Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 55
Filtrar
1.
J Biol Chem ; : 107460, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38876306

RESUMO

Obesity is a major risk factor for liver and cardiovascular diseases. However, obesity-driven mechanisms that contribute to the pathogenesis of multiple organ diseases are still obscure and treatment is inadequate. We hypothesized that increased glucose-6-phosphate dehydrogenase (G6PD), the key rate-limiting enzyme in the pentose shunt, is critical in evoking metabolic reprogramming in multiple organs and is a significant contributor to the pathogenesis of liver and cardiovascular diseases. G6PD is induced by carbohydrate-rich diet and insulin. Long-term (8 months) high-fat diet (HFD) feeding increased body weight and elicited metabolic reprogramming in visceral fat, liver, and aorta, of the wild-type rats. In addition, HFD increased inflammatory chemokines in visceral fat. Interestingly, CRISPR-edited loss-of-function Mediterranean G6PD variant (G6PDS188F) rats, which mimic human polymorphism, moderated HFD-induced weight gain and metabolic reprogramming in visceral fat, liver, and aorta. The G6PDS188F variant prevented HFD-induced CCL7 and adipocyte hypertrophy. Furthermore, the G6PDS188F variant increased Magel2 - a gene encoding circadian clock-related protein that suppresses obesity associated with Prader-Willi syndrome - and reduced HFD-induced non-alcoholic fatty liver. Additionally, the G6PDS188F variant reduced aging-induced aortic stiffening. Our findings suggest G6PD is a regulator of HFD-induced obesity, adipocyte hypertrophy, and fatty liver.

2.
PLoS Comput Biol ; 18(6): e1009657, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35666771

RESUMO

Model-checking is a methodology developed in computer science to automatically assess the dynamics of discrete systems, by checking if a system modelled as a state-transition graph satisfies a dynamical property written as a temporal logic formula. The dynamics of ecosystems have been drawn as state-transition graphs for more than a century, ranging from state-and-transition models to assembly graphs. Model-checking can provide insights into both empirical data and theoretical models, as long as they sum up into state-transition graphs. While model-checking proved to be a valuable tool in systems biology, it remains largely underused in ecology apart from precursory applications. This article proposes to address this situation, through an inventory of existing ecological STGs and an accessible presentation of the model-checking methodology. This overview is illustrated by the application of model-checking to assess the dynamics of a vegetation pathways model. We select management scenarios by model-checking Computation Tree Logic formulas representing management goals and built from a proposed catalogue of patterns. In discussion, we sketch bridges between existing studies in ecology and available model-checking frameworks. In addition to the automated analysis of ecological state-transition graphs, we believe that defining ecological concepts with temporal logics could help clarify and compare them.


Assuntos
Ecossistema , Biologia de Sistemas , Lógica , Modelos Teóricos , Resolução de Problemas
3.
Entropy (Basel) ; 25(11)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37998218

RESUMO

Ecosystem modeling is a complex and multidisciplinary modeling problem which emerged in the 1950s. It takes advantage of the computational turn in sciences to better understand anthropogenic impacts and improve ecosystem management. For that purpose, ecosystem simulation models based on difference or differential equations were built. These models were relevant for studying dynamical phenomena and still are. However, they face important limitations in data-poor situations. As a response, several formal and non-formal qualitative dynamical modeling approaches were independently developed to overcome some limitations of the existing methods. Qualitative approaches allow studying qualitative dynamics as relevant abstractions of those provided by quantitative models (e.g., response to press perturbations). Each modeling framework can be viewed as a different assemblage of properties (e.g., determinism, stochasticity or synchronous update of variable values) designed to satisfy some scientific objectives. Based on four stated objectives commonly found in complex environmental sciences ((1) grasping qualitative dynamics, (2) making as few assumptions as possible about parameter values, (3) being explanatory and (4) being predictive), our objectives were guided by the wish to model complex and multidisciplinary issues commonly found in ecosystem modeling. We then discussed the relevance of existing modeling approaches and proposed the ecological discrete-event networks (EDEN) modeling framework for this purpose. The EDEN models propose a qualitative, discrete-event, partially synchronous and possibilistic view of ecosystem dynamics. We discussed each of these properties through ecological examples and existing analysis techniques for such models and showed how relevant they are for environmental science studies.

4.
Mol Cell ; 53(5): 831-42, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24508391

RESUMO

Dynamically controlled posttranslational modifications of nucleosomal histones alter chromatin condensation to regulate transcriptional activation. We report that a nuclear tandem kinase, JIL-1, controls gene expression by activating poly(ADP-ribose) polymerase-1 (PARP-1). JIL-1 phosphorylates the C terminus of the H2Av histone variant, which stimulates PARP-1 enzymatic activity in the surrounding chromatin, leading to further modification of histones and chromatin loosening. The H2Av nucleosome has a higher surface representation of PARP-1 binding patch, consisting of H3 and H4 epitopes. Phosphorylation of H2Av by JIL-1 restructures this surface patch, leading to activation of PARP-1. Exposure of Val61 and Leu23 of the H4 histone is critical for PARP-1 binding on nucleosome and PARP-1 activation following H2Av phosphorylation. We propose that chromatin loosening and associated initiation of gene expression is activated by phosphorylation of H2Av in a nucleosome positioned in promoter regions of PARP-1-dependent genes.


Assuntos
Proteínas de Drosophila/química , Histonas/química , Nucleossomos/química , Poli Adenosina Difosfato Ribose/metabolismo , Poli(ADP-Ribose) Polimerases/química , Animais , Cromatina/química , DNA/química , Drosophila/genética , Proteínas de Drosophila/metabolismo , Epitopos/química , Imuno-Histoquímica , Nuclease do Micrococo/metabolismo , Modelos Moleculares , Conformação Molecular , Fases de Leitura Aberta , Fosforilação , Poli(ADP-Ribose) Polimerase-1 , Poli Adenosina Difosfato Ribose/genética , Regiões Promotoras Genéticas , Conformação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
5.
Proc Natl Acad Sci U S A ; 116(20): 9941-9946, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31028139

RESUMO

Poly(ADP-ribose) polymerase 1 (PARP-1) is a multidomain multifunctional nuclear enzyme involved in the regulation of the chromatin structure and transcription. PARP-1 consists of three functional domains: the N-terminal DNA-binding domain (DBD) containing three zinc fingers, the automodification domain (A), and the C-terminal domain, which includes the protein interacting WGR domain (W) and the catalytic (Cat) subdomain responsible for the poly(ADP ribosyl)ating reaction. The mechanisms coordinating the functions of these domains and determining the positioning of PARP-1 in chromatin remain unknown. Using multiple deletional isoforms of PARP-1, lacking one or another of its three domains, as well as consisting of only one of those domains, we demonstrate that different functions of PARP-1 are coordinated by interactions among these domains and their targets. Interaction between the DBD and damaged DNA leads to a short-term binding and activation of PARP-1. This "hit and run" activation of PARP-1 initiates the DNA repair pathway at a specific point. The long-term chromatin loosening required to sustain transcription takes place when the C-terminal domain of PARP-1 binds to chromatin by interacting with histone H4 in the nucleosome. This long-term activation of PARP-1 results in a continuous accumulation of pADPr, which maintains chromatin in the loosened state around a certain locus so that the transcription machinery has continuous access to DNA. Cooperation between the DBD and C-terminal domain occurs in response to heat shock (HS), allowing PARP-1 to scan chromatin for specific binding sites.


Assuntos
Poli(ADP-Ribose) Polimerase-1/metabolismo , Animais , Cromatina/metabolismo , Drosophila , Ativação Enzimática , Histonas/metabolismo , Domínios Proteicos , Ativação Transcricional
6.
Plant Dis ; 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35581909

RESUMO

First Report of Didymella rhei causing leaf spot on rhubarb in New York E. J. Indermaur1, C. T. C. Day1, and C. D. Smart1† 1School of Integrative Plant Science, Section of Plant Pathology and Plant-Microbe Biology, Cornell University, Geneva NY 14456 †Corresponding author: C. D. Smart; Email: cds14@cornell.edu Rhubarb (Rheum spp.) is a perennial grown across the northern United States for petiole production (Foust & Marshall 1991). In August 2021, leaf spots were observed on rhubarb growing in a two-acre field in Erie Co., NY (Fig. S1). Approximately 30% of the plants in the field had leaf spot with disease severity of 5%. Initial symptoms on leaves were light brown, circular lesions with red margins that later coalesced into irregular spots. Lesion centers were dry with concentric rings, often perforating as they enlarged. Lesions on petioles were light brown, fusiform, and sunken with red margins. To identify the causal agent(s), symptomatic leaves and petioles from 50 plants (cultivar unknown) were collected with a W-shape sampling scheme. Lesion margins were surface sterilized with 70% ethanol for 60 s, 10% bleach for 60 s, rinsed in sterile water, plated on acidified potato dextrose agar (PDA), and incubated for two to four days at 20˚C. Hyphal tips from colony edges were transferred to new PDA plates. After 20 days, colonies (n=53) were olivaceous buff to grey olivaceous, producing white to grey, sparse aerial mycelium. Brown to black pycnidia were produced within five days in concentric rings around plate centers. Pycnidia were globose to subglobose, with one to two non-papillate or slightly papillate ostioles, and with mean diameter 75.8 (30.8 to 113.5) µm (n=20). Conidia were hyaline, ellipsoid or allantoid, and aseptate with mean ± SD dimensions of 6.2 ± 0.4 (4.9 to 8.1) x 2.2 ± 0.4 (1.3 to 3.3) µm (n=30) (Fig. S2). Based on these morphological characteristics, the isolates were initially identified as Didymella rhei [Ellis & Everh] (Qian Chen & L. Cai) (Boerema 2004). To confirm the identity, mycelia were scraped from PDA plates and homogenized using a TissueLyser II (Qiagen Inc.). Genomic DNA was extracted with a DNeasy Plant Mini Kit following manufacturer's instructions (Qiagen Inc.). PCR assays with primers ITS 4 and ITS 5 and fRPB2-7cR and RPB2-5F2 (Liu et al. 1999; Sung et al. 2007) were used to amplify the internal transcribed spacer (ITS) and the rpb2 gene regions of one representative isolate (strain RHU21204). Products were sequenced using Sanger chemistry. The sequences were deposited in GenBank with accession numbers OM903952 (ITS) and OM925897 (rpb2). The ITS and rpb2 sequences exhibited 99% (492/494 bp) and 100% (846/846 bp) identity with D. rhei accessions KF531831.1 and KP330428.1, respectively. Based on morphological and molecular characteristics, the pathogen was identified as D. rhei. To fulfill Koch's postulates, healthy leaves and petioles of four rhubarb seedlings (cultivars unknown) were spray-inoculated with a conidial suspension (1 × 107 conidia/ml) containing 0.2% Tween-20 from strain RHU21204. A tween suspension with no conidia was used as a control. Each treatment had three replicates. After inoculation, plants were placed in a 19˚C growth chamber with a 12-h photoperiod and misted for 30 min twice daily to maintain humidity above 80%. Initial symptoms were observed five days post inoculation (dpi), while control plants were asymptomatic. The pathogen was isolated 21 dpi from inoculated leaves and petioles with symptoms as described above (Fig. S1) and identified morphologically and molecularly as D. rhei. A representative isolate was deposited in the Cornell Plant Pathology Herbarium as CUP-070923. To our knowledge, this is the first report of D. rhei causing rhubarb leaf spot in New York and reducing the health and marketability of its host. Funding Source This project was funded by the College of Agriculture and Life Sciences, Cornell University. Literature Cited Boerema, G. H. et al. 2004. CABI Publishing. 288. Foust, C. M. and Marshall, D. E. 1991. HortScience 26:1360. DOI: 10.21273/HORTSCI.26.11.1360 Liu, Y. J. et al. 1999. Mol. Biol. Evol. 16:1799. Sung, G. H. et al. 2007. Mol. Phylogenet. Evol. 44:1204. DOI: 10.1016/j.ympev.2007.03.011.

7.
J Assist Reprod Genet ; 36(4): 655-660, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30834464

RESUMO

PURPOSE: To study the relationship between liquid nitrogen loss and temperature in cryostorage dewars and develop an early-warning alarm for impending tank failure. METHODS: Cryostorage dewars were placed on custom-engineered scales, and weight and temperature data were continuously monitored in the setting of slow, medium, and fast rate-loss of LN2 to simulate three scenarios of tank failure. RESULTS: LN2 Tank weights and temperatures were continuously monitored and recorded, with a calculated alarm trigger set at 10% weight loss and temperature of - 185 °C. With an intact tank, a 10% loss in LN2 occurred in 4.2-4.9 days. Warming to - 185 °C occurred in 37.8-43.7 days, over 30 days after the weight-based alarm was triggered. Full evaporation of LN2 required ~ 36.8 days. For the medium rate-loss simulation, a 10% loss in LN2 occurred in 0.8 h. Warming to - 185 °C occurred in 3.7-4.8 h, approximately 3 h after the weight-based alarm was triggered. For the fast rate-loss simulation, a 10% weight loss occurred within 15 s, and tanks were depleted in under 3 min. Tank temperatures began to rise immediately and at a relatively constant rate of 43.9 °C/h and 51.6 °C/h. Temperature alarms would have sounded within 0.37 and 0.06 h after the breech. CONCLUSIONS: This study demonstrates that a weight-based alarm system can detect tank failures prior to a temperature-based system. Weight-based monitoring could serve as a redundant safety mechanism for added protection of cryopreserved reproductive tissues.


Assuntos
Criopreservação/métodos , Nitrogênio/fisiologia , Preservação do Sêmen/métodos , Feminino , Humanos , Nitrogênio/química , Motilidade dos Espermatozoides/fisiologia
8.
J Immunol ; 197(6): 2382-9, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27527593

RESUMO

Regulation of NF-κB nuclear translocation and stability is central to mounting an effective innate immune response. In this article, we describe a novel molecular mechanism controlling NF-κB-dependent innate immune response. We show that a previously unknown protein, termed as Charon, functions as a regulator of antibacterial and antifungal immune defense in Drosophila Charon is an ankyrin repeat-containing protein that mediates poly(ADP-ribose) polymerase-1 (PARP-1)-dependent transcriptional responses downstream of the innate immune pathway. Our results demonstrate that Charon interacts with the NF-κB ortholog Relish inside perinuclear particles and delivers active Relish to PARP-1-bearing promoters, thus triggering NF-κB/PARP-1-dependent transcription of antimicrobial peptides. Ablating the expression of Charon prevents Relish from targeting promoters of antimicrobial genes and effectively suppresses the innate immune transcriptional response. Taken together, these results implicate Charon as an essential mediator of PARP-1-dependent transcription in the innate immune pathway. Thus, to our knowledge, our results are the first to describe the molecular mechanism regulating translocation of the NF-κB subunit from cytoplasm to chromatin.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica , NF-kappa B/metabolismo , Poli(ADP-Ribose) Polimerase-1/imunologia , Animais , Proteínas de Transporte/genética , Proteínas de Ligação a DNA/genética , Drosophila , Proteínas de Drosophila/genética , Proteínas de Drosophila/imunologia , Imunidade Inata , NF-kappa B/imunologia , Regiões Promotoras Genéticas , Fatores de Transcrição/imunologia , Fatores de Transcrição/metabolismo , Ativação Transcricional
9.
Crit Rev Food Sci Nutr ; 56(7): 1222-30, 2016 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-25674836

RESUMO

Bruising and other mechanical damage to fruit caused by external forces during and postharvesting is manifested at the macroscale but is ultimately the result of failure of cells at the microscale. However, fruits have internal structures and cells from different tissue types react differently to application of an external force. Not much is known about the effects of such forces on single cells within tissues and one reason for this is the lack of multiscale models linking macro- (organ or whole fruit), meso- (tissue), and micro- (cell) mechanics. This review concerns tomato fruits specifically as this is an important crop and is an excellent exemplar of past and proposed research in this field. The first consideration is the multiscale anatomy of tomato fruits that provides the basis for mechanical modeling. The literature on experimental methods for studying multiscale mechanics of fruit is then reviewed, as are recent results from using those methods. Finally, future research directions are discussed, in particular the combination of work over all scales. It is clear that a bottom-up approach incorporating single-cell mechanics in finite element models of whole fruit assumed to have internal structures is a promising way forward for tomato fruits but further method developments may be needed for these and other fruits and vegetables, in particular recovery of representative single cells from tissues for mechanical characterization.


Assuntos
Frutas , Solanum lycopersicum , Fenômenos Biomecânicos , Conservação de Alimentos , Qualidade dos Alimentos , Frutas/citologia , Modelos Biológicos
10.
Biotechnol Bioeng ; 111(1): 196-201, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23860965

RESUMO

Transgenic tobacco roots offer a potential alternative to leaves for monoclonal antibody (MAb) production. A possible method for extraction of MAbs from roots is by homogenization, breaking the roots into fragments to release the antibody. This process was assessed by shearing 10 mm root sections ("roots") in a 24 mL ultra-scale down shearing device, including an impeller with serrated blade edges, intended to mimic the action of a large-scale homogenizer. Size distributions of the remaining intact roots and root fragments were obtained as a function of shearing time. The data suggest that about 36% of the roots could not be broken under the prevailing conditions and, beyond these unbreakable roots, the fragmentation was approximately first order with respect to intact root number. It was postulated that root breakage in such a high shearing device was due to root-impeller collisions and the particle size data suggest that roots colliding with the impeller were completely fragmented into debris particles of the order of 0.1 mm in length. IgG release normalized to release by grinding appeared to lag behind the number of roots that had fragmented, suggesting that a process of leakage followed fragmentation in the ultra-scale down shearing device.


Assuntos
Anticorpos Monoclonais/metabolismo , Biotecnologia/instrumentação , Imunoglobulina G/metabolismo , Nicotiana/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas/metabolismo , Anticorpos Monoclonais/análise , Biotecnologia/métodos , Imunoglobulina G/análise
11.
Cancers (Basel) ; 16(10)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38792015

RESUMO

Mantle cell lymphoma (MCL) is a rare, heterogeneous B-cell non-Hodgkin's lymphoma. The standard front-line treatment utilizes chemotherapy, often followed by consolidation with an autologous hematopoietic cell transplant; however, in most patients, the lymphoma will recur and require subsequent treatments. Additionally, mantle cell lymphoma primarily affects older patients and is frequently chemotherapy-resistant, which has further fostered the necessity for new, chemotherapy-free treatment options. In the past decade, targeted therapies in mantle cell lymphoma have been practice-changing as the treatment paradigm shifts further away from relying primarily on cytotoxic agents. Here, we will review the pathophysiology of mantle cell lymphoma and discuss the emergence of targeted, chemotherapy-free treatments aimed at disrupting the abnormal biology driving its lymphomagenesis. Treatments targeting the constitutive activation of NF-kB, Bruton's Tyrosine Kinase signaling, and anti-apoptosis will be the primary focus as we discuss their clinical data and toxicities. Our review will also focus primarily on the emergence and use of targeted therapies in the relapsed/refractory setting but will also discuss the emergence of their use in front-line therapy and in combination with other agents.

12.
Eur Biophys J ; 42(8): 613-20, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23653094

RESUMO

The elastic modulus of the Baker's yeast (Saccharomyces cerevisiae) cell wall reported in studies using atomic force microscopy (AFM) is two orders of magnitude lower than that obtained using whole cell compression by micromanipulation. Using finite element modelling, it is shown that Hertz-Sneddon analysis cannot be applied to AFM indentation data for single layer core-shell structures. In addition, the Reissner solution for shallow homogeneous spheres is not appropriate for thick walls such as those of yeast cells. In order to explain yeast compression measurements at different length scales, a double layer wall model is presented considering a soft external layer composed of mannoproteins, and a stiff inner layer of ß-glucan fibres and chitin. Under this model, previous AFM studies using sharp indenters provide reasonable estimates of the external layer elastic modulus, while micromanipulation provides the total stiffness of the cell wall. Data from both measurements are combined to estimate the mechanical properties of the inner stiff layer.


Assuntos
Parede Celular , Fenômenos Mecânicos , Modelos Biológicos , Saccharomyces cerevisiae/citologia , Fenômenos Biomecânicos , Elasticidade , Análise de Elementos Finitos , Microscopia de Força Atômica
13.
Front Oncol ; 13: 1275800, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37927464

RESUMO

Nearly a billion people worldwide are infected with the hepatitis B Virus (HBV) and about a third of them have chronic infection. HBV is an important cause of morbidity and mortality, including acute and chronic hepatitis and hepatocellular carcinoma (HCC). Screening and control of primary HBV infection through vaccination represent a major advance in global public health, but large sections of the world population, in both developed and underdeveloped countries, remain unscreened and unvaccinated. In addition to being a global cause of liver disease, an important role of HBV in lymphoma has also emerged. First, the high risk of HBV reactivation in previously infected patients receiving chemo-immunotherapy necessitates the systematic evaluation of HBV serological status in all non-Hodgkin's lymphoma (NHL) cases and preemptive antiviral therapy for those who may have chronic or occult HBV infection. Second, HBV has been shown to infect lymphocytes, namely B-cells, and has been associated with a higher risk of developing B-cell lymphoma, most clearly in countries where HBV is endemic. While the risk of HBV reactivation with chemoimmunotherapy in NHL is well known, the role and the impact of HBV as a global lymphoma risk factor and potential oncogenic driver in B-cells are very poorly understood. Here, we review the clinical and scientific evidence supporting an association between HBV and B-cell lymphoma, with a particular focus on diffuse large B-cell lymphoma (DLBCL) and provide an overview of the estimated impact of HBV infection on the biology and clinical course of DLBCL. We also discuss ways to gain a better insight into the unmet need posed by HBV in lymphoma and whether assessing immune responses to HBV, measuring viral loads, and detecting the presence of HBV-encoded proteins in tumor tissue could be integrated into the molecular and clinical risk stratification of patients with DLBCL.

14.
Blood Adv ; 7(17): 5038-5046, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37315169

RESUMO

Given the paucity of data surrounding the prognostic relevance of monoclonal paraprotein (M-protein) in marginal zone lymphoma (MZL), we sought to evaluate the impact of detecting M-protein at diagnosis on outcomes in patients with MZL in a large retrospective cohort. The study included 547 patients receiving first-line therapy for MZL. M-protein was detectable at diagnosis in 173 (32%) patients. There was no significant difference in the time from diagnosis to initiation of any therapy (systemic and local) between the M-protein and no M-protein groups. Patients with M-protein at diagnosis had significantly inferior progression-free survival (PFS) compared with those without M-protein at diagnosis. After adjusting for factors associated with inferior PFS in univariate models, presence of M-protein remained significantly associated with inferior PFS (hazard ratio, 1.74; 95% confidence interval, 1.20-2.54; P = .004). We observed no significant difference in the PFS based on the type or quantity of M-protein at diagnosis. There were differential outcomes in PFS based on the first-line therapy in patients with M-protein at diagnosis, in that, those receiving immunochemotherapy had better outcomes compared with those receiving rituximab monotherapy. The cumulative incidence of relapse in stage 1 disease among the recipients of local therapy was higher in the presence of M-protein; however, this did not reach statistical significance. We found that M-protein at diagnosis was associated with a higher risk of histologic transformation. Because the PFS difference related to presence of M-protein was not observed in patients receiving bendamustine and rituximab, immunochemotherapy may be a preferred approach over rituximab monotherapy in this group and needs to be explored further.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma , Humanos , Rituximab/uso terapêutico , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Linfoma/tratamento farmacológico
15.
J Hematol Oncol ; 16(1): 49, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37158890

RESUMO

Progression of disease within 24 months (POD24) from diagnosis in marginal zone lymphoma (MZL) was shown to portend poor outcomes in prior studies. However, many patients with MZL do not require immediate therapy, and the time from diagnosis-to-treatment interval can be highly variable with no universal criteria to initiate systemic therapy. Hence, we sought to evaluate the prognostic relevance of early relapse or progression within 24 months from systemic therapy initiation in a large US cohort. The primary objective was to evaluate the overall survival (OS) in the two groups. The secondary objective included the evaluation of factors predictive of POD24 and the assessment of cumulative incidence of histologic transformation (HT) in POD24 versus non-POD24 groups. The study included 524 patients with 143 (27%) in POD24 and 381 (73%) in non-POD24 groups. Patients with POD24 had inferior OS compared to those without POD24, regardless of the type of systemic therapy received (rituximab monotherapy or immunochemotherapy) at diagnosis. After adjusting for factors associated with inferior OS in the univariate Cox model, POD24 remained associated with significantly inferior OS (HR = 2.50, 95% CI = 1.53-4.09, p = 0.0003) in multivariable analysis. The presence of monoclonal protein at diagnosis and those who received first-line rituximab monotherapy had higher odds of POD24 on logistic regression analysis. Patients with POD24 had a significantly higher risk for HT compared to those without POD24. POD24 in MZL might be associated with adverse biology and could be used as an additional information point in clinical trials and investigated as a marker for worse prognosis.


Assuntos
Imunoterapia , Linfoma , Humanos , Rituximab/uso terapêutico , Anticorpos Monoclonais , Recidiva
16.
J Hematol Oncol ; 15(1): 96, 2022 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842643

RESUMO

Ibrutinib is effective in the treatment of relapsed/refractory (R/R) marginal zone lymphoma (MZL) with an overall response rate (ORR) of 48%. However, factors associated with response (or lack thereof) to ibrutinib in R/R MZL in clinical practice are largely unknown. To answer this question, we performed a multicenter (25 US centers) cohort study and divided the study population into three groups: "ibrutinib responders"-patients who achieved complete or partial response (CR/PR) to ibrutinib; "stable disease (SD)"; and "primary progressors (PP)"-patients with progression of disease as their best response to ibrutinib. One hundred and nineteen patients met the eligibility criteria with 58%/17% ORR/CR, 29% with SD, and 13% with PP. The median PFS and OS were 29 and 71.4 months, respectively, with no difference in PFS or OS based on the ibrutinib line of therapy or type of therapy before ibrutinib. Patients with complex cytogenetics had an inferior PFS (HR = 3.08, 95% CI 1.23-7.67, p = 0.02), while those with both complex cytogenetics (HR = 3.00, 95% CI 1.03-8.68, p = 0.04) and PP (HR = 13.94, 95% CI 5.17-37.62, p < 0.001) had inferior OS. Only primary refractory disease to first-line therapy predicted a higher probability of PP to ibrutinib (RR = 3.77, 95% CI 1.15-12.33, p = 0.03). In this largest study to date evaluating outcomes of R/R MZL treated with ibrutinib, we show that patients with primary refractory disease and those with PP on ibrutinib are very high-risk subsets and need to be prioritized for experimental therapies.


Assuntos
Linfoma de Zona Marginal Tipo Células B , Adenina/análogos & derivados , Estudos de Coortes , Humanos , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Linfoma de Zona Marginal Tipo Células B/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Piperidinas , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Resultado do Tratamento
17.
Appl Opt ; 50(28): 5408-21, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22016207

RESUMO

The achievement of new satellite or airborne remote sensing instruments enables the more precise study of cities with metric spatial resolutions. For studies such as the radiative characterization of urban features, knowledge of the atmosphere and particularly of aerosols is required to perform first an atmospheric compensation of the remote sensing images. However, to our knowledge, no efficient aerosol characterization technique adapted both to urban areas and to very high spatial resolution images has yet been developed. The goal of this paper is so to present a new code to characterize aerosol optical properties, OSIS, adapted to urban remote sensing images of metric spatial resolution acquired in the visible and near-IR spectral domains. First, a new aerosol characterization method based on the observation of shadow/sun transitions is presented, offering the advantage to avoid the assessment of target reflectances. Its principle and the modeling of the signal used to solve the retrieval equation are then detailed. Finally, a sensitivity study of OSIS from synthetic images simulated by the radiative transfer code AMARTIS v2 is also presented. This study has shown an intrinsic precision of this tool of Δτ(a)=0.1.τ(a) ± (0.02 + 0.4.τ(a)) for retrieval of aerosol optical thicknesses. This study shows that OSIS is a powerful tool for aerosol characterization that has a precision similar to satellite products for the aerosol optical thicknesses retrieval and that can be applied to every very high spatial resolution instrument, multispectral or hyperspectral, airborne or satellite.

18.
Biotechnol Lett ; 33(7): 1395-405, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21365289

RESUMO

Based on two staining protocols, DiOC(6)(3)/propidium iodide (PI) and RedoxSensor Green (an indicator of bacterial reductase activity)/PI, multi-parameter flow cytometry and cell sorting has identified at least four distinguishable physiological states during batch cultures of Bacillus cereus. Furthermore, dependent on the position in the growth curve, single cells gave rise to varying numbers of colonies when sorted individually onto nutrient agar plates. These growing colonies derived from a single cell had widely different lag phases, inferred from differences in colony size. This further highlights the complex population dynamics of bacterial monocultures and further demonstrates that individual bacterial cells in a culture respond in markedly dissimilar ways to the environment, resulting in a physiologically heterogenous and dynamic population.


Assuntos
Bacillus cereus/crescimento & desenvolvimento , Variação Genética , Bacillus cereus/classificação , Citometria de Fluxo , Corantes Fluorescentes/metabolismo , Coloração e Rotulagem/métodos
19.
Biotechnol Lett ; 33(11): 2325-35, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21769648

RESUMO

The effects on human mesenchymal stem cell growth of choosing either of two spinner flask impeller geometries, two microcarrier concentrations and two cell concentrations (seeding densities) were investigated. Cytodex 3 microcarriers were not damaged when held at the minimum speed, N(JS), for their suspension, using either impeller, nor was there any observable damage to the cells. The maximum cell density was achieved after 8-10 days of culture with up to a 20-fold expansion in terms of cells per microcarrier. An increase in microcarrier concentration or seeding density generally had a deleterious or neutral effect, as previously observed for human fibroblast cultures. The choice of impeller was significant, as was incorporation of a 1 day delay before agitation to allow initial attachment of cells. The best conditions for cell expansion on the microcarriers in the flasks were 3,000 microcarriers ml(-1) (ca. 1 g dry weight l(-1)), a seeding density of 5 cells per microcarrier with a 1 day delay before agitation began at N(JS) (30 rpm), using a horizontally suspended flea impeller with an added vertical paddle. These findings were interpreted using Kolmogorov's theory of isotropic turbulence.


Assuntos
Reatores Biológicos , Proliferação de Células , Dextranos , Células-Tronco Mesenquimais/fisiologia , Microesferas , Contagem de Células , Técnicas de Cultura de Células , Células Cultivadas , Meios de Cultura , Humanos
20.
Palliat Med Rep ; 2(1): 132-136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34223512

RESUMO

Background: Adequate end-of-life (EOL) care/breaking-bad-news (BBN) discussions with patients are becoming increasingly essential to adequate patient care. Purpose: Whether a half-day workshop would lead to improved confidence in EOL/BBN care discussions for internal medicine interns. Methods: Internal medicine interns (n = 43) were assigned to participate in a half-day workshop at Thomas Jefferson University Hospital. The workshop involved two standardized patient (SP) interactions involving delivering news of a terminal illness/initiating goals of care discussion with the intervention of SP feedback, a didactic and lecture on proper EOL/BBN discussion. Voluntary anonymous surveys before and after the workshop were utilized to assess impact. Results: A majority of interns felt more comfortable with leading EOL care/BBN discussions after the workshop and had a positive experience. Conclusions: A half-day curriculum is efficacious in educating EOL/BBN communication to internal medicine interns, but should be further assessed in a larger more standardized study involving an objective assessment.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA