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1.
Proc Natl Acad Sci U S A ; 121(18): e2317690121, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38648485

RESUMEN

The underlying mechanism(s) by which the PML::RARA fusion protein initiates acute promyelocytic leukemia is not yet clear. We defined the genomic binding sites of PML::RARA in primary mouse and human hematopoietic progenitor cells with V5-tagged PML::RARA, using anti-V5-PML::RARA chromatin immunoprecipitation sequencing and CUT&RUN approaches. Most genomic PML::RARA binding sites were found in regions that were already chromatin-accessible (defined by ATAC-seq) in unmanipulated, wild-type promyelocytes, suggesting that these regions are "open" prior to PML::RARA expression. We found that GATA binding motifs, and the direct binding of the chromatin "pioneering factor" GATA2, were significantly enriched near PML::RARA binding sites. Proximity labeling studies revealed that PML::RARA interacts with ~250 proteins in primary mouse hematopoietic cells; GATA2 and 33 others require PML::RARA binding to DNA for the interaction to occur, suggesting that binding to their cognate DNA target motifs may stabilize their interactions. In the absence of PML::RARA, Gata2 overexpression induces many of the same epigenetic and transcriptional changes as PML::RARA. These findings suggested that PML::RARA may indirectly initiate its transcriptional program by activating Gata2 expression: Indeed, we demonstrated that inactivation of Gata2 prior to PML::RARA expression prevented its ability to induce self-renewal. These data suggested that GATA2 binding creates accessible chromatin regions enriched for both GATA and Retinoic Acid Receptor Element motifs, where GATA2 and PML::RARA can potentially bind and interact with each other. In turn, PML::RARA binding to DNA promotes a feed-forward transcriptional program by positively regulating Gata2 expression. Gata2 may therefore be required for PML::RARA to establish its transcriptional program.


Asunto(s)
Factor de Transcripción GATA2 , Células Madre Hematopoyéticas , Proteínas de Fusión Oncogénica , Animales , Humanos , Ratones , Sitios de Unión , Autorrenovación de las Células , Cromatina/metabolismo , ADN/metabolismo , Factor de Transcripción GATA2/metabolismo , Factor de Transcripción GATA2/genética , Células Madre Hematopoyéticas/metabolismo , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patología , Proteínas de Fusión Oncogénica/metabolismo , Proteínas de Fusión Oncogénica/genética , Proteína de la Leucemia Promielocítica/metabolismo , Proteína de la Leucemia Promielocítica/genética , Unión Proteica , Receptor alfa de Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico/genética
2.
Proc Natl Acad Sci U S A ; 120(21): e2208276120, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37186859

RESUMEN

Iron-chalcogenide superconductors FeSe1-xSx possess unique electronic properties such as nonmagnetic nematic order and its quantum critical point. The nature of superconductivity with such nematicity is important for understanding the mechanism of unconventional superconductivity. A recent theory suggested the possible emergence of a fundamentally new class of superconductivity with the so-called Bogoliubov Fermi surfaces (BFSs) in this system. However, such an ultranodal pair state requires broken time-reversal symmetry (TRS) in the superconducting state, which has not been observed experimentally. Here, we report muon spin relaxation (µSR) measurements in FeSe1-xSx superconductors for 0 ≤ x ≤ 0.22 covering both orthorhombic (nematic) and tetragonal phases. We find that the zero-field muon relaxation rate is enhanced below the superconducting transition temperature Tc for all compositions, indicating that the superconducting state breaks TRS both in the nematic and tetragonal phases. Moreover, the transverse-field µSR measurements reveal that the superfluid density shows an unexpected and substantial reduction in the tetragonal phase (x > 0.17). This implies that a significant fraction of electrons remain unpaired in the zero-temperature limit, which cannot be explained by the known unconventional superconducting states with point or line nodes. The TRS breaking and the suppressed superfluid density in the tetragonal phase, together with the reported enhanced zero-energy excitations, are consistent with the ultranodal pair state with BFSs. The present results reveal two different superconducting states with broken TRS separated by the nematic critical point in FeSe1-xSx, which calls for the theory of microscopic origins that account for the relation between nematicity and superconductivity.

3.
Blood ; 140(13): 1533-1548, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-35895896

RESUMEN

We have developed a deep-scale proteome and phosphoproteome database from 44 representative acute myeloid leukemia (AML) patients from the LAML TCGA dataset and 6 healthy bone marrow-derived controls. After confirming data quality, we orthogonally validated several previously undescribed features of AML revealed by the proteomic data. We identified examples of posttranscriptionally regulated proteins both globally (ie, in all AML samples) and also in patients with recurrent AML driver mutations. For example, samples with IDH1/2 mutations displayed elevated levels of the 2-oxoglutarate-dependent histone demethylases KDM4A/B/C, despite no changes in messenger RNA levels for these genes; we confirmed this finding in vitro. In samples with NPMc mutations, we identified several nuclear importins with posttranscriptionally increased protein abundance and showed that they interact with NPMc but not wild-type NPM1. We identified 2 cell surface proteins (CD180 and MRC1/CD206) expressed on AML blasts of many patients (but not healthy CD34+ stem/progenitor cells) that could represent novel targets for immunologic therapies and confirmed these targets via flow cytometry. Finally, we detected nearly 30 000 phosphosites in these samples; globally, AML samples were associated with the abnormal phosphorylation of specific residues in PTPN11, STAT3, AKT1, and PRKCD. FLT3-TKD samples were associated with increased phosphorylation of activating tyrosines on the cytoplasmic Src-family tyrosine kinases FGR and HCK and related signaling proteins. PML-RARA-initiated AML samples displayed a unique phosphorylation signature, and TP53-mutant samples showed abundant phosphorylation of serine-183 on TP53 itself. This publicly available database will serve as a foundation for further investigations of protein dysregulation in AML pathogenesis.


Asunto(s)
Leucemia Mieloide Aguda , Proteínas Nucleares , Histona Demetilasas/metabolismo , Humanos , Histona Demetilasas con Dominio de Jumonji , Carioferinas/genética , Ácidos Cetoglutáricos , Leucemia Mieloide Aguda/patología , Proteínas de la Membrana/genética , Mutación , Proteínas Nucleares/genética , Nucleofosmina , Proteoma/metabolismo , Proteómica , ARN Mensajero , Serina/genética , Tirosina Quinasa 3 Similar a fms/genética , Familia-src Quinasas/metabolismo
4.
Proc Natl Acad Sci U S A ; 118(49)2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34845035

RESUMEN

Acute myeloid leukemia (AML) patients rarely have long first remissions (LFRs; >5 y) after standard-of-care chemotherapy, unless classified as favorable risk at presentation. Identification of the mechanisms responsible for long vs. more typical, standard remissions may help to define prognostic determinants for chemotherapy responses. Using exome sequencing, RNA-sequencing, and functional immunologic studies, we characterized 28 normal karyotype (NK)-AML patients with >5 y first remissions after chemotherapy (LFRs) and compared them to a well-matched group of 31 NK-AML patients who relapsed within 2 y (standard first remissions [SFRs]). Our combined analyses indicated that genetic-risk profiling at presentation (as defined by European LeukemiaNet [ELN] 2017 criteria) was not sufficient to explain the outcomes of many SFR cases. Single-cell RNA-sequencing studies of 15 AML samples showed that SFR AML cells differentially expressed many genes associated with immune suppression. The bone marrow of SFR cases had significantly fewer CD4+ Th1 cells; these T cells expressed an exhaustion signature and were resistant to activation by T cell receptor stimulation in the presence of autologous AML cells. T cell activation could be restored by removing the AML cells or blocking the inhibitory major histocompatibility complex class II receptor, LAG3. Most LFR cases did not display these features, suggesting that their AML cells were not as immunosuppressive. These findings were confirmed and extended in an independent set of 50 AML cases representing all ELN 2017 risk groups. AML cell-mediated suppression of CD4+ T cell activation at presentation is strongly associated with unfavorable outcomes in AML patients treated with standard chemotherapy.


Asunto(s)
Tolerancia Inmunológica/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/inmunología , Adulto , Linfocitos T CD4-Positivos/inmunología , Femenino , Humanos , Tolerancia Inmunológica/inmunología , Cariotipo , Leucemia Mieloide Aguda/terapia , Masculino , Persona de Mediana Edad , Pronóstico , Recurrencia , Inducción de Remisión , Factores de Riesgo , Análisis de Secuencia de ARN/métodos , Células TH1/inmunología , Transcriptoma/genética , Resultado del Tratamiento
5.
Ann Surg ; 278(5): e1110-e1117, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36806227

RESUMEN

OBJECTIVE: To evaluate whether patients with advanced cancer prefer surgeons to use the best case/worst case (BC/WC) communication framework over the traditional risk/benefit (R/B) framework in the context of palliative surgical scenarios. BACKGROUND: Identifying the patient's preferred communication frameworks may improve satisfaction and outcome measures during difficult clinical decision-making. METHODS: In a video-vignette-based randomized, double-blinded study from November 2020 to May 2021, patients with advanced cancer viewed 2 videos depicting a physician-patient encounter in a palliative surgical scenario, in which the surgeon uses either the BC/WC or the R/B framework to discuss treatment options. The primary outcome was the patients' preferred video surgeon. RESULTS: One hundred fifty-five patients were approached to participate; 66 were randomized and 58 completed the study (mean age 55.8 ± 13.8 years, 60.3% males). 22 patients (37.9%, 95% CI: 25.4%-50.4%) preferred the surgeon using the BC/WC framework, 21 (36.2%, 95% CI: 23.8%-48.6%) preferred the surgeon using the R/B framework, and 15 (25.9%, 95% CI: 14.6%-37.2%) indicated no preference. High trust in the medical profession was inversely associated with a preference for the surgeon using BC/WC framework (odds ratio: 0.83, 95% CI: 0.70-0.98, P = 0.03). The BC/WC framework rated higher for perceived surgeon's listening (4.6 ± 0.7 vs 4.3±0.9, P = 0.03) and confidence in the surgeon's trustworthiness (4.3 ± 0.8 vs 4.0 ± 0.9, P = 0.04). CONCLUSIONS: Surgeon use of the BC/WC communication framework was not universally preferred but was as acceptable to patients as the traditional R/B framework and rated higher in certain aspects of communication. A preference for a surgeon using BC/WC was associated with lower trust in the medical profession. Surgeons should consider the BC/WC framework to individualize their approach to challenging clinical discussions.


Asunto(s)
Neoplasias , Cirujanos , Masculino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Femenino , Pacientes , Neoplasias/cirugía , Relaciones Médico-Paciente , Comunicación
6.
Blood ; 138(13): 1148-1161, 2021 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-34125173

RESUMEN

Most patients with acute promyelocytic leukemia (APL) can be cured with combined all-trans retinoic acid (ATRA) and arsenic trioxide therapy, which induces the destruction of PML-RARA, the initiating fusion protein for this disease. However, the underlying mechanisms by which PML-RARA initiates and maintains APL cells are still not clear. Therefore, we identified genes that are dysregulated by PML-RARA in mouse and human APL cells and prioritized GATA2 for functional studies because it is highly expressed in preleukemic cells expressing PML-RARA, its high expression persists in transformed APL cells, and spontaneous somatic mutations of GATA2 occur during APL progression in mice and humans. These and other findings suggested that GATA2 may be upregulated to thwart the proliferative signal generated by PML-RARA and that its inactivation by mutation (and/or epigenetic silencing) may accelerate disease progression in APL and other forms of acute myeloid leukemia (AML). Indeed, biallelic knockout of Gata2 with CRISPR/Cas9-mediated gene editing increased the serial replating efficiency of PML-RARA-expressing myeloid progenitors (as well as progenitors expressing RUNX1-RUNX1T1, or deficient for Cebpa), increased mouse APL penetrance, and decreased latency. Restoration of Gata2 expression suppressed PML-RARA-driven aberrant self-renewal and leukemogenesis. Conversely, addback of a mutant GATA2R362G protein associated with APL and AML minimally suppressed PML-RARA-induced aberrant self-renewal, suggesting that it is a loss-of-function mutation. These studies reveal a potential role for Gata2 as a tumor suppressor in AML and suggest that restoration of its function (when inactivated) may provide benefit for AML patients.


Asunto(s)
Factor de Transcripción GATA2/genética , Leucemia Promielocítica Aguda/genética , Animales , Sistemas CRISPR-Cas , Línea Celular Tumoral , Progresión de la Enfermedad , Factor de Transcripción GATA2/metabolismo , Regulación Leucémica de la Expresión Génica , Genes Supresores de Tumor , Humanos , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patología , Ratones , Mutación
7.
Ann Surg ; 274(1): 155-161, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31361626

RESUMEN

BACKGROUND: Histologic subtypes of appendiceal cancer vary in their propensity for metastases to regional lymph nodes (LN). A predictive model would help direct subsequent surgical therapy. METHODS: The National Cancer Database was queried for patients with appendiceal cancer undergoing surgery between 1998 and 2012. Multivariable logistic regression was used to develop a predictive model of LN metastases which was internally validated using Brier score and Area under the Curve (AUC). RESULTS: A total of 21,647 patients were identified, of whom 9079 (41.9%) had node negative disease, 4575 (21.1%) node positive disease, and 7993 (36.9%) unknown LN status. The strongest predictors of LN positivity were histology (carcinoid tumors OR 12.78, 95% CI 9.01-18.12), increasing T Stage (T3 OR 3.36, 95% CI 2.52-4.50, T4 OR 6.30, 95% CI 4.71-8.42), and tumor grade (G3 OR 5.55, 95% CI 4.78-6.45, G4 OR 5.98, 95% CI 4.30-8.31). The coefficients from the regression analysis were used to construct a calculator that generated predicted probabilities of LN metastases given certain inputs. Internal validation of the overall model showed an AUC of 0.75 (95% CI 0.74-0.76) and Brier score of 0.188. Histology-specific predictive models were also constructed with an AUC that varied from 0.669 for signet cell to 0.75 for goblet cell tumors. CONCLUSIONS: The risk for nodal metastases in patients with appendiceal cancers can be quantified with reasonable accuracy using a predictive model incorporating patient age, sex, tumor histology, T-stage, and grade. This can help inform clinical decision making regarding the need for a right hemicolectomy following appendectomy.


Asunto(s)
Neoplasias del Apéndice/patología , Técnicas de Apoyo para la Decisión , Metástasis Linfática , Anciano , Anciano de 80 o más Años , Neoplasias del Apéndice/cirugía , Toma de Decisiones Clínicas , Colectomía , Toma de Decisiones Conjunta , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Análisis de Regresión
8.
Ann Surg Oncol ; 27(1): 303-312, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31605328

RESUMEN

BACKGROUND: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has been associated with increased postoperative complications and a prolonged length of stay (LOS). We report on our experience following implementation of an Enhanced Recovery After Surgery (ERAS) program for CRS and HIPEC. METHODS: Patients were divided into pre- and post-ERAS groups. Modifications in the ERAS group included routine use of transversus abdominis plane blocks, intra- and postoperative fluid restriction, and minimizing the use of narcotics, drains, and nasogastric tubes. RESULTS: Of a total of 130 procedures, 49 (38%) were in the pre-ERAS group and 81 (62%) were in the ERAS group. Mean LOS was reduced from 10.3 ± 8.9 days to 6.9 ± 5.0 days (p = 0.007) and the rate of grade III/IV complications was reduced from 24 to 15% (p = 0.243) following ERAS implementation. The ERAS group received less intravenous fluid during hospitalization (19.2 ± 18.7 L vs. 32.8 ± 32.5 L, p = 0.003) and used less opioids than the pre-ERAS group (median of 159.7 mg of oral morphine equivalents vs. 272.6 mg). There were no significant changes in the rates of 30-day readmission or acute kidney injury between the two groups (p = non-significant). On multivariable analyses, ERAS was significantly associated with a reduction in LOS (- 2.89 days, 95% CI - 4.84 to - 0.94) and complication rates (odds ratio 0.22, 95% CI 0.08-0.57). CONCLUSIONS: Implementation of an ERAS program for CRS and HIPEC is associated with a reduction in overall intravenous fluids, postoperative narcotic use, complication rates, and LOS.


Asunto(s)
Procedimientos Quirúrgicos de Citorreducción , Recuperación Mejorada Después de la Cirugía , Hipertermia Inducida , Neoplasias/mortalidad , Neoplasias/terapia , Adulto , Anciano , Analgésicos Opioides/uso terapéutico , Antineoplásicos/uso terapéutico , Terapia Combinada , Femenino , Fluidoterapia/estadística & datos numéricos , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Readmisión del Paciente , Complicaciones Posoperatorias/epidemiología , Tasa de Supervivencia , Resultado del Tratamiento
10.
Nucleic Acids Res ; 46(6): 3152-3168, 2018 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-29309648

RESUMEN

The muscleblind-like (MBNL) family of proteins are key developmental regulators of alternative splicing. Sequestration of MBNL proteins by expanded CUG/CCUG repeat RNA transcripts is a major pathogenic mechanism in the neuromuscular disorder myotonic dystrophy (DM). MBNL1 contains four zinc finger (ZF) motifs that form two tandem RNA binding domains (ZF1-2 and ZF3-4) which each bind YGCY RNA motifs. In an effort to determine the differences in function between these domains, we designed and characterized synthetic MBNL proteins with duplicate ZF1-2 or ZF3-4 domains, referred to as MBNL-AA and MBNL-BB, respectively. Analysis of splicing regulation revealed that MBNL-AA had up to 5-fold increased splicing activity while MBNL-BB had 4-fold decreased activity compared to a MBNL protein with the canonical arrangement of zinc finger domains. RNA binding analysis revealed that the variations in splicing activity are due to differences in RNA binding specificities between the two ZF domains rather than binding affinity. Our findings indicate that ZF1-2 drives splicing regulation via recognition of YGCY RNA motifs while ZF3-4 acts as a general RNA binding domain. Our studies suggest that synthetic MBNL proteins with improved or altered splicing activity have the potential to be used as both tools for investigating splicing regulation and protein therapeutics for DM and other microsatellite diseases.


Asunto(s)
Empalme Alternativo , Ingeniería de Proteínas/métodos , Precursores del ARN/metabolismo , Proteínas de Unión al ARN/metabolismo , ARN/metabolismo , Secuencia de Bases , Sitios de Unión/genética , Células HEK293 , Células HeLa , Humanos , Distrofia Miotónica/genética , Distrofia Miotónica/terapia , Motivos de Nucleótidos/genética , ARN/genética , Precursores del ARN/genética , Motivos de Unión al ARN/genética , Proteínas de Unión al ARN/genética , Dedos de Zinc/genética
11.
Proc Natl Acad Sci U S A ; 114(40): E8537-E8546, 2017 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-28923925

RESUMEN

Seismic surveys map the seabed using intense, low-frequency sound signals that penetrate kilometers into the Earth's crust. Little is known regarding how invertebrates, including economically and ecologically important bivalves, are affected by exposure to seismic signals. In a series of field-based experiments, we investigate the impact of exposure to seismic surveys on scallops, using measurements of physiological and behavioral parameters to determine whether exposure may cause mass mortality or result in other sublethal effects. Exposure to seismic signals was found to significantly increase mortality, particularly over a chronic (months postexposure) time scale, though not beyond naturally occurring rates of mortality. Exposure did not elicit energetically expensive behaviors, but scallops showed significant changes in behavioral patterns during exposure, through a reduction in classic behaviors and demonstration of a nonclassic "flinch" response to air gun signals. Furthermore, scallops showed persistent alterations in recessing reflex behavior following exposure, with the rate of recessing increasing with repeated exposure. Hemolymph (blood analog) physiology showed a compromised capacity for homeostasis and potential immunodeficiency, as a range of hemolymph biochemistry parameters were altered and the density of circulating hemocytes (blood cell analog) was significantly reduced, with effects observed over acute (hours to days) and chronic (months) scales. The size of the air gun had no effect, but repeated exposure intensified responses. We postulate that the observed impacts resulted from high seabed ground accelerations driven by the air gun signal. Given the scope of physiological disruption, we conclude that seismic exposure can harm scallops.


Asunto(s)
Acústica , Conducta Animal , Exposición a Riesgos Ambientales , Ruido , Pecten/fisiología , Sonido , Estrés Fisiológico , Animales
12.
J Emerg Med ; 59(1): 1-11, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32389434

RESUMEN

BACKGROUND: Falls are among the leading cause of emergency department (ED) visits. OBJECTIVE: We set out to determine whether using a bedside decision aid could decrease falls. METHODS: This randomized controlled trial was conducted on those aged ≥ 65 years who were being discharged home and screened positive for a Centers for Disease Control and Prevention (CDC) fall risk factor. Control-arm subjects were given a CDC brochure about falls. The active-arm subjects received a personalized decision aid intervention. Both groups were followed up via telephone. RESULTS: A total of 200 subjects were enrolled and, after exclusions, 184 patients were analyzed. There were 76 male (41.3%) and 108 female (58.7%) subjects; 14% of the subjects chose to have their medications reviewed, 13.6% chose to have an eye examination, 22.8% chose to begin an exercise program, and the majority (44.6%) chose to have a home safety evaluation. Patients in the intervention arm chose more interventions to complete compared to control-arm subjects (p < 0.0001), but did not complete more interventions (p = 0.3387) and did not experience fewer falls compared to the control arm (p = 0.5675). At study conclusion, 73 subjects reported at least one fall during the study. CONCLUSIONS: Overall, in this study, subjects who had their fall-risk interventions facilitated by a decision tool chose to participate in interventions more than control subjects. However, they did not complete the interventions or fall less often than their counterparts in the control arm. Future study is needed to determine the effect of CDC screening guidelines and interventions facilitated by a decision aid on fall outcomes and their application in the ED population.


Asunto(s)
Accidentes por Caídas , Servicio de Urgencia en Hospital , Accidentes por Caídas/prevención & control , Anciano , Ejercicio Físico , Femenino , Humanos , Masculino , Alta del Paciente , Factores de Riesgo
13.
Proc Biol Sci ; 286(1907): 20191424, 2019 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-31337309

RESUMEN

The effects of anthropogenic aquatic noise on marine invertebrates are poorly understood. We investigated the impact of seismic surveys on the righting reflex and statocyst morphology of the palinurid rock lobster, Jasus edwardsii, using field-based exposure to air gun signals. Following exposure equivalent to a full-scale commercial assay passing within 100-500 m, lobsters showed impaired righting and significant damage to the sensory hairs of the statocyst. Reflex impairment and statocyst damage persisted over the course of the experiments-up to 365 days post-exposure and did not improved following moulting. These results indicate that exposure to air gun signals caused morphological damage to the statocyst of rock lobsters, which can in turn impair complex reflexes. This damage and impairment adds further evidence that anthropogenic aquatic noise has the potential to harm invertebrates, necessitating a better understanding of possible ecological and economic impacts.


Asunto(s)
Ruido/efectos adversos , Palinuridae/fisiología , Acústica , Animales , Femenino , Armas de Fuego , Palinuridae/efectos de la radiación , Reflejo de Enderezamiento/fisiología , Reflejo de Enderezamiento/efectos de la radiación , Órganos de los Sentidos/fisiología , Órganos de los Sentidos/efectos de la radiación
14.
J Surg Oncol ; 119(5): 660-666, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30802314

RESUMEN

Enhanced recovery in liver surgery has been shown to improve outcomes including patient-reported outcomes, length of stay, return to intended oncology therapy, and cost. The goal of this chapter will be to review the elements of a modern enhanced recovery pathway that is utilized across the entire episode of care in liver surgery.


Asunto(s)
Neoplasias Colorrectales/patología , Hepatectomía , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Anestesia/métodos , Profilaxis Antibiótica , Fluidoterapia , Humanos , Neoplasias Hepáticas/fisiopatología , Educación del Paciente como Asunto , Cuidados Posoperatorios , Náusea y Vómito Posoperatorios/prevención & control , Cuidados Preoperatorios , Recuperación de la Función , Tromboembolia Venosa/prevención & control
15.
Fish Shellfish Immunol ; 89: 660-671, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30902723

RESUMEN

Lobsters are fished world-wide due to their status as a high value, luxury seafood. A large proportion of the product is sold via live export, with lobsters subject to a range of stressors during holding post-capture. Improving the current understanding of the immune response to these stressors assists in improving efficiency and reducing loss in the chain between capture and consumption. In this study, the immune status of four treatment groups of Southern Rock Lobster (Jasus edwardsii) were studied: controls recently landed from a fishing boat, lobsters displaying advanced shell necrosis, lobsters in an unexplained moribund state and lobsters held in a processing facility for 10 weeks in standard conditions (i.e. high density, fasted). A total of 15 immune parameters and 19 haemolymph biochemical parameters were assayed. Phenoloxidase activity was only sporadically observed in haemocyte lysate and was consistently observed at a low level in the plasma with no difference between treatments for either. Haemocyte lysate prophenoloxidase activity was detected in most individuals, with no differences found between treatments. Prophenoloxidase in the plasma showed the highest level of activity, with the shell necrosis treatment demonstrating an elevated activity level relative to the other three treatments. Cell viability was not affected in any treatment. Lobsters with shell necrosis had a reduced capacity for phagocytosis, a significantly higher total haemocyte count, fewer hyalinocytes and more granulocytes and semigranulocytes. Fasted lobsters showed an opposite shift, with significantly more hyalinocytes compared to the other treatments and very few granulocytes and semigranulocytes. The balance of a range electrolytes, minerals metabolites and enzymes were affected in shell necrosis and fasted treatments, raising them as potential markers for immunocompromised lobsters. Multivariate analysis of all assayed parameters showed that all individuals in the necrosis treatment showed a similar, distinct immune response and that the fasted treatment, along with one control and one moribund individual, showed a separate intermediate response. The remainder of the control and moribund lobsters demonstrated a distinct "non-response" in comparison. These results offer a characterisation of the physiological response to common challenges during post-capture holding of rock lobsters, demonstrating the differential response to pathogenic bacterial infection, long term fasting, non-specific moribundity and the stress of capture and transport.


Asunto(s)
Hemocitos/enzimología , Hemolinfa/química , Inmunidad Innata , Palinuridae/inmunología , Animales , Femenino , Masculino , Estrés Fisiológico
16.
Nature ; 495(7440): 227-30, 2013 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-23434756

RESUMEN

Haematopoietic stem cells (HSCs) primarily reside in the bone marrow where signals generated by stromal cells regulate their self-renewal, proliferation and trafficking. Endosteal osteoblasts and perivascular stromal cells including endothelial cells, CXCL12-abundant reticular cells, leptin-receptor-positive stromal cells, and nestin-green fluorescent protein (GFP)-positive mesenchymal progenitors have all been implicated in HSC maintenance. However, it is unclear whether specific haematopoietic progenitor cell (HPC) subsets reside in distinct niches defined by the surrounding stromal cells and the regulatory molecules they produce. CXCL12 (chemokine (C-X-C motif) ligand 12) regulates both HSCs and lymphoid progenitors and is expressed by all of these stromal cell populations. Here we selectively deleted Cxcl12 from candidate niche stromal cell populations and characterized the effect on HPCs. Deletion of Cxcl12 from mineralizing osteoblasts has no effect on HSCs or lymphoid progenitors. Deletion of Cxcl12 from osterix-expressing stromal cells, which include CXCL12-abundant reticular cells and osteoblasts, results in constitutive HPC mobilization and a loss of B-lymphoid progenitors, but HSC function is normal. Cxcl12 deletion from endothelial cells results in a modest loss of long-term repopulating activity. Strikingly, deletion of Cxcl12 from nestin-negative mesenchymal progenitors using Prx1-cre (Prx1 also known as Prrx1) is associated with a marked loss of HSCs, long-term repopulating activity, HSC quiescence and common lymphoid progenitors. These data suggest that osterix-expressing stromal cells comprise a distinct niche that supports B-lymphoid progenitors and retains HPCs in the bone marrow, and that expression of CXCL12 from stromal cells in the perivascular region, including endothelial cells and mesenchymal progenitors, supports HSCs.


Asunto(s)
Quimiocina CXCL2/metabolismo , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Células Madre Mesenquimatosas/metabolismo , Animales , Linfocitos B/citología , Médula Ósea/metabolismo , Movimiento Celular , Quimiocina CXCL2/deficiencia , Quimiocina CXCL2/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Proteínas de Filamentos Intermediarios/deficiencia , Células Progenitoras Linfoides/citología , Células Progenitoras Linfoides/metabolismo , Células Madre Mesenquimatosas/citología , Ratones , Proteínas del Tejido Nervioso/deficiencia , Nestina , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Nicho de Células Madre/fisiología
17.
Blood ; 125(20): 3114-7, 2015 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-25814527

RESUMEN

The mechanisms that mediate the shift from lymphopoiesis to myelopoiesis in response to infectious stress are largely unknown. We show that treatment with granulocyte colony-stimulating factor (G-CSF), which is often induced during infection, results in marked suppression of B lymphopoiesis at multiple stages of B-cell development. Mesenchymal-lineage stromal cells in the bone marrow, including CXCL12-abundant reticular (CAR) cells and osteoblasts, constitutively support B lymphopoiesis through the production of multiple B trophic factors. G-CSF acting through a monocytic cell intermediate reprograms these stromal cells, altering their capacity to support B lymphopoiesis. G-CSF treatment is associated with an expansion of CAR cells and a shift toward osteogenic lineage commitment. It markedly suppresses the production of multiple B-cell trophic factors by CAR cells and osteoblasts, including CXCL12, kit ligand, interleukin-6, interleukin-7, and insulin-like growth factor-1. Targeting bone marrow stromal cells is one mechanism by which inflammatory cytokines such as G-CSF actively suppress lymphopoiesis.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos/farmacología , Linfopoyesis/efectos de los fármacos , Linfopoyesis/fisiología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Animales , Linfocitos B/citología , Linfocitos B/metabolismo , Linaje de la Célula/efectos de los fármacos , Quimiocina CXCL12/metabolismo , Inmunofenotipificación , Ratones , Ratones Transgénicos , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo
18.
J Emerg Med ; 53(3): 339-344, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28755998

RESUMEN

BACKGROUND: Loperamide is an over-the-counter, inexpensive, antidiarrheal opioid that can produce life-threatening toxicity at high concentrations. CASE REPORT 1: A 28-year-old man with a history of depression and substance abuse disorder (SUD) presented to the emergency department (ED) with shortness of breath and lightheadedness. He ingested large amounts of loperamide daily. The patient's initial electrocardiogram (ECG) demonstrated sinus rhythm, right axis deviation, undetectable PR interval, QRS 168 ms, and QTc 693 ms. He was administered intravenous sodium bicarbonate and magnesium sulfate and admitted to the intensive care unit, eventually developing Torsades de Pointes (TdP). He was given lidocaine and isoproterenol infusions, and an external pacemaker was placed. He was discharged in stable condition on hospital day (HD) 16. CASE REPORT 2: A 39-year-old woman with a history of hepatitis C, depression, and SUD was transported to the ED after reported seizure-like activity. The patient experienced TdP in the ED and admitted to ingesting large amount of loperamide daily. An ECG demonstrated sinus rhythm, right axis deviation, PR interval 208 ms, QRS interval 142 ms, and QTc 687 ms. She was administered intravenous magnesium, sodium bicarbonate, and isoproterenol. After intensive care unit admission, the patient experienced no further TdP and was discharged on HD 6. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians should proceed with caution when treating patients with loperamide toxicity. Even in asymptomatic patients and drug discontinuance, obtain consultation with a medical toxicologist, promptly treat ECG abnormalities aggressively, and admit all patients for further monitoring.


Asunto(s)
Antidiarreicos/envenenamiento , Sobredosis de Droga/complicaciones , Loperamida/envenenamiento , Torsades de Pointes/inducido químicamente , Adulto , Femenino , Humanos , Masculino
20.
J Surg Res ; 200(1): 46-52, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26276369

RESUMEN

BACKGROUND: Although simulation training and evaluation have become increasingly popular for teaching minimally invasive surgery, tools to measure open surgical skills remain underdeveloped. As there is increasing demand for objective measures of technical competency at the completion of surgical training (postgraduate year [PGY]-6 and -7), this project was designed to assess the feasibility, reliability, and validity of a novel open surgical skills evaluation tool, the 8-min suture test (8MST). METHODS: During an annual surgical skills laboratory session, fellows and residents were asked to complete a simulated end-to-end vascular anastomosis. They were limited to 8 min to perform the anastomosis between two 12-mm Dacron grafts mounted on a customized platform. Their real-time and video-recorded performance was scored by two blinded evaluators and compared with their faculty-rated technical performance on clinical rotations completed around the time of 8MST administration. RESULTS: PGY-6 and PGY-7 trainees were compared across several domains including 8MST total score (4.6 versus 5.5, P = 0.030), 8MST setup score (2.3 versus 2.4, P = 0.797), 8MST technical score (2.3 versus 3.1, P = 0.026), and clinical performance score (3.1 versus 3.6, P = 0.006). Comparison of 8MST total score to the clinical performance score identified a strong relationship with a Pearson r = 0.55 (P < 0.001) and r(2) = 0.30. Additionally, 8MST displayed high inter-rater reliability and test-retest reliability. CONCLUSIONS: The 8MST is a rapid, feasible, inexpensive, reliable, and valid test for assessment of surgical trainee technical abilities.


Asunto(s)
Competencia Clínica , Educación de Postgrado en Medicina , Cirugía General/educación , Internado y Residencia , Técnicas de Sutura/educación , Implantación de Prótesis Vascular/educación , Estudios de Factibilidad , Humanos , Reproducibilidad de los Resultados , Método Simple Ciego , Texas
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