural network models (NN) have emerged as important components for applications of adaptive control theories. Their basic generalization capability, based on acquired knowledge, together with execution rapidity and correlation ability between input stimula, are basic attributes to consider NN as an extremely powerful tool for on-line control of complex systems. By a control system point of view, not only accuracy and speed, but also, in some cases, a high level of adaptation capability is required in order to match all working phases of the whole system during its lifetime. This is particularly remarkable for a new generation ground-based telescope control system. Infact, strong changes in terms of system speed and instantaneous position error tolerance are necessary, especially in case of trajectory disturb induced by wind shake. The classical control scheme adopted in such a system is based on the proportional integral (PI) filter, already applied and implemented on a large amount of new generation telescopes, considered as a standard in this technological environment. In this paper we introduce the concept of a new approach, the neural variable structure proportional integral, (NVSPI), related to the implementation of a standard multi layer perceptron network in new generation ground-based Alt-Az telescope control systems. Its main purpose is to improve adaptive capability of the Variable structure proportional integral model, an already innovative control scheme recently introduced by authors [Proc SPIE (1997)], based on a modified version of classical PI control model, in terms of flexibility and accuracy of the dynamic response range also in presence of wind noise effects. The realization of a powerful well tested and validated telescope model simulation system allowed the possibility to directly compare performances of the two control schemes on simulated tracking trajectories, revealing extremely encouraging results in terms of NVSPI control robustness and reliability.


Asunto(s)
Modelos Teóricos , Redes Neurales de la Computación , Sistema Solar
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