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BACKGROUND AND PURPOSE: Quantitative ultrasound (QUS) performed at the distal radius shows potential as an effective tool for evaluating fracture risk, especially in postmenopausal women, but the reliability of this tool has not been reported in this patient population. This study investigated the within-day intrarater and interrater reliability of trained raters performing QUS measures at the distal radius of postmenopausal community-dwelling women. METHODS: Eighteen women between the ages of 56 and 87 years were recruited from senior centers in the Greenville area of South Carolina and consented to participate. A QUS bone sonometer was used in this study; the trained raters performed 3 repeated speed of sound (SOS) measures at the nondominant radius of each participant on the same day. Intraclass correlation coefficients (ICCs) were calculated (model 3,1 for intrarater and 2,3 for interrater reliability) to determine the reliability within and between raters. In addition, we calculated the standard error of measurement (SEM) and the minimal detectable change at 95% confidence interval (MDC95). RESULTS: The within-day intrarater reliability was excellent for both physical therapist raters (ICC(3,1) ranging from 0.93 to 0.91). The SEM and MDC for the within-day intrarater reliability measures were small for both raters (SEM = 36.79-38.75 or 0.92%-0.97% of the pooled mean; MDC95 = 101.99-107.40). The interrater reliability for SOS measurements using radial QUS was good with an ICC(2,3) of 0.77 (95% CI, 0.36-0.92) for 3 averaged measures. The SEM and MDC were larger for the interrater reliability measures (SEM = 62.79 or 1.57% of the pooled mean; MDC95 = 174.05). CONCLUSIONS: Quantitative ultrasound SOS measurement at the distal radius showed excellent within-day intrarater and good interrater (when 3 measures were averaged) reliability in community-dwelling postmenopausal women. The SEM and MDC95 were also low for interrater reliability when a mean of 3 trials was used. This study is the first to demonstrate that this particular QUS device at the radius may be a reliable fracture risk screening tool for postmenopausal women.
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WRN helicase is a promising target for treatment of cancers with microsatellite instability (MSI) due to its essential role in resolving deleterious non-canonical DNA structures that accumulate in cells with faulty mismatch repair mechanisms1-5. Currently there are no approved drugs directly targeting human DNA or RNA helicases, in part owing to the challenging nature of developing potent and selective compounds to this class of proteins. Here we describe the chemoproteomics-enabled discovery of a clinical-stage, covalent allosteric inhibitor of WRN, VVD-133214. This compound selectively engages a cysteine (C727) located in a region of the helicase domain subject to interdomain movement during DNA unwinding. VVD-133214 binds WRN protein cooperatively with nucleotide and stabilizes compact conformations lacking the dynamic flexibility necessary for proper helicase function, resulting in widespread double-stranded DNA breaks, nuclear swelling and cell death in MSI-high (MSI-H), but not in microsatellite-stable, cells. The compound was well tolerated in mice and led to robust tumour regression in multiple MSI-H colorectal cancer cell lines and patient-derived xenograft models. Our work shows an allosteric approach for inhibition of WRN function that circumvents competition from an endogenous ATP cofactor in cancer cells, and designates VVD-133214 as a promising drug candidate for patients with MSI-H cancers.
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Regulación Alostérica , Descubrimiento de Drogas , Inhibidores Enzimáticos , Proteómica , Helicasa del Síndrome de Werner , Animales , Femenino , Humanos , Masculino , Ratones , Regulación Alostérica/efectos de los fármacos , Línea Celular Tumoral , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/enzimología , Neoplasias Colorrectales/patología , Cisteína/efectos de los fármacos , Cisteína/metabolismo , Roturas del ADN de Doble Cadena/efectos de los fármacos , Descubrimiento de Drogas/métodos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Inestabilidad de Microsatélites , Modelos Moleculares , Helicasa del Síndrome de Werner/antagonistas & inhibidores , Helicasa del Síndrome de Werner/química , Helicasa del Síndrome de Werner/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Muerte Celular/efectos de los fármacos , Adenosina Trifosfato/metabolismoRESUMEN
INTRODUCTION: Image-guided renal mass biopsy is gaining increased diagnostic acceptance, but there are limited data concerning the safety and diagnostic yield of biopsy for small renal masses (≤4 cm). This study evaluated the safety, diagnostic yield, and management after image-guided percutaneous biopsy for small renal masses. METHODS: A retrospective IRB-approved study was conducted on patients who underwent renal mass biopsy for histopathologic diagnosis at a single center from 2015 to 2021. Patients with a prior history of malignancy or a renal mass >4 cm were excluded. Descriptive statistics were used to summarize patient demographics, tumor size, the imaging modality used for biopsy, procedure details, complications, pathological diagnosis, and post-biopsy management. A biopsy was considered successful when the specimen was sufficient for diagnosis without need for a repeat biopsy. Complications were graded according to the SIR classification of adverse events. A chi-squared test (significance level set at p ≤ 0.05) was used to compare the success rate of biopsies in different lesion size groups. RESULTS: A total of 167 patients met the inclusion criteria. The median age was 65 years (range: 26-87) and 51% were male. The median renal mass size was 2.6 cm (range: one-four). Ultrasound was solely employed in 60% of procedures, CT in 33%, a combination of US/CT in 6%, and MRI in one case. With on-site cytopathology, the median number of specimens obtained per procedure was four (range: one-nine). The overall complication rate was 5%. Grade A complications were seen in 4% (n = 7), consisting of perinephric hematoma (n = 6) and retroperitoneal hematoma (n = 1). There was one grade B complication (0.5%; pain) and one grade D complication (0.5%; pyelonephritis). There was no patient mortality within 30 days post-biopsy. Biopsy was successful in 88% of cases. A sub-group analysis showed a success rate of 85% in tumors <3 cm and 93% in tumors ≥3 cm (p = 0.01). Pathological diagnoses included renal cell carcinoma (65%), oncocytoma (18%), clear cell papillary renal cell tumors (9%), angiomyolipoma (4%), xanthogranulomatous pyelonephritis (1%), lymphoma (1%), high-grade papillary urothelial carcinoma (1%), and metanephric adenoma (1%), revealing benign diagnosis in 30% of cases. The most common treatment was surgery (40%), followed by percutaneous cryoablation (22%). In total, 37% of patients were managed conservatively, and one patient received chemotherapy. CONCLUSION: This study demonstrates the safety and diagnostic efficacy of image-guided biopsy of small renal masses. The diagnostic yield was significantly higher for masses 3-4 cm in size compared to those <3 cm. The biopsy results showed a high percentage of benign diagnoses and informed treatment decisions in most patients.
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The gold-standard treatment of acute calculous cholecystitis is cholecystectomy. For patients not suitable for surgery, endoscopic or percutaneous techniques can be used for gallbladder decompression. The national percutaneous cholecystostomy rates have increased by 567% from 1994 to 2009*. Some of these patients are still not surgical candidates after the acute cholecystitis episode has resolved. Hence, it is crucial to have a management plan in place for such patients. There are several peroral endoscopic treatment options available, including ultrasound-guided transmural drainage, lithotripsy, and transpapillary stenting**. Furthermore, due to the advent of percutaneous biliary endoscopes, interventional radiology (IR) can now perform percutaneous lithotripsy and gallstone removal followed by cystic duct stenting. This method aims to internalize gallbladder drainage without the need for a long-term external cholecystostomy tube. Acute pancreatitis is a rare complication that can arise following interventions involving the biliary and cystic ducts. Acute pancreatitis can occur after retrograde ampullary manipulation during endoscopic retrograde cholangiopancreatography. However, this can sometimes happen after percutaneous antegrade interventions performed by IR. In this report, we will examine a rare complication that occurred in a patient with acute calculous cholecystitis: acute pancreatitis following percutaneous electrohydraulic lithotripsy with cystic duct stenting performed by IR.
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Purpose: This biomechanical study evaluated the effect of intramedullary screw diameter and length relative to 3-point bending force and torsional force when used to stabilize metacarpal shaft fractures. Methods: Transverse osteotomies were made in the proximal metacarpal shaft in 36 middle finger metacarpal fourth-generation composite Sawbones. To compare screw diameters, antegrade intramedullary screws of 30-mm length were placed in 6 metacarpals, which included 4.7-mm Acutrak 2, Standard Acutrak 2 (4.0 mm), and Mini-Acutrak 2 (3.5 mm) screws. To compare screw lengths, metacarpals were fixated with Standard Acutrak 2 screws of 26, 30, or 34 mm in length, with screw tips bypassing the osteotomy by 6, 10, or 14 mm, respectively. A 6 degrees of freedom robot was used for torsional and 3-point bending testing. Results: Increasing screw diameter demonstrated significant differences in both 3-point bending and torsional strengths. Maximum torsional loads were 69 Ncm (4.7-mm Acutrak 2), 45 Ncm (Standard Acutrak 2), and 27 Ncm (Mini-Acutrak 2) (P < .05). Loads to failure in the 3-point bending tests were 916 N (4.7-mm Acutrak 2), 713 N (Standard Acutrak 2), and 284 N (Mini-Acutrak 2) (P < .05). Differing screw lengths demonstrated significant differences with maximum torsional loads when comparing the 26-mm screws (22 Ncm) with 30- and 34-mm screws (45 and 55 Ncm, respectively) (P < .05). The 3-point dorsal bending strengths were significantly different between the 26-mm screws (320 N) and 30- and 34-mm screws (713 N and 702 N, respectively) (P < .05). Conclusions: The results demonstrated significantly higher torsional strength and resistance to 3-point bending with larger intramedullary screw diameters. Further, when selecting the intramedullary screw length, the screw tip should pass at least 10 mm beyond the fracture. Clinical Relevance: This study provided biomechanical evidence to guide surgeons in selecting intramedullary screw diameter and length for treating metacarpal fractures.
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PURPOSE: To evaluate the safety and efficacy of yttrium-90 (90Y) radiation segmentectomy (RS) in the treatment of oligometastatic secondary hepatic malignancies. MATERIALS AND METHODS: This institutional review board-approved retrospective study evaluated 16 patients with oligometastatic secondary hepatic malignancies who were treated with RS. The median patient age was 61.9 years (range, 38.6-85.7 years). Of the 16 patients, 11 (68.8%) presented with solitary lesions. The median index tumor size was 3.1 cm (95% CI, 2.3-3.9). Primary outcomes were evaluation of clinical and biochemical toxicities using National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0, and imaging response using Response Evaluation Criteria in Solid Tumors, version 1.1. Secondary outcomes were time to progression (TTP) and overall survival (OS) as estimated by the Kaplan-Meier method. RESULTS: Clinical Grade 3 toxicities were limited to 1 (6.7%) patient who experienced fatigue, abdominal pain, nausea, and vomiting. Biochemical Grade 3 toxicities occurred in 1 (6.7%) patient who experienced lymphopenia. No Grade 4 clinical or biochemical toxicities were identified. Disease control was achieved in 14 (93.3%) of 15 patients. The median TTP of the treated tumor was 72.9 months (95% CI, 11.2 to no estimate). The median OS was 60.9 months (95% CI, 24.7 to no estimate). CONCLUSIONS: 90Y RS displayed an excellent safety profile and was effective in achieving a high disease control rate in the treatment of oligometastatic secondary hepatic malignancies.
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Neoplasias Hepáticas , Neumonectomía , Humanos , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Resultado del Tratamiento , Estudios Retrospectivos , Neoplasias Hepáticas/patología , Radioisótopos de Itrio/efectos adversosRESUMEN
Rarely, immunophenotypically immature B-cell precursor acute lymphoblastic leukemia (BCP-ALL) carries an immunoglobulin- MYC rearrangement (IG-MYC-r). This can result in diagnostic confusion with Burkitt lymphoma/leukemia and use of individualized treatment schedules of unproven efficacy. Here we compare the molecular characteristics of these conditions and investigate historic clinical outcome data. We identified 90 cases registered in a national BCP-ALL clinical trial/registry. When present, diagnostic material underwent cytogenetic, exome, methylome and transcriptome analyses. The outcomes analyzed were 3-year event-free survival and overall survival. IG-MYC-r was identified in diverse cytogenetic backgrounds, co-existing with either established BCP-ALL-specific abnormalities (high hyperdiploidy, n=3; KMT2A-rearrangement, n=6; iAMP21, n=1; BCR-ABL1, n=1); BCL2/BCL6-rearrangements (n=15); or, most commonly, as the only defining feature (n=64). Within this final group, precursor-like V(D)J breakpoints predominated (8/9) and KRAS mutations were common (5/11). DNA methylation identified a cluster of V(D)J-rearranged cases, clearly distinct from Burkitt leukemia/lymphoma. Children with IG-MYC-r within that subgroup had a 3-year event-free survival of 47% and overall survival of 60%, representing a high-risk BCP-ALL. To develop effective management strategies this group of patients must be allowed access to contemporary, minimal residual disease-adapted, prospective clinical trial protocols.
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Linfoma de Burkitt , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Niño , Humanos , Linfoma de Burkitt/diagnóstico , Linfoma de Burkitt/genética , Linfoma de Burkitt/terapia , Estudios Prospectivos , Inmunoglobulinas/genética , Reordenamiento Génico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapiaRESUMEN
BACKGROUND: A 10-hospital regional network transitioned to tenecteplase as the standard of care stroke thrombolytic in September 2019 because of potential workflow advantages and reported noninferior clinical outcomes relative to alteplase in meta-analyses of randomized trials. We assessed whether tenecteplase use in routine clinical practice reduced thrombolytic workflow times with noninferior clinical outcomes. METHODS: We designed a prospective registry-based observational, sequential cohort comparison of tenecteplase- (n=234) to alteplase-treated (n=354) stroke patients. We hypothesized: (1) an increase in the proportion of patients meeting target times for target door-to-needle time and transfer door-in-door-out time, and (2) noninferior favorable (discharge to home with independent ambulation) and unfavorable (symptomatic intracranial hemorrhage, in-hospital mortality or discharge to hospice) in the tenecteplase group. Total hospital cost associated with each treatment was also compared. RESULTS: Target door-to-needle time within 45 minutes for all patients was superior for tenecteplase, 41% versus 29%; adjusted odds ratio, 1.85 (95% CI, 1.27-2.71); P=0.001; 58% versus 41% by Get With The Guidelines criteria. Target door-in-door-out time within 90 minutes was superior for tenecteplase 37% (15/43) versus 14% (9/65); adjusted odds ratio, 3.62 (95% CI, 1.30-10.74); P=0.02. Favorable outcome for tenecteplase fell within the 6.5% noninferiority margin; adjusted odds ratio, 1.26 (95% CI, 0.89-1.80). Unfavorable outcome was less for tenecteplase, 7.3% versus 11.9%, adjusted odds ratio, 0.77 (95% CI, 0.42-1.37) but did not fall within the prespecified 1% noninferior boundary. Net benefit (%favorable-%unfavorable) was greater for the tenecteplase sample: 37% versus 27%. P=0.02. Median cost per hospital encounter was less for tenecteplase cases ($13 382 versus $15 841; P<0.001). CONCLUSIONS: Switching to tenecteplase in routine clinical practice in a 10-hospital network was associated with shorter door-to-needle time and door-in-door-out times, noninferior favorable clinical outcomes at discharge, and reduced hospital costs. Evaluation in larger, multicenter cohorts is recommended to determine if these observations generalize.
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Isquemia Encefálica , Accidente Cerebrovascular , Humanos , Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Tenecteplasa/uso terapéutico , Activador de Tejido Plasminógeno/uso terapéutico , Resultado del TratamientoRESUMEN
PURPOSE: Unresectable intrahepatic cholangiocarcinoma (ICC) signifies a poor prognosis with limited treatment options beyond systemic chemotherapy. This study's purpose was to evaluate the safety, efficacy, and potential for downstaging to resection of yttrium-90 (Y90) radioembolization for treatment of unresectable ICC. MATERIALS AND METHODS: From 2004 to 2020, 136 patients with unresectable ICC were treated with radioembolization at a single institution. Retrospective review was performed of a prospectively collected database. Outcomes were (1) biochemical and clinical toxicities, (2) local tumor response, (3) time to progression, and (4) overall survival (OS) after Y90. Univariate/multivariate survival analyses were performed. A subgroup analysis was performed to calculate post-resection recurrence and OS in patients downstaged to resection after Y90. RESULTS: Grade 3+ clinical and biochemical toxicities were 7.6% (n = 10) and 4.9% (n = 6), respectively. Best index lesion response was complete response in 2 (1.5%), partial response in 42 (32.1%), stable disease in 82 (62.6%), and progressive disease in 5 (3.8%) patients. Median OS was 14.2 months. Solitary tumor (P < 0.001), absence of vascular involvement (P = 0.009), and higher serum albumin (P < 0.001) were independently associated with improved OS. Eleven patients (8.1%) were downstaged to resection and 2 patients (1.5%) were bridged to transplant. R0-resection was achieved in 8/11 (72.7%). Post-resection median recurrence and OS were 26.3 months and 39.9 months, respectively. CONCLUSION: Y90 has an acceptable safety profile and high local disease control rates for the treatment of unresectable ICC. Downstaging to resection with > 3 years survival supports the therapeutic role of Y90 for unresectable ICC. LEVEL OF EVIDENCE: Level 3, single-arm single-center cohort study.
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Neoplasias de los Conductos Biliares , Colangiocarcinoma , Embolización Terapéutica , Neoplasias Hepáticas , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología , Colangiocarcinoma/cirugía , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/terapia , Estudios Retrospectivos , Resultado del Tratamiento , Radioisótopos de Itrio/uso terapéuticoRESUMEN
CX5461, a compound initially identified as an RNA polymerase inhibitor and more recently as a G-quadruplex binder, binds copper to form a complex. Our previous publication showed that the complexation reaction can be leveraged to formulate copper-CX5461 inside liposomes, improving the apparent solubility of CX5461 by over 500-fold and reducing the elimination of CX5461 from the plasma compartment following intravenous administration. In mouse models of acute myeloid leukemia, the resulting formulation was more effective than the free drug solution of CX5461 (pH 3.5) currently used in clinical trials. However, the gains observed with the liposomal formulation were minimal, despite significant increases in circulation half-life. Since the formulation technology used relied on liposomes and the fate of most compounds associated with liposomes is dependent on liposomal lipid composition, the studies described here were designed to evaluate how simple changes in lipid composition could affect therapeutic activity. The previously reported formulation method was simplified to ensure an easy scale-up process. In the modified method, pre-measured solid CX5461 was added to copper-containing liposomes prior to an incubation at 60 °C, which enabled copper-CX5461 complexation inside DSPC/Chol or DMPC/Chol liposomes. Efficacy was determined in BRCA-normal (BxPC3) and BRCA-deficient (Capan-1) models of pancreatic cancer. Both liposomal formulations enhanced the circulation lifetime of CX5461 compared to the free drug solution (pH 3.5). Unlike most compounds that are loaded using a transmembrane pH-gradient, the dissociation of CX5461 from liposomes prepared using the copper complexation method were comparable for DSPC/Chol and DMPC/Chol liposomes, in vitro and in vivo. Nonetheless, copper CX5461 prepared using DMPC/Chol liposomes exhibited superior efficacy. The reason for the improved activity of DMPC/Chol copper-CX5461 was not readily explained by the release data and may be due to the fact that DMPC/Chol liposomes are less stable following localization in the tumor. The results indicate that the therapeutic effects of copper-CX5461 will be dependent on liposomal lipid composition and that liposomal CX5461 should exhibit superior benefits when used to treat BRCA-deficient cancers.
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Leucemia Mieloide Aguda , Liposomas , Animales , Benzotiazoles , Cobre/química , Dimiristoilfosfatidilcolina/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Liposomas/química , Ratones , NaftiridinasRESUMEN
B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is a malignancy of dysregulated lymphocytes in bone marrow and lymphatics. Extra-nodal involvement has been previously cited to affect areas like the lungs, skin, central nervous system, and kidney. Gastrointestinal (GI) involvement in patients with chronic CLL/SLL is rare. We report a unique case of CLL/SLL found incidentally in a 71-year-old asymptomatic female undergoing a screening colonoscopy. Patients with GI infiltration of CLL/SLL may be asymptomatic like the patient described in this report, or present with symptoms that may resemble inflammatory bowel disease, microscopic colitis, or colon cancer. Therefore, it is important to remain vigilant for the occurrence of other malignancies during the follow-up of CLL/SLL patients.
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Lignin, the second most abundant biopolymer, is a promising renewable energy source and chemical feedstock. A key element of lignin biosynthesis is unknown: how do lignin precursors (monolignols) get from inside the cell out to the cell wall where they are polymerized? Modeling indicates that monolignols can passively diffuse through lipid bilayers, but this has not been tested experimentally. We demonstrate significant monolignol diffusion occurs when laccases, which consume monolignols, are present on one side of the membrane. We hypothesize that lignin polymerization could deplete monomers in the wall, creating a concentration gradient driving monolignol diffusion. We developed a two-photon microscopy approach to visualize lignifying Arabidopsis thaliana root cells. Laccase mutants with reduced ability to form lignin polymer in the wall accumulated monolignols inside cells. In contrast, active transport inhibitors did not decrease lignin in the wall and scant intracellular phenolics were observed. Synthetic liposomes were engineered to encapsulate laccases, and monolignols crossed these pure lipid bilayers to form polymer within. A sink-driven diffusion mechanism explains why it has been difficult to identify genes encoding monolignol transporters and why the export of varied phenylpropanoids occurs without specificity. It also highlights an important role for cell wall oxidative enzymes in monolignol export.
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Arabidopsis , Lignina , Arabidopsis/genética , Arabidopsis/metabolismo , Pared Celular/metabolismo , Lacasa/genética , Lacasa/metabolismo , Lignina/metabolismo , Membrana Dobles de Lípidos/metabolismo , PolimerizacionRESUMEN
Chromosomal translocations are important drivers of haematological malignancies whereby proto-oncogenes are activated by juxtaposition with enhancers, often called enhancer hijacking We analyzed the epigenomic consequences of rearrangements between the super-enhancers of the immunoglobulin heavy locus (IGH) and proto-oncogene CCND1 that are common in B cell malignancies. By integrating BLUEPRINT epigenomic data with DNA breakpoint detection, we characterized the normal chromatin landscape of the human IGH locus and its dynamics after pathological genomic rearrangement. We detected an H3K4me3 broad domain (BD) within the IGH locus of healthy B cells that was absent in samples with IGH-CCND1 translocations. The appearance of H3K4me3-BD over CCND1 in the latter was associated with overexpression and extensive chromatin accessibility of its gene body. We observed similar cancer-specific H3K4me3-BDs associated with hijacking of super-enhancers of other common oncogenes in B cell (MAF, MYC, and FGFR3/NSD2) and T cell malignancies (LMO2, TLX3, and TAL1). Our analysis suggests that H3K4me3-BDs can be created by super-enhancers and supports the new concept of epigenomic translocation, in which the relocation of H3K4me3-BDs from cell identity genes to oncogenes accompanies the translocation of super-enhancers.
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Epigenómica , Translocación Genética , Cromatina/genética , Histonas , Humanos , OncogenesRESUMEN
For more than 30 years, treatment of acute myeloid leukemia (AML) has remained largely unchanged and reliant on chemotherapeutic drug combinations, specifically cytarabine and daunorubicin (the 7 + 3 regimen). One broad spectrum drug, flavopiridol (also known as Alvocidib) has shown significant activity against AML through the inhibition of cyclin-dependent kinases. Flavopiridol is a semisynthetic flavonoid and our research team recently described methods to formulate another flavonoid, quercetin, through the ability of flavonoids to bind divalent metals. This method relies on use of copper-containing liposomes to enhance the apparent solubility of flavopiridol and to create formulations suitable for intravenous (i.v.) use. Similar to quercetin, flavopiridol is defined as an aqueous-insoluble compound (< 1 mg/mL in water) and this research sought to evaluate whether the copper-binding capabilities of flavopiridol could be used to prepare an injectable formulation that would exhibit enhanced exposure and improved efficacy. Flavopiridol powder was added directly to preformed copper-containing liposomes (DSPC:Chol or DSPC:DSPE-PEG2000) and the resulting formulations were characterized. Pharmacokinetic and efficacy studies were then conducted. The liposomal flavopiridol formulations were well-tolerated in mice following i.v. administration at a dose of 5 mg/kg with no apparent acute or chronic toxicities. In vivo pharmacokinetics of the optimized DSPC/DSPE-PEG2000 liposomal flavopiridol formulation demonstrated a 30-fold increase in AUC (0.804 µg-hr/mL versus 26.92 µg-hr/mL) compared to the free flavopiridol formulation. The resultant liposomal formulation also demonstrated significant therapeutic activity in MV4-11 and MOLM-13 subcutaneous AML models. Additional studies will be required to define whether formulation changes can be made to enhance flavopiridol retention in the selected composition. The results suggest that further increases in flavopiridol retention will result in improved therapeutic activity.
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Leucemia Mieloide Aguda , Animales , Citarabina , Flavonoides , Leucemia Mieloide Aguda/tratamiento farmacológico , Liposomas , Ratones , PiperidinasRESUMEN
Ligand-induced protein degradation has emerged as a compelling approach to promote the targeted elimination of proteins from cells by directing these proteins to the ubiquitin-proteasome machinery. So far, only a limited number of E3 ligases have been found to support ligand-induced protein degradation, reflecting a dearth of E3-binding compounds for proteolysis-targeting chimera (PROTAC) design. Here, we describe a functional screening strategy performed with a focused library of candidate electrophilic PROTACs to discover bifunctional compounds that degrade proteins in human cells by covalently engaging E3 ligases. Mechanistic studies revealed that the electrophilic PROTACs act through modifying specific cysteines in DCAF11, a poorly characterized E3 ligase substrate adaptor. We further show that DCAF11-directed electrophilic PROTACs can degrade multiple endogenous proteins, including FBKP12 and the androgen receptor, in human prostate cancer cells. Our findings designate DCAF11 as an E3 ligase capable of supporting ligand-induced protein degradation via electrophilic PROTACs.
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Complejos de Ubiquitina-Proteína Ligasa/fisiología , Línea Celular Tumoral , Humanos , Masculino , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Receptores Androgénicos/metabolismo , Ubiquitina/metabolismo , Complejos de Ubiquitina-Proteína Ligasa/metabolismoRESUMEN
Ring avulsion injuries are an uncommon, often catastrophic, pattern of digit injuries that result from sudden traction onto a ring-bearing digit. The reconstructive treatment of these injuries can be complex because of the characteristic involvement of nerves, muscles, vasculature, and bone. There is paucity of literature describing isolated arterial injuries in the absence of overlying soft tissue and underlying bone involvement. We present an unusual case of a closed ring avulsion injury, wherein a patient initially presented to his local urgent care center with a cool and pale digit without wounds or fractures, and abnormal pulse oximetry readings prompted his transfer to a tertiary care center for further evaluation. Surgical exploration demonstrated isolated disruption of both digital arteries and the preservation of both digital nerves. The digit was successfully revascularized with venous autografting and stripping of arterial thrombi.
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PURPOSE: To demonstrate a stronger correlation and agreement of yttrium-90 (90Y) positron emission tomography (PET)/computed tomography (CT) measurements with explant liver tumor dosing compared with the standard model (SM) for radioembolization. MATERIALS AND METHODS: Hepatic VX2 tumors were implanted into New Zealand white rabbits, with growth confirmed by 7 T magnetic resonance imaging. Seventeen VX2 rabbits provided 33 analyzed tumors. Treatment volumes were calculated from manually drawn volumes of interest (VOI) with three-dimensional surface renderings. Radioembolization was performed with glass 90Y microspheres. PET/CT imaging was completed with scatter and attenuation correction. Three-dimensional ellipsoid VOI were drawn to encompass tumors on fused images. Tumors and livers were then explanted for inductively coupled plasma (ICP)-optical emission spectroscopy (OES) analysis of microsphere content. 90Y PET/CT and SM measurements were compared with reference standard ICP-OES measurements of tumor dosing with Pearson correlation and Bland-Altman analyses for agreement testing with and without adjustment for tumor necrosis. RESULTS: The median infused activity was 33.3 MBq (range, 5.9-152.9). Tumor dose was significantly correlated with 90Y PET/CT measurements (r = 0.903, P < .001) and SM estimates (r = 0.607, P < .001). Bland-Altman analyses showed that the SM tended to underestimate the tumor dosing by a mean of -8.5 Gy (CI, -26.3-9.3), and the degree of underestimation increased to a mean of -18.3 Gy (CI, -38.5-1.9) after the adjustment for tumor necrosis. CONCLUSIONS: 90Y PET/CT estimates were strongly correlated and had better agreement with reference measurements of tumor dosing than SM estimates.
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Embolización Terapéutica , Neoplasias Hepáticas Experimentales/diagnóstico por imagen , Neoplasias Hepáticas Experimentales/radioterapia , Tomografía Computarizada por Tomografía de Emisión de Positrones , Dosis de Radiación , Radiofármacos/administración & dosificación , Radioisótopos de Itrio/administración & dosificación , Animales , Femenino , Necrosis , Valor Predictivo de las Pruebas , Conejos , Interpretación de Imagen Radiográfica Asistida por Computador , Carga TumoralAsunto(s)
Infecciones por Coronavirus , Pandemias , Neumonía Viral , Betacoronavirus , COVID-19 , Becas , Humanos , SARS-CoV-2RESUMEN
BACKGROUND AND PURPOSE: Blood pressure (BP) variability has been associated with worse neurological outcomes in acute ischaemic stroke (AIS) patients receiving treatment with intravenous thrombolysis (IVT). However, no study to date has investigated whether pulse pressure (PP) variability may be a superior indicator of the total cardiovascular risk, as measured by clinical outcomes. METHODS: Pulse pressure variability was calculated from 24-h PP measurements following tissue plasminogen activator bolus in AIS patients enrolled in the Combined Lysis of Thrombus using Ultrasound and Systemic Tissue Plasminogen Activator for Emergent Revascularization (CLOTBUST-ER) trial. The outcomes of interest were the pre-specified efficacy and safety end-points of CLOTBUST-ER. All associations were adjusted for potential confounders in multivariable regression models. RESULTS: Data from 674 participants was analyzed. PP variability was identified as the BP parameter with the most parsimonious fit in multivariable models of all outcomes, and was independently associated (P < 0.001) with lower likelihood of both 24-h neurological improvement and 90-day independent functional outcome. PP variability was also independently related to increased odds of any intracranial bleeding (P = 0.011) and 90-day mortality (P < 0.001). Every 5-mmHg increase in the 24-h PP variability was independently associated with a 36% decrease in the likelihood of 90-day independent functional outcome (adjusted odds ratio 0.64, 95% confidence interval 0.52-0.80) and a 60% increase in the odds of 90-day mortality (adjusted odds ratio 1.60, 95% confidence interval 1.23-2.07). PP variability was not associated with symptomatic intracranial bleeding at either 24 or 36 h after IVT administration. CONCLUSIONS: Increased PP variability appears to be independently associated with adverse short-term and long-term functional outcomes of AIS patients treated with IVT.