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1.
Hematol Oncol ; 42(1): e3222, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37740931

RESUMO

Venetoclax, a potent BCL-2 inhibitor, is currently under development for treatment of t(11;14) Multiple myeloma (MM). The objective of this research was to investigate the exposure-response relationships of venetoclax for a phase 1/2 study evaluating venetoclax monotherapy or in combination with dexamethasone in relapsed or refractory MM. A total of 117 patients receiving venetoclax at 300, 600, 800, 900, or 1200 mg were included in the analysis. The impact of venetoclax exposures on efficacy (objective response rate [ORR], progression-free survival [PFS] and overall survival [OS]) as well as safety (treatment-emergent adverse effects (grade ≥3) of neutropenia, infection, and any grade of serious treatment-emergent adverse effects) was evaluated. In the t(11;14)-positive subpopulation, venetoclax exposure relationships to PFS and OS indicated a trend of longer PFS and OS with higher exposures. Moreover, logistic regression analyses for clinical response (ORR and ≥VGPR rate) demonstrated a statistically significant (p < 0.05) relationship with exposure. Evaluation of the exposure-safety relationships demonstrated a lack of a relationship between venetoclax exposures (AUCavg ) and grade ≥3 infections, grade ≥3 neutropenia, grade ≥3 treatment-emergent adverse events or any grade serious treatment-emergent adverse events. These findings support further study of venetoclax at 800 mg QD dose in combination with dexamethasone in the t(11;14)-positive patient population where increased efficacy was observed without an increase in safety events.Clinical Trial: NCT01794520 registered 20 February 2013.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Mieloma Múltiplo , Neutropenia , Sulfonamidas , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/etiologia , Resultado do Tratamento , Biomarcadores , Neutropenia/induzido quimicamente , Dexametasona , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
2.
Int J Clin Oncol ; 29(2): 232-240, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38157190

RESUMO

BACKGROUND: Despite high response rates to initial therapy, most patients with mantle cell lymphoma (MCL) experience relapsed or refractory (R/R) disease. Here, we report the efficacy, safety, and pharmacokinetics of the Phase 2, single-arm M20-075 study (NCT04477486) of ibrutinib and venetoclax combination therapy in Japanese patients with R/R MCL. METHODS: Patients received 560 mg ibrutinib and 400 mg venetoclax (after a 5-week ramp-up from 20 mg) once daily for up to 104 weeks. Primary endpoint was complete response (CR) rate by independent review committee (IRC). Secondary endpoints included overall response rate (ORR), duration of response (DOR), undetectable minimal residual disease (uMRD) rate, progression-free survival (PFS), overall survival (OS), safety including dose-limiting toxicity (DLT) assessment in the first six patients, and pharmacokinetic parameters. Full analysis set (FAS) comprised all treated patients. Per protocol set (PPS) excluded treated patients with non-evaluable disease at baseline by IRC. RESULTS: Thirteen patients were treated (FAS n = 13; PPS, n = 12). Median age was 71 years, patients had a median of two prior treatments. After a median follow-up of 9.6 months, IRC-assessed CR rate and ORR were both 83% (PPS). All six MRD-evaluable patients had uMRD. Median DOR, PFS, and OS were unreached. The most common Grade ≥ 3 treatment-emergent adverse event (TEAE) was neutropenia (23%); 1 patient discontinued due to squamous cell carcinoma of the lung. No DLTs, tumor lysis syndrome, or deaths related to TEAEs were observed. CONCLUSION: Ibrutinib plus venetoclax exhibited high response rates and a well-tolerated safety profile in Japanese patients with R/R MCL.


Assuntos
Adenina/análogos & derivados , Compostos Bicíclicos Heterocíclicos com Pontes , Linfoma de Célula do Manto , Sulfonamidas , Adulto , Humanos , Idoso , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/patologia , Japão , Piperidinas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
3.
Radiat Environ Biophys ; 62(2): 235-251, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36939894

RESUMO

PbO (lead oxide) particles with different sizes were incorporated into polystyrene (PS) with various weight fractions (0, 10, 15, 25, 35%). These novel PS/PbO nano-composites were produced by roll mill mixing and compressing molding techniques and then investigated for radiation attenuation of X-rays (N-series/ISO 4037) typically used in radiology. Properties of the PbO particles were studied by X-ray diffraction (XRD). Filler dispersion and elemental composition of the prepared nano-composites were characterized using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), revealing better filler distribution and fewer agglomerations with smaller PbO particle size. Linear and mass attenuation coefficients (µ and µm), total molecular and atomic cross-sections (σmol and σatm), as well as effective atomic number and electron density (Zeff and Neff), were calculated for the energy range N40 to N200. The influence of PbO weight percentage on the enhancement of the shielding parameters of the nano-composites was expected; however, the effect of PbO particle size was surprising. Linear and mass attenuation coefficients for PS/PbO composites increased gradually with increasing PbO concentrations, and composites with a small size of nanoparticles showed best performance. In addition, increasing PbO concentration raised the effective atomic number Zeff of the composite. Hence, the electron density Neff increased, which provided a higher total interaction cross-section of X-rays with the composites. Maximum radiation shielding was observed for PS/PbO(B). It is concluded that this material might be used in developping low-cost and lightweight X-ray shielding to be used in radiology.


Assuntos
Nanopartículas , Proteção Radiológica , Raios X , Poliestirenos , Proteção Radiológica/métodos , Nanopartículas/química , Microscopia Eletrônica de Varredura
4.
Sensors (Basel) ; 21(6)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810187

RESUMO

Power transformers are considered important and expensive items in electrical power networks. In this regard, the early discovery of potential faults in transformers considering datasets collected from diverse sensors can guarantee the continuous operation of electrical systems. Indeed, the discontinuity of these transformers is expensive and can lead to excessive economic losses for the power utilities. Dissolved gas analysis (DGA), as well as partial discharge (PD) tests considering different intelligent sensors for the measurement process, are used as diagnostic techniques for detecting the oil insulation level. This paper includes two parts; the first part is about the integration among the diagnosis results of recognized dissolved gas analysis techniques, in this part, the proposed techniques are classified into four techniques. The integration between the different DGA techniques not only improves the oil fault condition monitoring but also overcomes the individual weakness, and this positive feature is proved by using 532 samples from the Egyptian Electricity Transmission Company (EETC). The second part overview the experimental setup for (66/11.86 kV-40 MVA) power transformer which exists in the Egyptian Electricity Transmission Company (EETC), the first section in this part analyzes the dissolved gases concentricity for many samples, and the second section illustrates the measurement of PD particularly in this case study. The results demonstrate that precise interpretation of oil transformers can be provided to system operators, thanks to the combination of the most appropriate techniques.

5.
Environ Chem Lett ; 19(3): 2057-2090, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33558806

RESUMO

The rising use of radioactive elements is increasing radioactive pollution and calling for advanced materials to protect individuals. For instance, polymers are promising due to their mechanical, electrical, thermal, and multifunctional properties. Moreover, composites made of polymers and high atomic number fillers should allow to obtain material with low-weight, good flexibility, and good processability. Here we review the synthesis of polymer materials for radiation protection, with focus on the role of the nanofillers. We discuss the effectivness of polymeric materials for the absorption of fast neutrons. We also present the recycling of polymers into composites.

6.
J Mol Evol ; 88(2): 151-163, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31820048

RESUMO

This study reports the evolutionary history and in-silico functional characterization of a novel water-deficit and ABA-responsive gene in wheat. This gene has remote sequence similarity to known abiotic stress-related genes in different plants, including CAP160 in Spinacia oleracea, RD29B in Arabidopsis thaliana, and CDeT11-24 in Craterostigma plantagineum. The study investigated if these genes form a close homologous relationship or if they are a result of convergent evolutionary processes. The results indicated a closely shared homologous relationship between these genes. Bayesian phylogenetic analysis of the protein sequences of the remotely related CAP160 proteins from various plant species indicated the presence of three distinct clades. Further analyses indicated that CAP160 homologous genes have predominantly evolved through neutral processes, with multiple regions experiencing signatures of purifying selection, while others were indicated to be the result of episodic diversifying selection events. Functional predictions revealed that these genes might share at least two functions related to abiotic stress conditions: one similar to the cryoprotective function of LEA protein, and the other a signalling molecule with phosphatidic acid binding specificity. Studies focused on the identification of cold-responsive genes are essential for the development of cold-tolerant crop plants, if we are to increase agricultural productivity throughout temperate regions.


Assuntos
Evolução Molecular , Genes de Plantas , Estresse Fisiológico , Triticum/genética , Arabidopsis , Teorema de Bayes , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Seleção Genética , Spinacia oleracea
7.
Invest New Drugs ; 38(5): 1400-1410, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31953695

RESUMO

Upregulation of Notch pathway is associated with poor prognosis in breast cancer. We present the results of a phase I study of an oral selective gamma secretase (GS) inhibitor (critical to Notch signaling), RO4929097 in combination with neoadjuvant chemotherapy for operable triple negative breast cancer. The primary objective was to determine the maximum tolerated dose (MTD) of RO4929097. Secondary objectives were to determine real-time pharmacokinetics of RO4929097 and paclitaxel, safety and pathologic (pCR) complete response to study treatment. Eligible patients, initiated carboplatin at AUC 6 administered intravenously (IV) on day 1, weekly paclitaxel at 80 mg/m2 IV and RO4929097 10 mg daily given orally (PO) on days 1-3, 8-10 and 15-17 for six 21-day cycles. RO4929097 was escalated in 10 mg increments using the 3 + 3 dose escalation design. Two DLTs were observed in 14 patients - Grade (G) 4 thrombocytopenia in dose level 1 (10 mg) and G3 hypertension in dose level 2 (20 mg). Protocol-defined MTD was not determined due to discontinuation of RO4929097 development. However, 4 of 5 patients enrolled to 20 mg dose of RO4929097 required dose reduction to 10 mg due to toxicities (including neutropenia, thrombocytopenia and hypertension) occurring during and beyond the DLT observation period. Thus, 10 mg would have been the likely dose level for further development. G3 or higher hematologic toxicities included neutropenia (N = 8, 57%) and thrombocytopenia (N = 5, 36%) patients. Six (43%) patients had G2-3 neuropathy requiring paclitaxel dose reduction. No signs of drug-drug interaction between paclitaxel and RO4929097 were evident. Five patients (36%) had pCR.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzazepinas/uso terapêutico , Carboplatina/uso terapêutico , Paclitaxel/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Administração Oral , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Benzazepinas/efeitos adversos , Benzazepinas/sangue , Benzazepinas/farmacocinética , Carboplatina/efeitos adversos , Feminino , Humanos , Infusões Intravenosas , Pessoa de Meia-Idade , Terapia Neoadjuvante , Paclitaxel/efeitos adversos , Paclitaxel/sangue , Paclitaxel/farmacocinética , Resultado do Tratamento
8.
BMC Infect Dis ; 20(1): 777, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076848

RESUMO

BACKGROUND: There are limited data on Coronavirus Disease 2019 (COVID-19) outcomes at a national level, and none after 60 days of follow up. The aim of this study was to describe national, 60-day all-cause mortality associated with COVID-19, and to identify risk factors associated with admission to an intensive care unit (ICU). METHODS: This was a retrospective cohort study including the first consecutive 5000 patients with COVID-19 in Qatar who completed 60 days of follow up by June 17, 2020. The primary outcome was all-cause mortality at 60 days after COVID-19 diagnosis. In addition, we explored risk factors for admission to ICU. RESULTS: Included patients were diagnosed with COVID-19 between February 28 and April 17, 2020. The majority (4436, 88.7%) were males and the median age was 35 years [interquartile range (IQR) 28-43]. By 60 days after COVID-19 diagnosis, 14 patients (0.28%) had died, 10 (0.2%) were still in hospital, and two (0.04%) were still in ICU. Fatal COVID-19 cases had a median age of 59.5 years (IQR 55.8-68), and were mostly males (13, 92.9%). All included pregnant women (26, 0.5%), children (131, 2.6%), and healthcare workers (135, 2.7%) were alive and not hospitalized at the end of follow up. A total of 1424 patients (28.5%) required hospitalization, out of which 108 (7.6%) were admitted to ICU. Most frequent co-morbidities in hospitalized adults were diabetes (23.2%), and hypertension (20.7%). Multivariable logistic regression showed that older age [adjusted odds ratio (aOR) 1.041, 95% confidence interval (CI) 1.022-1.061 per year increase; P < 0.001], male sex (aOR 4.375, 95% CI 1.964-9.744; P < 0.001), diabetes (aOR 1.698, 95% CI 1.050-2.746; P 0.031), chronic kidney disease (aOR 3.590, 95% CI 1.596-8.079, P 0.002), and higher BMI (aOR 1.067, 95% CI 1.027-1.108 per unit increase; P 0.001), were all independently associated with increased risk of ICU admission. CONCLUSIONS: In a relatively younger national cohort with a low co-morbidity burden, COVID-19 was associated with low all-cause mortality. Independent risk factors for ICU admission included older age, male sex, higher BMI, and co-existing diabetes or chronic kidney disease.


Assuntos
Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Adolescente , Adulto , Idoso , Betacoronavirus , COVID-19 , Criança , Estudos de Coortes , Infecções por Coronavirus/epidemiologia , Feminino , Hospitalização , Humanos , Unidades de Terapia Intensiva , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pandemias , Pneumonia Viral/epidemiologia , Gravidez , Complicações Infecciosas na Gravidez , Catar/epidemiologia , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Adulto Jovem
9.
Plant Physiol ; 176(3): 2376-2394, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29259104

RESUMO

Cold acclimation and winter survival in cereal species is determined by complicated environmentally regulated gene expression. However, studies investigating these complex cold responses are mostly conducted in controlled environments that only consider the responses to single environmental variables. In this study, we have comprehensively profiled global transcriptional responses in crowns of field-grown spring and winter wheat (Triticum aestivum) genotypes and their near-isogenic lines with the VRN-A1 alleles swapped. This in-depth analysis revealed multiple signaling, interactive pathways that influence cold tolerance and phenological development to optimize plant growth and development in preparation for a wide range of over-winter stresses. Investigation of genetic differences at the VRN-A1 locus revealed that a vernalization requirement maintained a higher level of cold response pathways while VRN-A1 genetically promoted floral development. Our results also demonstrated the influence of genetic background on the expression of cold and flowering pathways. The link between delayed shoot apex development and the induction of cold tolerance was reflected by the gradual up-regulation of abscisic acid-dependent and C-REPEAT-BINDING FACTOR pathways. This was accompanied by the down-regulation of key genes involved in meristem development as the autumn progressed. The chromosome location of differentially expressed genes between the winter and spring wheat genetic backgrounds showed a striking pattern of biased gene expression on chromosomes 6A and 6D, indicating a transcriptional regulation at the genome level. This finding adds to the complexity of the genetic cascades and gene interactions that determine the evolutionary patterns of both phenological development and cold tolerance traits in wheat.


Assuntos
Aclimatação/genética , Regulação da Expressão Gênica de Plantas , Triticum/fisiologia , Alelos , Parede Celular/genética , Parede Celular/metabolismo , Cromossomos de Plantas , Análise por Conglomerados , Resposta ao Choque Frio/genética , Flores/genética , Perfilação da Expressão Gênica , Genótipo , Redes e Vias Metabólicas/genética , Polimorfismo Genético , Saskatchewan , Triticum/genética , Triticum/crescimento & desenvolvimento
10.
J Clin Densitom ; 22(3): 382-390, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30292570

RESUMO

One of the best methods for diagnosing bone disease in humans is site-specific and total bone mineral density (BMD) measurements by Dual-energy X-ray Absorptiometry (DXA) machines. The basic disadvantage of this technology is inconsistent BMD measurements among different DXA machines from different manufacturers due to different image analysis algorithms. The objective of the present study was to apply artificial neural networks (ANNs) to estimate total BMD for diagnosing a population of Egyptians with and without pathology, using extracted features from DXA-DICOM images based on the Histogram and Binary algorithms as compared to reference BMD measurements by DXA machine. The sample size comprised 3000 male and female participants with an age range 22-49 years, who were referred to us for diagnosis and/or treatment and for DXA total body scans in the period from January 2016 till December 2017. We constructed an entry computer data-logging visible unit, where we applied morphological operations to get a specific bone image, and used their extracted feature vectors as inputs to ANNs with cascade training, gathering, and testing for DXA-DICOM image processing. The multilayer feed-forward ANN set up its initial weights, carried out training and initiated the recall mode, and finally observed its decision and interaction based on estimated BMD. The ANN construction was carried out using a 3-layer architecture, with one hidden layer of 85 neurons. The input layer has neuron numbers equal to 256 for the Histogram and 77,365 for Binary algorithms, respectively. Total BMD estimation performance based on the Binary algorithm was capable of identifying all DXA-DICOM images with an accuracy of 100% for the training, cross-validation, and testing of the ANN phases. We believe this strategy will represent the means for standardizing bone measurements of all DXA machines, regardless of the manufacturer.


Assuntos
Absorciometria de Fóton/métodos , Densidade Óssea , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Osteoporose/diagnóstico por imagem , Absorciometria de Fóton/instrumentação , Adulto , Algoritmos , Estudos de Casos e Controles , Egito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
J Appl Biomed ; 17(1): 67, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34907748

RESUMO

Lung cancer (LC) incidence represents 11.5% of all new cancers, resulting in 1.72 million deaths worldwide in 2015. With the aim to investigate the capability of the electronic nose (e-nose) technology for detecting and differentiating complex mixtures of volatile organic compounds in biofluids ex-vivo, we enrolled 50 patients with suspected LC and 50 matching controls. Tissue biopsy was taken from suspicious lung mass for histopathological evaluation and blood, exhaled breath, and urine samples were collected from all participants and qualitatively processed using e-nose. Odor-print patterns were further analysed using the principal component analysis (PCA) and artificial neural network (ANN) analysis. Adenocarcinoma, non-small cell LC and squamous cell carcinoma were the predominant pathological types among LC patients. PCA cluster-plots showed a clear distinction between LC patients and controls for all biological samples; where the overall success ratios of classification for principal components #1 and #2 were: 95.46, 82.01, and 91.66% for blood, breath and urine samples, respectively. Moreover, ANN showed a better discrimination between LC patients and controls with success ratios of 95.74, 91.67 and 100% for blood, breath and urine samples, respectively. The e-nose is an easy noninvasive tool, capable of identifying LC patients from controls with great precision.

12.
Biochem Biophys Res Commun ; 487(3): 709-715, 2017 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-28442344

RESUMO

CD44 and miR-221 are upregulated in hepatocellular carcinoma (HCC) cell lines and tumors, however a connection between the two has not been identified. As the expression of miR-221 directly correlated with CD44 in HCC cells, we hypothesized that miR-221 may directly or indirectly regulate CD44 expression. Inhibition of miR-221 with antisense in Sk-Hep-1 or SNU-449 cell lines reduced CD44 protein expression while miR-221 mimic increased CD44 protein levels. miR-221 antisense did not alter the CD44 mRNA levels in Sk-Hep-1 or SNU-449 cells suggesting that regulation of CD44 protein occurs post transcriptionally. To discover miRNAs that may be involved in the miR-221 regulation of CD44, we performed miRNA profiling in SNU-449 cells treated with anti-miR-221. Several miRNAs were increased with miR-221 inhibition including miR-708-5p, a miRNA that targets CD44. As miR-221 targets several regulators of the PI3K-AKT-mTOR pathway and a link between this pathway and CD44 has been previously shown in prostate cancer, we considered miR-221 regulation of CD44 may be through this pathway. Inhibition of miR-221 reduced p-4EBP1, a downstream effector of the PI3K-AKT-mTOR pathway. Likewise, inhibiting the PI3K-AKT-mTOR pathway with the ATP-competitive mTOR inhibitor PP242 reduced CD44 protein in SNU-423 and SNU-449 cells without altering CD44 mRNA levels.


Assuntos
Carcinoma Hepatocelular/metabolismo , Receptores de Hialuronatos/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Transdução de Sinais
13.
Pharm Res ; 34(5): 1053-1066, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28315083

RESUMO

Extracellular vesicles (EVs) represent a class of cell secreted organelles which naturally contain biomolecular cargo such as miRNA, mRNA and proteins. EVs mediate intercellular communication, enabling the transfer of functional nucleic acids from the cell of origin to the recipient cells. In addition, EVs make an attractive delivery vehicle for therapeutics owing to their increased stability in circulation, biocompatibility, low immunogenicity and toxicity profiles. EVs can also be engineered to display targeting moieties on their surfaces which enables targeting to desired tissues, organs or cells. While much has been learned on the role of EVs as cell communicators, the field of therapeutic EV application is currently under development. Critical to the future success of EV delivery system is the description of methods by which therapeutics can be successfully and efficiently loaded within the EVs. Two methods of loading of EVs with therapeutic cargo exist, endogenous and exogenous loading. We have therefore focused this review on describing the various published approaches for loading EVs with therapeutics.


Assuntos
Produtos Biológicos/química , Vesículas Extracelulares/química , Animais , Materiais Biocompatíveis/química , Transporte Biológico/efeitos dos fármacos , Comunicação Celular , Sistemas de Liberação de Medicamentos/métodos , Humanos
14.
BMC Genomics ; 16: 339, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25903161

RESUMO

BACKGROUND: Wheat is a major staple crop with broad adaptability to a wide range of environmental conditions. This adaptability involves several stress and developmentally responsive genes, in which microRNAs (miRNAs) have emerged as important regulatory factors. However, the currently used approaches to identify miRNAs in this polyploid complex system focus on conserved and highly expressed miRNAs avoiding regularly those that are often lineage-specific, condition-specific, or appeared recently in evolution. In addition, many environmental and biological factors affecting miRNA expression were not yet considered, resulting still in an incomplete repertoire of wheat miRNAs. RESULTS: We developed a conservation-independent technique based on an integrative approach that combines machine learning, bioinformatic tools, biological insights of known miRNA expression profiles and universal criteria of plant miRNAs to identify miRNAs with more confidence. The developed pipeline can potentially identify novel wheat miRNAs that share features common to several species or that are species specific or clade specific. It allowed the discovery of 199 miRNA candidates associated with different abiotic stresses and development stages. We also highlight from the raw data 267 miRNAs conserved with 43 miRBase families. The predicted miRNAs are highly associated with abiotic stress responses, tolerance and development. GO enrichment analysis showed that they may play biological and physiological roles associated with cold, salt and aluminum (Al) through auxin signaling pathways, regulation of gene expression, ubiquitination, transport, carbohydrates, gibberellins, lipid, glutathione and secondary metabolism, photosynthesis, as well as floral transition and flowering. CONCLUSION: This approach provides a broad repertoire of hexaploid wheat miRNAs associated with abiotic stress responses, tolerance and development. These valuable resources of expressed wheat miRNAs will help in elucidating the regulatory mechanisms involved in freezing and Al responses and tolerance mechanisms as well as for development and flowering. In the long term, it may help in breeding stress tolerant plants.


Assuntos
Biologia Computacional/métodos , MicroRNAs/análise , RNA de Plantas/análise , Triticum/crescimento & desenvolvimento , Triticum/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Aprendizado de Máquina , Poliploidia , Especificidade da Espécie , Estresse Fisiológico
15.
J Exp Bot ; 65(9): 2271-86, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24683181

RESUMO

The einkorn wheat mutant mvp-1 (maintained vegetative phase 1) has a non-flowering phenotype caused by deletions including, but not limited to, the genes CYS, PHYC, and VRN1. However, the impact of these deletions on global gene expression is still unknown. Transcriptome analysis showed that these deletions caused the upregulation of several pathogenesis-related (PR) and jasmonate-responsive genes. These results suggest that jasmonates may be involved in flowering and vernalization in wheat. To test this hypothesis, jasmonic acid (JA) and methyl jasmonate (MeJA) content in mvp and wild-type plants was measured. The content of JA was comparable in all plants, whereas the content of MeJA was higher by more than 6-fold in mvp plants. The accumulation of MeJA was also observed in vernalization-sensitive hexaploid winter wheat during cold exposure. This accumulation declined rapidly once plants were deacclimated under floral-inductive growth conditions. This suggests that MeJA may have a role in floral transition. To confirm this result, we treated vernalization-insensitive spring wheat with MeJA. The treatment delayed flowering with significant downregulation of both TaVRN1 and TaFT1 genes. These data suggest a role for MeJA in modulating vernalization and flowering time in wheat.


Assuntos
Acetatos/metabolismo , Ciclopentanos/metabolismo , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Oxilipinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Triticum/genética , Temperatura Baixa , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Plantas/metabolismo , Estações do Ano , Transcrição Gênica , Triticum/metabolismo
16.
Plant Cell Physiol ; 54(11): 1751-68, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23969557

RESUMO

This study compared the photosynthetic performance and the global gene expression of the winter hardy wheat Triticum aestivum cv Norstar grown under non-acclimated (NA) or cold-acclimated (CA) conditions at either ambient CO2 or elevated CO2. CA Norstar maintained comparable light-saturated and CO2-saturated rates of photosynthesis but lower quantum requirements for PSII and non-photochemical quenching relative to NA plants even at elevated CO2. Neither NA nor CA plants were sensitive to feedback inhibition of photosynthesis at elevated CO2. Global gene expression using microarray combined with bioinformatics analysis revealed that genes affected by elevated CO2 were three times higher in NA (1,022 genes) compared with CA (372 genes) Norstar. The most striking effect was the down-regulation of genes involved in the plant defense responses in NA Norstar. In contrast, cold acclimation reversed this down-regulation due to the cold induction of genes involved in plant pathogenesis resistance; and cellular and chloroplast protection. These results suggest that elevated CO2 has less impact on plant performance and productivity in cold-adapted winter hardy plants in the northern climates compared with warmer environments. Selection for cereal cultivars with constitutively higher expression of biotic stress defense genes may be necessary under elevated CO2 during the warm growth period and in warmer climates.


Assuntos
Dióxido de Carbono/farmacologia , Regulação da Expressão Gênica de Plantas , Fotossíntese , Triticum/fisiologia , Aclimatação , Regulação para Baixo , Perfilação da Expressão Gênica , Luz , Análise de Sequência com Séries de Oligonucleotídeos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/genética , Transpiração Vegetal , Estações do Ano , Estresse Fisiológico , Temperatura , Transcriptoma , Triticum/efeitos dos fármacos , Triticum/genética , Triticum/efeitos da radiação , Regulação para Cima
17.
Appl Radiat Isot ; 197: 110790, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37037134

RESUMO

High-density polyethylene (HDPE) was obtained through a compression molding technique, and incorporated with different filler weight fractions (0, 10, 15, 25, and 35%) of bulk WO3, and two different WO3 nanoparticle sizes (45 nm and 24 nm). The radiation attenuation ability of the new category of polymer composite HDPE/WO3 was evaluated using gamma-ray energies ranging from 59.53 up to 1332.5keV of four radioactive sources 241Am, 133Ba, 137Cs, and 60Co. The mass attenuation coefficients µm, the total molecular cross-section σmol, the effective atomic cross-section σatom, the total electronic cross-section σel, the effective atomic number Zeff, electron density Neff, the half value layer (HVL), the tenth value layer (TVL), and the relaxation length were investigated. The obtained results of the gamma-ray attenuation parameters exhibited an outstanding influence of the size and weight fraction of WO3 filler on the gamma-ray shielding ability of the HDPE composite. A significant improvement was detected at low gamma-ray energies. The HVL of the synthesized HDPE composites is compared with that of pure lead as a conventional shielding material. HDPE composite filled with the smaller size of WO3 nanoparticle shows good improvement in the attenuation parameters, which suggests promising applications in radiation protection and gamma-ray shielding.

18.
Sci Rep ; 13(1): 7406, 2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37149689

RESUMO

Integrating various tools in targeting mineral deposits increases the chance of adequate detection and characterization of mineralization zones. Selecting a convenient dataset is a key for a precise geological and hydrothermal alteration mapping. Remote sensing and airborne geophysical data have proven their efficiency as tools for reliable mineral exploration. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Advanced land imager (ALI), Landsat 8 (L8), and Sentinel 2 data are widely-used data among various types of remote sensing images in resolving lithological and hydrothermal alteration mapping over the last two decades. ASTER is a well-established satellite in geological remote sensing with detailed Short-wave infrared (SWIR) range compared to visible and near-infrared region (VNIR) that controls iron-associated alteration detection. On contrary, ALI has excellent coverage of the VNIR area (6 bands), but does not possess the potentiality of ASTER for the SWIR and thermal regions. Landsat 8 is widely used and highly recommended for lithological and hydrothermal alteration mapping. The higher spatial (up to 10 m) resolution of Sentinel 2 MSI has preserved its role in producing accurate geological mapping. Notwithstanding the foregoing, implementing the four datasets in a single study is time-consuming. Thus, an important question when commencing an exploration project for hydrothermal alterations-related mineralization (orogenic mineral deposits in the current research) is: which dataset should be adopted to fulfill proper and adequate outputs? Here the four widely recommended datasets (ASTER, ALI, L8, and sentinel 2) have been tested by applying the widely-accepted techniques (false color combinations, band ratios, directed principal component analysis, and constrained energy minimization) for geological and hydrothermal alteration mapping of Gabal El Rukham-Gabal Mueilha district, Egypt. The study area is covered mainly by Neoproterozoic heterogeneous collection of ophiolitic components, island arc assemblage, intruded by enormous granitic rocks. Additionally, airborne magnetic and radiometric data were applied and compared with the remote sensing investigations for deciphering the structural and hydrothermal alteration patterns within the study area. The results demonstrated a different extent from one sensor to another, highlighting their varied efficacy in detecting hydrothermal alterations (mainly hydroxyl-bearing alterations and iron oxides). Moreover, the analysis of airborne magnetic and radiometric data showed hydrothermal alteration zones that are consistent with the detected alteration pattern. The coincidence between high magnetic anomalies, high values of the K/eTh ratio, and the resultant alterations confirm the real alteration anomalies. Over and above that, the remote sensing results and airborne geophysical indications were verified with fieldwork and petrographic investigations, and strongly recommend combining ASTER and Sentinel 2 results in further investigations. Based on the outputs of the current research, we expect better hydrothermal alteration delineation by adopting the current findings as they sharply narrow the zones to be further investigated via costly geophysical and geochemical methods in mineral exploration projects.

19.
J Cancer ; 14(7): 1151-1156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215448

RESUMO

Infiltration of malignant cells into the central nervous system in hematological malignancies correlates with poor clinical outcomes. Investigations into the penetration of venetoclax into the central nervous system have been limited. We report venetoclax pharmacokinetics in plasma and cerebrospinal fluid samples from a Phase 1 study in pediatric patients with relapsed or refractory malignancies that demonstrate venetoclax ability to cross into the central nervous system. Venetoclax was detected in cerebrospinal fluid (CSF) samples, with concentrations ranging from < 0.1 to 26 ng/mL (mean, 3.6 ng/mL) and a plasma:CSF ratio ranging from 44 to 1559 (mean, 385). Plasma:CSF ratios were comparable among patients with AML and ALL and no clear trend was observed in the ratios over the course of treatment. Moreover, improvement in central nervous system (CNS) involvement status was observed in patients who had measurable concentrations of venetoclax in the CSF. CNS resolution was observed for up to six months while on treatment. These findings highlight the potential role of venetoclax and provide the opportunity to further investigate its utility in improving clinical outcomes for patients with CNS complications.

20.
Leuk Lymphoma ; 64(13): 2091-2100, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37665178

RESUMO

Selinexor, an oral inhibitor of the nuclear transport protein Exportin-1, shows promising single-agent activity in clinical trials of relapsed/refractory (R/R) acute myeloid leukemia (AML) and preclinical synergy with topoisomerase (topo) IIα inhibitors. We conducted a phase 1, dose-escalation study of selinexor with mitoxantrone, etoposide, and cytarabine (MEC) in 23 patients aged < 60 years with R/R AML. Due to dose-limiting hyponatremia in 2 patients on dose level 2 (selinexor 40 mg/m2), the maximum tolerated dose was 30 mg/m2. The most common grade ≥ 3 treatment-related non-hematologic toxicities were febrile neutropenia, catheter-related infections, diarrhea, hyponatremia, and sepsis. The overall response rate was 43% with 6 patients (26%) achieving complete remission (CR), 2 (9%) with CR with incomplete count recovery, and 2 (9%) with a morphologic leukemia-free state. Seven of 10 responders proceeded to allogeneic stem cell transplantation. The combination of selinexor with MEC is a feasibile treatment option for patients with R/R AML.


Assuntos
Hiponatremia , Leucemia Mieloide Aguda , Adulto , Humanos , Hiponatremia/induzido quimicamente , Hiponatremia/tratamento farmacológico , Leucemia Mieloide Aguda/etiologia , Mitoxantrona/uso terapêutico , Etoposídeo/uso terapêutico , Citarabina/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Terapia de Salvação
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