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1.
Artículo en Inglés | MEDLINE | ID: mdl-37994467

RESUMEN

BACKGROUND: Orthotopic liver transplantation (OLT) is rarely indicated after hepatic trauma but it can be the only therapeutic option in some patients. There are scarce data analyzing the surgical outcomes of OLT after trauma. METHODS: We used the UNOS dataset to identify patients who underwent OLT for trauma from 1987 to 2022, and compared them to a cohort of patients transplanted for other indications. Cox proportional hazard and multivariable logistic regression analyses were performed to assess predictors of graft and patient survival. RESULTS: 72 patients underwent OLT for trauma during the study period. Patients with trauma were more frequently on mechanical ventilation at the time of transplantation (26.4% vs. 7.6%, p < 0.001) and had a greater incidence of pre-transplant portal vein thrombosis (PVT) (12.5% vs. 4%, p = 0.002). Our 4:1 matched analysis showed that trauma patients had significantly shorter wait times, higher incidence of pre-transplant PVT and prolonged length of stay (LOS). Trauma was associated with decreased overall graft survival (HR = 1.42, 95% CI = 1.01-1.98), and increased LOS (p = 0.048). There were no significant differences in long term patient survival. CONCLUSION: Unique physiological and vascular challenges after severe hepatic trauma might be associated with decreased graft survival in patients requiring liver transplantation. LEVEL OF EVIDENCE: Retrospective cohort study, III.

3.
HPB (Oxford) ; 25(8): 954-961, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37149484

RESUMEN

BACKGROUND: Biliary cysts (BC) is a rare indication for orthotopic liver transplantation (OLT). METHODS: We queried the UNOS dataset to identify patients who underwent OLT for Caroli's disease (CD) and choledochal cysts (CC). All patients with BC (CD + CC) were compared to a cohort of patients transplanted for other indications. Patients with CC were also compared to those with CD. Cox proportional hazard model was performed to assess predictors of graft and patient survival. RESULTS: 261 patients underwent OLT for BC. Patients with BC had better pre-operative liver function compared to those transplanted for other indications. 5-year graft and patient survival were 72% and 81%, respectively, similar to those transplanted for other indications after matching. Patients with CC were younger and had increased preoperative cholestasis compared to those with CD. Donor age, race, and gender were predictors of poor graft and patient survival in patients transplanted for CC. CONCLUSIONS: Patients with BC have similar outcomes to those transplanted for other indications and more frequently require MELD score exception. In patients transplanted for choledochal cysts, female gender, donor age, and African-American race were independent predictors of poor survival. Pediatric patients transplanted for Caroli's disease had better survival compared to adults.


Asunto(s)
Enfermedad de Caroli , Quiste del Colédoco , Trasplante de Hígado , Adulto , Humanos , Niño , Femenino , Trasplante de Hígado/efectos adversos , Enfermedad de Caroli/cirugía , Quiste del Colédoco/cirugía , Hígado , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Supervivencia de Injerto
4.
J Allergy Clin Immunol Pract ; 11(5): 1376-1383, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37001639

RESUMEN

Managing atopic dermatitis (AD) in patients with skin of color presents unique challenges for the clinician. There is increasing evidence that AD has higher prevalence, persistence, and severity among skin of color populations. This is likely to be partly related to differences in living conditions and exposure to irritants and allergens, among other factors. Assessment of AD severity in patients with darker skin can be challenging, in particular the assessment of erythema, leading to the potential for underscoring AD severity. Variations in disease have also been described, with the potential for a greater risk of inflammation-induced nodularity and hyper- or hypopigmentation. Management challenges include variable adherence to treatment, potential disparities in access to health care, and differences in the metabolism of cyclosporine. Optimal management of AD in patients with skin of color requires a tailored approach. Here, we review approaches to diagnosing AD, evaluating extent and severity with subjective and objective measures, considering treatment options for patients with skin of color, and highlighting areas for improvement in AD care for skin of color populations.


Asunto(s)
Dermatitis Atópica , Humanos , Dermatitis Atópica/diagnóstico , Dermatitis Atópica/epidemiología , Dermatitis Atópica/terapia , Pigmentación de la Piel , Piel , Eritema , Alérgenos
7.
Nat Commun ; 13(1): 5887, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-36202846

RESUMEN

The development of a fertilized egg to an embryo requires the proper temporal control of gene expression. During cell differentiation, timing is often controlled via cascades of transcription factors (TFs). However, in early development, transcription is often inactive, and many TF levels stay constant, suggesting that alternative mechanisms govern the observed rapid and ordered onset of gene expression. Here, we find that in early embryonic development access of maternally deposited nuclear proteins to the genome is temporally ordered via importin affinities, thereby timing the expression of downstream targets. We quantify changes in the nuclear proteome during early development and find that nuclear proteins, such as TFs and RNA polymerases, enter the nucleus sequentially. Moreover, we find that the timing of nuclear proteins' access to the genome corresponds to the timing of downstream gene activation. We show that the affinity of proteins to importin is a major determinant in the timing of protein entry into embryonic nuclei. Thus, we propose a mechanism by which embryos encode the timing of gene expression in early development via biochemical affinities. This process could be critical for embryos to organize themselves before deploying the regulatory cascades that control cell identities.


Asunto(s)
Núcleo Celular , Proteoma , Transporte Activo de Núcleo Celular , Núcleo Celular/metabolismo , ARN Polimerasas Dirigidas por ADN/metabolismo , Femenino , Genoma , Humanos , Carioferinas/genética , Carioferinas/metabolismo , Proteínas Nucleares/metabolismo , Embarazo , Proteoma/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
8.
World J Surg ; 46(12): 3081-3089, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36209339

RESUMEN

BACKGROUND: Post-hepatectomy liver failure (PHLF) is associated with high mortality following liver resection. There have been limited studies evaluating predictors of PHLF and clinically significant PHLF in non-cirrhotic patients. METHODS: This was a retrospective cohort study using the National Surgical Quality Improvement Program database (NSQIP) to evaluate 8,093 non-cirrhotic patients undergoing hepatectomy from 2014 to 2018. Primary endpoints were PHLF and clinically significant PHLF (PHLF grade B or C). RESULTS: Among all patients, 4.74% (n = 383) developed PHLF and 2.5% clinically significant PHLF (n = 203). The overall 30-day mortality was 1.35% (n = 109), 11.5% (n = 44) in patients with PHLF, and 19.2% in those with clinically significant PHLF. Factors associated with PHLF were: metastatic liver disease (OR = 1.84, CI = 1.14-2.98), trisectionectomy (OR = 3.71, CI = 2.59-5.32), right total lobectomy (OR = 4.17, CI = 3.06-5.68), transfusions (OR = 1.99, CI = 1.52-2.62), organ/space SSI (OR = 2.84, CI = 2.02-3.98), post-operative pneumonia (OR = 2.43, CI = 1.57-3.76), sepsis (OR = 2.27, CI = 1.47-3.51), and septic shock (OR = 5.67, CI = 3.43-9.36). Patients who developed PHLF or clinically significant PHLF had 2-threefold increased risk of perioperative mortality. Post-hepatectomy renal failure (OR = 8.47, CI = 3.96-18.1), older age (OR = 1.04, CI = 1.014-1.063), male sex (OR = 1.83, CI = 1.07-3.14), sepsis (OR = 2.96, CI = 1.22-7.2), and septic shock (OR = 3.92, CI = 1.61-9.58) were independently associated with 30-mortality in patients with clinically significant PHLF. CONCLUSION: PHLF in non-cirrhotic patients increased the risk of perioperative mortality and is associated with the extent of hepatectomy and infectious complications. Careful evaluation of the liver remnant, antibiotic prophylaxis, nutritional assessment, and timely management of post-operative infections could decrease major morbidity and mortality following hepatectomy.


Asunto(s)
Fallo Hepático , Neoplasias Hepáticas , Choque Séptico , Humanos , Masculino , Hepatectomía/efectos adversos , Estudios Retrospectivos , Choque Séptico/complicaciones , Fallo Hepático/etiología , Fallo Hepático/cirugía , Neoplasias Hepáticas/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
9.
Cell ; 185(18): 3441-3456.e19, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36055202

RESUMEN

Great progress has been made in understanding gut microbiomes' products and their effects on health and disease. Less attention, however, has been given to the inputs that gut bacteria consume. Here, we quantitatively examine inputs and outputs of the mouse gut microbiome, using isotope tracing. The main input to microbial carbohydrate fermentation is dietary fiber and to branched-chain fatty acids and aromatic metabolites is dietary protein. In addition, circulating host lactate, 3-hydroxybutyrate, and urea (but not glucose or amino acids) feed the gut microbiome. To determine the nutrient preferences across bacteria, we traced into genus-specific bacterial protein sequences. We found systematic differences in nutrient use: most genera in the phylum Firmicutes prefer dietary protein, Bacteroides dietary fiber, and Akkermansia circulating host lactate. Such preferences correlate with microbiome composition changes in response to dietary modifications. Thus, diet shapes the microbiome by promoting the growth of bacteria that preferentially use the ingested nutrients.


Asunto(s)
Microbioma Gastrointestinal , Animales , Bacterias , Dieta , Fibras de la Dieta/metabolismo , Proteínas en la Dieta/metabolismo , Lactatos/metabolismo , Ratones , Nutrientes
10.
Front Immunol ; 13: 883855, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35720387

RESUMEN

Numerous preclinical studies have provided solid evidence supporting adoptive transfer of regulatory T cells (Tregs) to induce organ tolerance. As a result, there are 7 currently active Treg cell-based clinical trials in solid organ transplantation worldwide, all of which are early phase I or phase I/II trials. Although the results of these trials are optimistic and support both safety and feasibility, many experimental and clinical unanswered questions are slowing the progression of this new therapeutic alternative. In this review, we bring to the forefront the major challenges that Treg cell transplant investigators are currently facing, including the phenotypic and functional diversity of Treg cells, lineage stability, non-standardized ex vivo Treg cell manufacturing process, adequacy of administration route, inability of monitoring and tracking infused cells, and lack of biomarkers or validated surrogate endpoints of efficacy in clinical trials. With this plethora of interrogation marks, we are at a challenging and exciting crossroad where properly addressing these questions will determine the successful implementation of Treg cell-based immunotherapy in clinical transplantation.


Asunto(s)
Trasplante de Órganos , Linfocitos T Reguladores , Traslado Adoptivo , Tolerancia Inmunológica , Inmunoterapia
11.
Front Med (Lausanne) ; 9: 803016, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35602513

RESUMEN

Cardiovascular disease and mineral bone disorders are major contributors to morbidity and mortality among patients with chronic kidney disease and often persist after renal transplantation. Ongoing hormonal imbalances after kidney transplant (KT) are associated with loss of graft function and poor outcomes. Fibroblast growth factor 23 (FGF-23) and its co-receptor, α-Klotho, are key factors in the underlying mechanisms that integrate accelerated atherosclerosis, vascular calcification, mineral disorders, and osteodystrophy. On the other hand, kidney donation is also associated with endocrine and metabolic adaptations that include transient increases in circulating FGF-23 and decreases in α-Klotho levels. However, the long-term impact of these alterations and their clinical relevance have not yet been determined. This manuscript aims to review and summarize current data on the role of FGF-23 and α-Klotho in the endocrine response to KT and living kidney donation, and importantly, underscore specific areas of research that may enhance diagnostics and therapeutics in the growing population of KT recipients and kidney donors.

12.
J Am Coll Surg ; 234(5): 892-899, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426403

RESUMEN

BACKGROUND: Orthotopic liver transplantation (OLT) is the accepted treatment in patients with unresectable, early-stage hepatocellular carcinoma (HCC) in the setting of cirrhosis. Due to increasing waitlist demand for OLT, determining optimal groups for transplant is critical. Elderly patients are known to have poorer postoperative outcomes. Considering the effectiveness of liver-directed therapies for HCC, we sought to determine whether elderly patients received survival benefit from OLT over liver-directed therapy alone. STUDY DESIGN: The National Cancer Database participant use file was used to analyze data between 2004 and 2017. Only patients ≥70 years of age who received OLT or liver-directed therapy alone were included. Patients with alpha-fetoprotein >500 ng/mL or missing alpha-fetoprotein values were excluded. Baseline demographic variables, model for end-stage liver disease score, and overall survival from time of diagnosis were collected. Descriptive statistics, Kaplan-Meier survival, Cox proportional hazards model, and propensity score matching were used. RESULTS: A total of 2,377 patients received ablative therapy alone, and 214 patients received OLT. Multivariable analysis and Kaplan-Meier showed that OLT conferred a significant survival benefit compared to liver-directed therapy alone. Age was also associated with a yearly 3% increase in risk of mortality. Propensity-matched analysis adjusting also demonstrated a significant survival benefit for elderly patients receiving OLT compared to liver-directed therapy alone. CONCLUSION: Despite increased age and associated comorbidities being factors associated with poor outcomes, OLT confers a survival advantage compared to liver-directed ablative therapies alone in selected elderly patients with HCC. OLT should be offered in medically appropriate elderly patients with HCC.


Asunto(s)
Carcinoma Hepatocelular , Enfermedad Hepática en Estado Terminal , Neoplasias Hepáticas , Trasplante de Hígado , Anciano , Enfermedad Hepática en Estado Terminal/etiología , Enfermedad Hepática en Estado Terminal/cirugía , Humanos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , alfa-Fetoproteínas
13.
J Allergy Clin Immunol Pract ; 10(2): 566-576.e6, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34890827

RESUMEN

BACKGROUND: The maximum tolerated dose of peanut protein following peanut oral immunotherapy (POIT) is unknown because most research studies have not examined very high thresholds. OBJECTIVE: To define the maximum dose tolerated by patients on POIT and severity of allergic reactions after a 1-month period of treatment discontinuation. METHODS: In a phase 2 3-year POIT open-label study, we enrolled participants age 5 to 13 years with a 1-year build-up period followed by a 2-year daily maintenance dose of 3900 mg with assessment of the maximum tolerated dose using double-blind placebo-controlled food challenges (DBPCFCs) of 26,225 mg cumulative dose of peanut protein. The DBPCFC was performed at baseline, after 12-month build-up, at 2 year of maintenance, and after a 1-month period of treatment discontinuation. Biomarkers were assessed every 6 weeks for the first 6 months of therapy. A general linear mixed model was used for analysis. RESULTS: The mean maximum cumulative tolerated dose after 12 months increased by 12,063 mg (P < .001) (n = 12), slightly decreased during maintenance (n = 11), and significantly decreased by 7593 mg after avoidance for 1 month (P = .03) (n = 6). Biomarker analysis revealed decreases in cytokine expression within the first 6 weeks of initiation of POIT and decreased peanut-IgG4 and increased cytokine expression after 1 month of discontinuation. The DBPCFC reaction severity, examined through a symptom score with 1 point for each defined symptom, decreased after 12 months, but did not significantly change after 1 month of POIT discontinuation. CONCLUSIONS: The evaluation of POIT and sustained unresponsiveness by maximum tolerated dose by DBPCFCs in this small phase 2 trial showed that desensitization is diminished, with 100% loss of tolerated dose after 1 month of avoidance following 3 years of treatment.


Asunto(s)
Arachis , Hipersensibilidad al Cacahuete , Administración Oral , Adolescente , Alérgenos , Niño , Preescolar , Desensibilización Inmunológica/efectos adversos , Humanos , Hipersensibilidad al Cacahuete/terapia
14.
Front Pediatr ; 9: 646997, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34660469

RESUMEN

The efficacy of dupilumab in pediatric patients with severe eczema presenting in the setting of elevated immunoglobulin E (IgE) levels and recurrent bacterial skin infections is not well-understood. Here we present the case of a child with elevated IgE levels in whom dupilumab treatment led to remarkable control of his eczema and recurrent skin infections. We also review the use of dupilumab in other patients with molecularly proven cases of hyper IgE (HIGE) syndrome. Our case supports the notion that dupilumab may have a seminal application in treating severe eczema that occurs in the setting of elevated IgE levels and recurrent bacterial skin infections.

15.
World J Surg ; 45(12): 3654-3659, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34546385

RESUMEN

BACKGROUND: To determine the impact of hepatic steatosis on perioperative outcomes of patients undergoing hepatectomy. METHODS: We analyzed all hepatectomy patients with normal and fatty liver texture, between 2014 and 2018 using NSQIP. Main endpoints included perioperative transfusions (within 72 h) and infectious complications. RESULTS: A total of 8,237 patients underwent hepatectomy during the study period. The overall rate of fatty liver texture (FLG) was 31% (2,557). Operative duration was significantly longer; inflow occlusion was more common (Pringle maneuver), and the need of transfusions was significantly higher in the FLG compared to the normal liver group (NLG) (p = < 0.001). On multivariate analysis, patients in the FLG had increased risk of developing infectious complications (OR 1.22 [95%IC 1.05-1.41]) and transfusion requirements within 72 h after hepatectomy (OR 1.43 [95% CI 1.24-1.63]). CONCLUSIONS: Hepatic steatosis is an independent risk factor for the development of infectious complications and increased perioperative transfusion requirements in patients undergoing hepatectomy. Those requiring transfusions within 72 h had also an increased risk of infections after hepatectomy.


Asunto(s)
Hígado Graso , Neoplasias Hepáticas , Pérdida de Sangre Quirúrgica , Hígado Graso/epidemiología , Hepatectomía/efectos adversos , Humanos , Neoplasias Hepáticas/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología
16.
Mol Syst Biol ; 17(8): e9895, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34414660

RESUMEN

The famous Arrhenius equation is well suited to describing the temperature dependence of chemical reactions but has also been used for complicated biological processes. Here, we evaluate how well the simple Arrhenius equation predicts complex multi-step biological processes, using frog and fruit fly embryogenesis as two canonical models. We find that the Arrhenius equation provides a good approximation for the temperature dependence of embryogenesis, even though individual developmental intervals scale differently with temperature. At low and high temperatures, however, we observed significant departures from idealized Arrhenius Law behavior. When we model multi-step reactions of idealized chemical networks, we are unable to generate comparable deviations from linearity. In contrast, we find the two enzymes GAPDH and ß-galactosidase show non-linearity in the Arrhenius plot similar to our observations of embryonic development. Thus, we find that complex embryonic development can be well approximated by the simple Arrhenius equation regardless of non-uniform developmental scaling and propose that the observed departure from this law likely results more from non-idealized individual steps rather than from the complexity of the system.


Asunto(s)
Temperatura
17.
Liver Transpl ; 27(12): 1824-1829, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34097811

RESUMEN

The combination of rising rates of obesity and the shortage of deceased donor livers have forced the consideration of marginal liver donors in terms of body mass index (BMI) for liver transplantation (LT). To date, there are still conflicting data on the impact of donor obesity on post-LT outcomes. We analyzed all patients undergoing LT alone in the United States (US) from October 2005 through December 2019 using the United Network of Organ Sharing (UNOS) data set. We categorized donor BMI >40 kg/m2 as extremely obese (EO). Primary endpoints included 30-day perioperative mortality and early graft loss (EGL) within 7 days. A subgroup analysis was performed for the EO donor group to assess how macrovesicular steatosis (MaS) >30% affects 30-day mortality and EGL within 7 days. A total of 72,616 patients underwent LT during the study period. The 30-day perioperative mortality was significantly higher in the EO donor group (P = 0.02). On multivariate analysis, recipients undergoing LT with EO donors had a 38% higher 30-day mortality risk (odds ratio [OR], 1.38; 95% confidence interval [CI], 1.21-1.69) and 53% increased risk of EGL (OR, 1.53; 95% CI, 1.22-1.90). MaS >30% was independently associated with a 2-fold increased risk of 30-day mortality (P = 0.003) and 3.5-fold increased risk of EGL within 7 days (P < 0.001). The impact of MaS >30% in EGL was 2-fold for all patients transplanted during the study period compared with 3.5-fold in the EO donor group. There is an increased risk of EGL and 30-day perioperative mortality in recipients transplanted with EO donors. Future studies are warranted in morbid and super obese donors to assess the possible effect of obesity-related proinflammatory factors in EGL.


Asunto(s)
Trasplante de Hígado , Supervivencia de Injerto , Humanos , Hígado/cirugía , Trasplante de Hígado/efectos adversos , Obesidad/complicaciones , Estudios Retrospectivos , Factores de Riesgo , Donantes de Tejidos , Resultado del Tratamiento , Estados Unidos/epidemiología
18.
Contemp Clin Trials ; 100: 106228, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33242697

RESUMEN

Asthma remains one of the most important challenges to pediatric public health in the US. A large majority of children with persistent and chronic asthma demonstrate aeroallergen sensitization, which remains a pivotal risk factor associated with the development of persistent, progressive asthma throughout life. In individuals with a tendency toward Type 2 inflammation, sensitization and exposure to high concentrations of offending allergens is associated with increased risk for development of, and impairment from, asthma. The cascade of biological responses to allergens is primarily mediated through IgE antibodies and their production is further stimulated by IgE responses to antigen exposure. In addition, circulating IgE impairs innate anti-viral immune responses. The latter effect could magnify the effects of another early life exposure associated with increased risk of the development of asthma - viral infections. Omalizumab binds to circulating IgE and thus ablates antigen signaling through IgE-related mechanisms. Further, it has been shown restore IFN-α response to rhinovirus and to reduce asthma exacerbations during the viral season. We therefore hypothesized that early blockade of IgE and IgE mediated responses with omalizumab would prevent the development and reduce the severity of asthma in those at high risk for developing asthma. Herein, we describe a double-blind, placebo-controlled trial of omalizumab in 2-3 year old children at high risk for development of asthma to prevent the development and reduce the severity of asthma. We describe the rationale, methods, and lessons learned in implementing this potentially transformative trial aimed at prevention of asthma.


Asunto(s)
Antiasmáticos , Asma , Antiasmáticos/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Asma/tratamiento farmacológico , Asma/prevención & control , Niño , Humanos , Inmunoglobulina E , Omalizumab/uso terapéutico
19.
J Gastrointest Surg ; 25(6): 1487-1493, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32632728

RESUMEN

BACKGROUND: Neuroendocrine tumor (NET) metastases are a major cause of morbidity and mortality. The role of liver transplantation to treat unresectable metastases from NET is controversial. METHODS: We evaluated outcomes of all patients undergoing "isolated" liver transplantation (LT) for metastatic NETs in the USA, from October 1988 through June 2018 using the UNOS dataset. RESULTS: During the study period, 160,360 LTs were performed. Two hundred six adult patients underwent "isolated" LT for metastatic NETs. The mean (SD) age was 48.2 (11.7) years, ranging from 19 to 75 years; 117 (56.8%) patients were male. Overall 1-, 3-, 5-, and 10-year patient survival rates were 89.1%, 75.3%, 64.9%, and 46.1%, respectively. Tumor recurrence was seen in 70 of 206 patients who underwent LT (34%). The median time to recurrence was 28 months (range, 1 to 192 months) and median wait time for LT was 112 days. Tumor recurrence was significantly higher in transplanted patients waiting less than 6 months compared with those waiting more than 6 months (74.3% vs. 25.7%). Patients' age ≤ 45 years had significantly better survival compared with those > 45 years (p = 0.03). Younger patients with carcinoid tumors had better survival but this trend was not observed in the non-carcinoid group. On multivariable analysis, recipient age, donor age, cold ischemic time MELD score, and tumor recurrence were significant predictors of poor patient survival. CONCLUSIONS: Waiting time longer than 6 months is associated to lower rates of tumor recurrence. Younger patients ≤ 45 years had significantly improved survival after LT for NET metastases.


Asunto(s)
Neoplasias Hepáticas , Trasplante de Hígado , Tumores Neuroendocrinos , Adulto , Humanos , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Tumores Neuroendocrinos/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
20.
Proc Natl Acad Sci U S A ; 117(31): 18737-18743, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32675245

RESUMEN

The outer membrane (OM) of gram-negative bacteria confers innate resistance to toxins and antibiotics. Integral ß-barrel outer membrane proteins (OMPs) function to establish and maintain the selective permeability of the OM. OMPs are assembled into the OM by the ß-barrel assembly machine (BAM), which is composed of one OMP-BamA-and four lipoproteins-BamB, C, D, and E. BamB, C, and E can be removed individually with only minor effects on barrier function; however, depletion of either BamA or BamD causes a global defect in OMP assembly and results in cell death. We have identified a gain-of-function mutation, bamAE470K , that bypasses the requirement for BamD. Although bamD::kan bamAE470K cells exhibit growth and OM barrier defects, they assemble OMPs with surprising robustness. Our results demonstrate that BamD does not play a catalytic role in OMP assembly, but rather functions to regulate the activity of BamA.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa , Membrana Externa Bacteriana , Proteínas de Escherichia coli , Mutación con Ganancia de Función/genética , Membrana Externa Bacteriana/química , Membrana Externa Bacteriana/metabolismo , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas de la Membrana Bacteriana Externa/metabolismo , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo
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