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1.
bioRxiv ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38798402

RESUMO

Because most DNA-binding transcription factors (dbTFs), including the architectural regulator CTCF, bind RNA and exhibit di-/multimerization, a central conundrum is whether these distinct properties are regulated post-transcriptionally to modulate transcriptional programs. Here, investigating stress-dependent activation of SIRT1, encoding an evolutionarily-conserved protein deacetylase, we show that induced phosphorylation of CTCF acts as a rheostat to permit CTCF occupancy of low-affinity promoter DNA sites to precisely the levels necessary. This CTCF recruitment to the SIRT1 promoter is eliciting a cardioprotective cardiomyocyte transcriptional activation program and provides resilience against the stress of the beating heart in vivo . Mice harboring a mutation in the conserved low-affinity CTCF promoter binding site exhibit an altered, cardiomyocyte-specific transcriptional program and a systolic heart failure phenotype. This transcriptional role for CTCF reveals that a covalent dbTF modification regulating signal-dependent transcription serves as a previously unsuspected component of the oxidative stress response.

2.
J Cancer Res Ther ; 20(1): 79-84, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554302

RESUMO

BACKGROUND: Ewing's sarcoma (EWS) is an aggressive small round cell tumor, affecting bone and soft tissues and is mostly seen in childhood and second decade of life. EWS accounts for 10-12% of bone tumors in more than 15 years age group and is even rarer after 40 years of age. MATERIALS AND METHODS: This retrospective analysis was conducted among patients aged more than 15 years with histologically proven EWS. RESULTS: Among 240 cases of EWS treated at our center during 2001-2010, 130 (54%) were more than 15 years of age. The median age was 20 years with a male: female ratio of 2.4:1. Ninety percent had skeletal EWS, 10% had extra skeletal EWS, and 37% patients were metastatic at presentation. Eighty-two received curative treatment with chemotherapy (vincristine, doxorubicin, cyclophosphamide, ifosfamide, etoposide (VAC/IE)) along with local treatment, radiotherapy (RT) in 61, surgery alone in seven, and RT plus surgery in 14. Two- and 5-year overall survival (OS) was 43.3% and 25.5%, respectively, for the entire series. The OS for the non-metastatic group was 63.2% at 2 years and 36.5% at 5 years, and the progression free survival was 53.7% at 2 years and 37.8% at 5 years. High lactate dehydrogenase was found to be a significant poor prognostic factor (P = 0.001). Median OS for localized central EWS was 49.2 months and that for peripheral EWS was 24 months. Patients more than 20 years of age with non-metastatic disease had better OS compared to those with 15-20 years of age. CONCLUSION: Treatment of EWS requires a multidisciplinary approach with radical surgery and/or radiation to control local disease and multiagent chemotherapy to control systemic disease. Long-term follow-up is essential because of disease relapse and treatment-related complications.


Assuntos
Neoplasias Ósseas , Sarcoma de Ewing , Adulto , Humanos , Masculino , Adolescente , Feminino , Adulto Jovem , Sarcoma de Ewing/epidemiologia , Sarcoma de Ewing/terapia , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/terapia , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ósseas/terapia , Neoplasias Ósseas/tratamento farmacológico , Ciclofosfamida , Ifosfamida , Doxorrubicina/uso terapêutico , Vincristina
3.
Med Int (Lond) ; 3(6): 56, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37927353

RESUMO

Castleman disease (CD) describes a group of rare heterogeneous lymphoproliferative disorders characterized by enlarged hyperplastic lymph nodes. It is classified into unicentric CD (UCD) and multicentric CD (MCD). The present retrospective study examined the data of 11 patients with CD diagnosed and treated at a tertiary cancer center from 2017 to 2022. The median age of the study group was 41 years (range, 24 to 68 years). There were 8 males and 3 females. In total, 7 patients were diagnosed with UCD and 4 patients with MCD. The hyaline-vascular variant was the most common histology in both UCD and MCD. Among the 7 patients with UCD, 5 patients underwent excision, 1 patient underwent debulking followed by radiotherapy and 1 patient received single agent rituximab. Of the patients with UCD, 6 had a complete response (CR) and 1 patient had a partial response (PR). All 4 patients with MCD received systemic treatment, which included single agent rituximab (2 patients), rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone (RCHOP) (1 patient) and CHOP (1 patient). Among the patients with MCD, 1 patient attained a CR, 2 patients had a PR and 1 patient succumbed. The 3-year survival rate for the study population was 91%. In summary, CD is a rare disease occurring in immunodeficient patients. UCD is more common and is associated with better outcomes. Surgery is the mainstay of management in UCD whereas MCD requires combination chemotherapy.

4.
ACS Nano ; 17(21): 20999-21005, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37708240

RESUMO

Controlling defect densities in SrRuO3 films is the cornerstone for probing the intricate relationship among its structural, electrical, and magnetic properties. We combine film growth, electrical transport, and magnetometry to demonstrate the adsorption-controlled growth of phase-pure, epitaxial, and stoichiometric SrRuO3 films on SrTiO3 (001) substrates using solid source metal-organic molecular beam epitaxy. Across the growth window, we show that the anomalous Hall curves arise from two distinct magnetic domains. Domains with similar anomalous Hall polarities generate the stepped feature observed within the growth window, and those with opposite polarities produce the hump-like feature present exclusively in the highly Ru-poor film. We achieve a residual resistivity ratio (RRR = ρ300K/ρ2K) of 87 in a 50 nm-thick, coherently strained, and stoichiometric SrRuO3 film, the highest reported value to date on SrTiO3 (001) substrates. We hypothesize further improvements in the RRR through strain engineering to control the tetragonal-to-orthorhombic phase transformation and the domain structure of SrRuO3 films.

5.
Nat Commun ; 14(1): 6005, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752136

RESUMO

Rich electron-matter interactions fundamentally enable electron probe studies of materials such as scanning transmission electron microscopy (STEM). Inelastic interactions often result in structural modifications of the material, ultimately limiting the quality of electron probe measurements. However, atomistic mechanisms of inelastic-scattering-driven transformations are difficult to characterize. Here, we report direct visualization of radiolysis-driven restructuring of rutile TiO2 under electron beam irradiation. Using annular dark field imaging and electron energy-loss spectroscopy signals, STEM probes revealed the progressive filling of atomically sharp nanometer-wide cracks with striking atomic resolution detail. STEM probes of varying beam energy and precisely controlled electron dose were found to constructively restructure rutile TiO2 according to a quantified radiolytic mechanism. Based on direct experimental observation, a "two-step rolling" model of mobile octahedral building blocks enabling radiolysis-driven atomic migration is introduced. Such controlled electron beam-induced radiolytic restructuring can be used to engineer novel nanostructures atom-by-atom.

7.
Nat Nanotechnol ; 18(9): 1005-1011, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37217765

RESUMO

The oxides of platinum group metals are promising for future electronics and spintronics due to the delicate interplay of spin-orbit coupling and electron correlation energies. However, their synthesis as thin films remains challenging due to their low vapour pressures and low oxidation potentials. Here we show how epitaxial strain can be used as a control knob to enhance metal oxidation. Using Ir as an example, we demonstrate the use of epitaxial strain in engineering its oxidation chemistry, enabling phase-pure Ir or IrO2 films despite using identical growth conditions. The observations are explained using a density-functional-theory-based modified formation enthalpy framework, which highlights the important role of metal-substrate epitaxial strain in governing the oxide formation enthalpy. We also validate the generality of this principle by demonstrating epitaxial strain effect on Ru oxidation. The IrO2 films studied in our work further revealed quantum oscillations, attesting to the excellent film quality. The epitaxial strain approach we present could enable growth of oxide films of hard-to-oxidize elements using strain engineering.

8.
Nat Struct Mol Biol ; 30(2): 148-158, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36747093

RESUMO

Enhancer activation serves as the main mechanism regulating signal-dependent transcriptional programs, ensuring cellular plasticity, yet central questions persist regarding their mechanism of activation. Here, by successfully mapping topoisomerase I-DNA covalent complexes genome-wide, we find that most, if not all, acutely activated enhancers, including those induced by 17ß-estradiol, dihydrotestosterone, tumor necrosis factor alpha and neuronal depolarization, are hotspots for topoisomerase I-DNA covalent complexes, functioning as epigenomic signatures read by the classic DNA damage sensor protein, Ku70. Ku70 in turn nucleates a heterochromatin protein 1 gamma (HP1γ)-mediator subunit Med26 complex to facilitate acute, but not chronic, transcriptional activation programs. Together, our data uncover a broad, unappreciated transcriptional code, required for most, if not all, acute signal-dependent enhancer activation events in both mitotic and postmitotic cells.


Assuntos
DNA Topoisomerases Tipo I , Elementos Facilitadores Genéticos , DNA , DNA Topoisomerases Tipo I/metabolismo , Fatores de Transcrição/metabolismo , Ativação Transcricional , Autoantígeno Ku/metabolismo
9.
Plant Methods ; 18(1): 110, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071455

RESUMO

Soybeans play a key role in global food security. U.S. soybean yields, which comprise [Formula: see text] of the total soybeans planted in the world, continue to experience unprecedented grain loss due to the soybean cyst nematode (SCN) plant pathogen. SCN remains one of the primary disruptive pests despite the existence of advanced management techniques such as crop rotation and SCN-resistant varieties. SCN detection is a key step in managing this disease; however, early detection is challenging because soybeans do not show any above ground symptoms unless they  are significantly damaged. Direct soil sampling remains the most common method for SCN detection, however, this method has several problems. For example, the threshold damage methods-adopted by most of the laboratories to make recommendations-is not reliable as it does not consider soil pH, N, P, and K values and relies solely on the egg count instead of assessment of the root infection. To overcome the challenges of manual soil sampling methods, deep learning and hyperspectral imaging are important current topics in precision agriculture for plant disease detection and have been proposed as cost-effective and efficient detection methods that can work at scale. We have reviewed more than 150 research papers focusing on soybean cyst nematodes with an emphasis on deep learning techniques for detection and management. First: we describe soybean vegetation and reproduction stages, SCN life cycles, and factors influencing this disease. Second: we highlight the impact of SCN on soybean yield loss and the challenges associated with its detection. Third: we describe direct sampling methods in which the soil samples are procured and analyzed to evaluate SCN egg counts. Fourth: we highlight the advantages and limitations of these direct methods, then review computer vision- and remote sensing-based detection methods: data collection using ground, aerial, and satellite approaches followed by a review of machine learning methods for image analysis-based soybean cyst nematode detection. We highlight the evaluation approaches and the advantages of overall detection workflow in high-performance and big data environments. Lastly, we discuss various management approaches, such as crop rotation, fertilization, SCN resistant varieties such as PI 88788, and SCN's increasing resistance to these strategies. We review machine learning approaches for soybean crop yield forecasting as well as the influence of pesticides, herbicides, and fertilizers on SCN infestation reduction. We provide recommendations for soybean research using deep learning and hyperspectral imaging to accommodate the lack of the ground truth data and training and testing methodologies, such as data augmentation and transfer learning, to achieve a high level of detection accuracy while keeping costs as low as possible.

10.
Proc Natl Acad Sci U S A ; 119(32): e2206216119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914133

RESUMO

The eukaryotic genome is partitioned into distinct topological domains separated by boundary elements. Emerging data support the concept that several well-established nuclear compartments are ribonucleoprotein condensates assembled through the physical process of phase separation. Here, based on our demonstration that chemical disruption of nuclear condensate assembly weakens the insulation properties of a specific subset (∼20%) of topologically associated domain (TAD) boundaries, we report that the disrupted boundaries are characterized by a high level of transcription and striking spatial clustering. These topological boundary regions tend to be spatially associated, even interchromosomally, segregate with nuclear speckles, and harbor a specific subset of "housekeeping" genes widely expressed in diverse cell types. These observations reveal a previously unappreciated mode of genome organization mediated by conserved boundary elements harboring highly and widely expressed transcription units and associated transcriptional condensates.


Assuntos
Compartimento Celular , Núcleo Celular , Eucariotos , Ribonucleoproteínas , Núcleo Celular/química , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cromossomos/genética , Eucariotos/citologia , Eucariotos/genética , Genes Essenciais , Genoma/genética , Salpicos Nucleares/genética , Ribonucleoproteínas/metabolismo , Transcrição Gênica
11.
Cureus ; 14(6): e25814, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35822135

RESUMO

Histiocytic sarcoma (HS) is an extremely rare histiocytic disorder of unknown etiology. It is not a true sarcoma and is named so, due to the pathological resemblance to mature histiocytes. The clinical presentation of HS is diverse and is related to the involved organs. Due to its aggressive nature, with poor prognosis and lack of a standard treatment regimen of choice, its diagnosis and management pose a challenge to the clinician. Limited literature is available on the management of this entity. Here, we report four patients with HS, diagnosed over 15 years in a tertiary cancer center, with varied clinical presentation, management, and outcomes. The first patient presented with a localized unresectable esophageal mass. He was treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) combination chemotherapy and attained complete remission. The second patient had a painless mass of the hand, treated with wide excision and adjuvant Radiotherapy. She is disease-free for the past 12 years. The third patient had presented with an anterior mediastinal mass. He had progressive disease on chemotherapy. The fourth patient had multifocal disease with generalized lymphadenopathy. She was treated with CHOP chemotherapy and is now disease-free at 13 months. To summarize, the patients with the localized resectable disease did well, with surgical excision and adjuvant radiotherapy, while patients with the multifocal disease did well on CHOP chemotherapy. The take-home message from this case series is - CHOP off whenever you can and if not give CHOP to chop off the disease.

12.
Trends Genet ; 38(10): 1019-1047, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35811173

RESUMO

Gene regulation by transcriptional enhancers is the dominant mechanism driving cell type- and signal-specific transcriptional diversity in metazoans. However, over four decades since the original discovery, how enhancers operate in the nuclear space remains largely enigmatic. Recent multidisciplinary efforts combining real-time imaging, genome sequencing, and biophysical strategies provide insightful but conflicting models of enhancer-mediated gene control. Here, we review the discovery and progress in enhancer biology, emphasizing the recent findings that acutely activated enhancers assemble regulatory machinery as mesoscale architectural structures with distinct physical properties. These findings help formulate novel models that explain several mysterious features of the assembly of transcriptional enhancers and the mechanisms of spatial control of gene expression.


Assuntos
DNA Viral , Elementos Facilitadores Genéticos , Sequência de Bases , Núcleo Celular/genética , Regulação da Expressão Gênica/genética
13.
J Cancer Res Ther ; 18(3): 697-703, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35900542

RESUMO

Background: t(8;21)(q22;q22) is the most frequent recurrent translocation in acute myeloid leukemia (AML) resulting in an in-frame fusion of RUNX1/RUNX1T1 that regulates various genes involved in the signaling pathways. This leukemogenic alteration is usually associated with a favorable clinical outcome. Variants of t(8;21) can be formed involving a third or fourth chromosome in ~3-4% of t(8;21)-AML. Due to the rarity of variant t(8;21), its clinicopathological features and prognostic significance are still unclear. Here we present three AML cases with cryptic rearrangements of chromosomes 8 and 21 without standard RUNX1/RUNX1T1. Materials and Methods: Conventional karyotyping and fluorescence in situ hybridization and/or spectral karyotyping of the pretreatment bone marrow aspirate of de novo AML patients were performed to delineate chromosomal abnormalities. Results: We identified three cases with novel variants of t(8;21); der(13)t(8;21;13), isodicentric derivative 8 with chromosome 21[,+idicder(8)(q11.1)t(8;21)(q22;q11.1)] and der(21)t(8;12;21)(q22;q?;q22). Conclusion: AML with t(8;21)(q22;q22);RUNX1-RUNX1T1 forms a distinct WHO subcategory and hence the identification of variants or unusual translocations associated with t(8;21) deserves more attention. Contribution to the variant/ unusual t(8;21) database will further refine the risk stratification and may help to significantly advance the current treatment regimen.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core , Leucemia Mieloide Aguda , Cromossomos , Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Translocação Genética
14.
JBJS Case Connect ; 12(1)2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35171851

RESUMO

CASE: Multifocal synchronous primary skeletal chondrosarcomas of an extremity are rarely reported. In this study, we report 2 such cases. The first case is a 32-year-old woman who presented with extensive right femoral and tibial diaphysis lesions. The second case is a 36-year-old woman with lesions in the left proximal humerus, the coracoid process of scapula and sternum. Both patients underwent limb salvage surgery and were disease-free at the 38- and 20-month follow-up. CONCLUSION: Athough rare, the possibility of multifocal chondrosarcoma should be kept in mind during the workup of a patient with chondrosarcoma.


Assuntos
Neoplasias Ósseas , Condrossarcoma , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Condrossarcoma/diagnóstico por imagem , Condrossarcoma/patologia , Condrossarcoma/cirurgia , Feminino , Humanos , Úmero/diagnóstico por imagem , Úmero/patologia , Úmero/cirurgia , Escápula/cirurgia , Ombro/patologia
15.
South Asian J Cancer ; 11(3): 256-259, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36588611

RESUMO

T.M. AnoopBackground The role of serum free light chain (FLC) as a prognostic biomarker in lymphoproliferative diseases is being increasingly studied. In this study we present the 5-year survival outcome for patients with aggressive B-cell non-Hodgkin's lymphoma (NHL) and their relation to FLC and other known prognostic markers. Materials and Methods This is a prospective study conducted in patients diagnosed with aggressive B-cell NHL. Serum FLC level and ratio were estimated prior to initiation of treatment. Results A total of 100 patients were included in the study from December 2013 to December 2015 with a median age of 53 years. Thirty-eight patients (38%) had elevated FLC level of which 26% were polyclonal and 12% were monoclonal elevations. Abnormal FLC ratio was noted in 12% patients. Median follow-up duration of the study was 75 months. Five-year relapse-free survival (RFS) for the study population was 54.4%. Five-year RFS was 64.1% for early stage and 48.2% for advanced stage diseases ( p = 0.05). The RFS was significantly better in age less than 60 years (59.5% vs 43.8%, p < 0.001). Five-year overall survival (OS) was 61.3%. OS was significantly better in younger patients (73.6% vs 33.4%, p < 0.001), with International Prognosis Index score of 0 to 2 (87.4% vs 26.7%, p < 0.001). Patients with elevated FLC had inferior RFS (50% vs 71.4%, p = 0.04). Abnormal FLC ratio also strongly corresponded to inferior RFS (54.5% vs 66.2%, p = 0.001). OS was also significantly inferior in patients with abnormal FLC ratio (72.6% vs 63.6%, p = 0.001). Conclusion In patients with newly diagnosed aggressive B-cell NHL, elevated FLC levels and abnormal FLC ratio were significantly associated with inferior survival.

16.
Int J Biol Macromol ; 182: 1769-1784, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34051259

RESUMO

This work attempts to resolve one of the key issues related to the design and development of sustained-release spherule of aspirin for oral formulations, tailored to treat COVID-19. For that, in the Design of Experiments (DOE) an arbitrary interface, "coating efficiency" (CE) is introduced and scaled the cumulative percentage coating (CPC) to get predictable control over drug release (DR). Subsequently, the granules containing ASP are converted to spherules and then to Ethyl cellulose (EC) Coated spherules (CS) by a novel bed coating during the rolling (BCDR) process. Among spherules, one with 0.35 mm than 0.71 mm shows required properties. The CS has a low 1200 angle by Optical Microscopy (OM), smooth surface without cracks by scanning electron microscopy (SEM), and better flow properties (Angle of repose 29.69 ± 0.780, Carr's index 6.73 ± 2.24%, Hausner's Ratio 1.07 ± 0.03) than granules and spherules. Once certain structure-dependent control over release is attained (EC coated spherules shows 10% reduction in burst release (BR) than uncoated spherules showing a release of 80-91%) the predictability is achieved and Design of space (DOS) by DOE (CE-70.14%and CPC-200% and DR-61.54%) is established. The results of DOE to experimentally validated results were within 20% deviation. The aspirin is changing its crystal structure by powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC) from Form-I to Form-II showing polymorphism inside the drug reservoir with respect to the process. This CE and CPC approach in DOE can be used for delivery system design of other labile drugs similar to aspirin in emergency situations.


Assuntos
Aspirina , Tratamento Farmacológico da COVID-19 , Celulose/análogos & derivados , SARS-CoV-2 , Aspirina/química , Aspirina/farmacocinética , Celulose/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Composição de Medicamentos , Liberação Controlada de Fármacos , Humanos
17.
Nature ; 595(7869): 735-740, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34040254

RESUMO

The functional engagement between an enhancer and its target promoter ensures precise gene transcription1. Understanding the basis of promoter choice by enhancers has important implications for health and disease. Here we report that functional loss of a preferred promoter can release its partner enhancer to loop to and activate an alternative promoter (or alternative promoters) in the neighbourhood. We refer to this target-switching process as 'enhancer release and retargeting'. Genetic deletion, motif perturbation or mutation, and dCas9-mediated CTCF tethering reveal that promoter choice by an enhancer can be determined by the binding of CTCF at promoters, in a cohesin-dependent manner-consistent with a model of 'enhancer scanning' inside the contact domain. Promoter-associated CTCF shows a lower affinity than that at chromatin domain boundaries and often lacks a preferred motif orientation or a partnering CTCF at the cognate enhancer, suggesting properties distinct from boundary CTCF. Analyses of cancer mutations, data from the GTEx project and risk loci from genome-wide association studies, together with a focused CRISPR interference screen, reveal that enhancer release and retargeting represents an overlooked mechanism that underlies the activation of disease-susceptibility genes, as exemplified by a risk locus for Parkinson's disease (NUCKS1-RAB7L1) and three loci associated with cancer (CLPTM1L-TERT, ZCCHC7-PAX5 and PVT1-MYC).


Assuntos
Fator de Ligação a CCCTC/genética , Elementos Facilitadores Genéticos , Predisposição Genética para Doença , Regiões Promotoras Genéticas , Sistemas CRISPR-Cas , Proteínas de Ciclo Celular/genética , Células Cultivadas , Cromatina , Proteínas Cromossômicas não Histona/genética , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Células MCF-7 , Neoplasias/genética , Células-Tronco Neurais , Oncogenes , Doença de Parkinson/genética , Coesinas
18.
Toxins (Basel) ; 12(5)2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32408589

RESUMO

Medium cut-off membrane (MCO) dialysers have been shown to remove a range of middle molecules, which are associated with adverse outcomes in haemodialysis (HD) patients, more effectively than high-flux HD. Vancomycin is widely used in HD patients for treating a variety of infections. To avoid subtherapeutic trough concentrations, it is important to understand vancomycin clearance in patients undergoing HD with the MCO membrane. This open label single centre, cross-over clinical study compared the vancomycin pharmacokinetics in chronic HD patients using MCO membrane (Theranova) and high-flux membrane (Revaclear). Five patients established on chronic HD who were due to receive vancomycin were enrolled. The study used alternating Theranova and Revaclear dialysis membranes over six consecutive sessions. Vancomycin was administered over the last one to two hours of each HD session. The maintenance dose was adjusted based on pre-HD serum concentrations. Over the 210 study samples, vancomycin clearance was higher with MCO-HD compared to high-flux HD but not statistically significant. Median percentage of vancomycin removal at 120 min by MCO membrane was 39% (20.6-51.5%) compared with 34.1% (21.3-48.4%) with high-flux HD. MCO-HD removes a slightly higher percentage of vancomycin at 120 min into dialysis compared to high-flux membrane dialysis in HD patients with infections. Application of vancomycin during the last one to two hours of each dialysis is required to maintain therapeutic concentrations to minimise loss through the dialyser and maintain therapeutic levels.


Assuntos
Antibacterianos/farmacocinética , Membranas Artificiais , Diálise Renal/instrumentação , Insuficiência Renal Crônica/terapia , Vancomicina/farmacocinética , Idoso , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Estudos Cross-Over , Monitoramento de Medicamentos , Desenho de Equipamento , Feminino , Humanos , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Peso Molecular , Porosidade , Diálise Renal/efeitos adversos , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/diagnóstico , Vancomicina/administração & dosagem , Vancomicina/sangue
19.
Cell Rep ; 31(3): 107532, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32320655

RESUMO

Cisplatin is an antineoplastic drug administered at suboptimal and intermittent doses to avoid life-threatening effects. Although this regimen shortly improves symptoms in the short term, it also leads to more malignant disease in the long term. We describe a multilayered analysis ranging from chromatin to translation-integrating chromatin immunoprecipitation sequencing (ChIP-seq), global run-on sequencing (GRO-seq), RNA sequencing (RNA-seq), and ribosome profiling-to understand how cisplatin confers (pre)malignant features by using a well-established ovarian cancer model of cisplatin exposure. This approach allows us to segregate the human transcriptome into gene modules representing distinct regulatory principles and to characterize that the most cisplatin-disrupted modules are associated with underlying events of super-enhancer plasticity. These events arise when cancer cells initiate without ultimately ending the program of drug-stimulated death. Using a PageRank-based algorithm, we predict super-enhancer regulator ISL1 as a driver of this plasticity and validate this prediction by using CRISPR/dCas9-KRAB inhibition (CRISPRi) and CRISPR/dCas9-VP64 activation (CRISPRa) tools. Together, we propose that cisplatin reprograms cancer cells when inducing them to undergo near-to-death experiences.


Assuntos
Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Elementos Facilitadores Genéticos/genética , Neoplasias/genética , Transcrição Gênica/genética , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Humanos
20.
Int J Hematol Oncol Stem Cell Res ; 14(4): 226-231, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33603983

RESUMO

Background: The half-life of free light chain is short and can be used as an early marker for tumor response in patients with multiple myeloma [MM]. This prospective study is aimed at evaluating whether early light chain response can predict response to treatment in patients with MM. Materials and Methods: Thirty six patients with a diagnosis of MM and with an abnormal to normal light chain ratio of > 10 were included in this study. Results: The median age at presentation was 56 years. Fourteen patients had lambda light chain disease, whereas 22 patients had kappa light chain disease. Twenty-four patients [66.6%] had reduction of abnormal to normal light chain ratio to < 10 after 2 cycles, of whom 15 [62.5%] achieved a CR or VGPR after 6 cycles. Among 12 patients who did not have reduction of abnormal to normal light chain ratio to < 10, only 1 patient achieved CR while 11 patients [91.6%] achieved a PR or less[Fishers exact p=0.004]. Median follow-up was 13 months. Median progression-free survival for the entire cohort was 15 months. One-year Progression-Free Survival was 77% vs 57.1%, [p= 0.008], respectively for patients with early normalization and those who did not show early normalization. Conclusion: Early light chain response after 2 cycles of chemotherapy is a good predictor for treatment response in patients with MM treated with bortezomib based chemotherapy. Treatment intensification based on early light chain response merits further evaluation in a prospective trial.

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