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Limited efficacy for ibrutinib and venetoclax in T-prolymphocytic leukemia: results from a phase 2 international study. Blood Adv 2024; 8:842-845. [PMID: 38190628 PMCID: PMC10874748 DOI: 10.1182/bloodadvances.2023012248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 12/21/2023] [Indexed: 01/10/2024] Open
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Phase 2 study of ibrutinib plus venetoclax in Japanese patients with relapsed/refractory mantle cell lymphoma. Int J Clin Oncol 2024; 29:232-240. [PMID: 38157190 PMCID: PMC10808627 DOI: 10.1007/s10147-023-02443-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 11/13/2023] [Indexed: 01/03/2024]
Abstract
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.
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Venetoclax in biomarker-selected multiple myeloma patients: Impact of exposure on clinical efficacy and safety. Hematol Oncol 2024; 42:e3222. [PMID: 37740931 DOI: 10.1002/hon.3222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/25/2023]
Abstract
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.
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Multidisciplinary Management of Phyllodes Tumours and Breast Sarcoma: A Cross-sectional Survey of Clinical Practice across the UK and Ireland. Clin Oncol (R Coll Radiol) 2024; 36:e31-e39. [PMID: 38294995 DOI: 10.1016/j.clon.2023.10.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/26/2023] [Accepted: 10/17/2023] [Indexed: 02/02/2024]
Abstract
AIMS Phyllodes tumours and breast sarcomas are uncommon tumours and their rarity poses significant challenges in diagnosis and management. This cross-sectional study was conducted to evaluate the multidisciplinary clinical practice for these tumours across the UK and Ireland, with the aim of identifying gaps in knowledge and providing direction for establishing national guidelines. MATERIALS AND METHODS An international survey was adapted and circulated to breast and/or sarcoma surgeons and oncologists in the UK and Ireland through national organisations. Multidisciplinary team (MDT) responses were analysed anonymously. RESULTS Twenty-eight MDTs participated in this study, predominately from high-volume units (85.5%). Although only 43% of the surveyed units were part of a trust that holds a sarcoma MDT, 68% of units managed malignant phyllodes and angiosarcoma, whereas 64.5% managed soft-tissue sarcoma of the breast. Across all subtypes, axillary surgery was recommended by 14-21% of the MDTs and the most recommended resection margins for breast surgery were 'no tumour on ink' in benign phyllodes (39%) and 10 mm in the remaining subtypes (25-29%). Immediate breast reconstruction was supported by 11-18% of MDTs for breast sarcoma subtypes, whereas 36% and 32% advocated this approach in benign and borderline phyllodes tumours, respectively. Adjuvant radiotherapy and chemotherapy were recommended by up to 29% and 11% of the MDTs, respectively. CONCLUSION The results of this study demonstrate a wide variation in clinical practice across the surveyed MDTs. As only 28 MDTs participated in our study, with under-representation from low-volume units, our results might be an underestimation of the variability in practice across the UK and Ireland. This multi-institutional study sheds light on controversial aspects in the management of phyllodes tumours and breast sarcoma, identifies the need for national guidelines to inform best practice, and calls for the centralisation of the management of breast sarcoma within specialist centres.
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Toward the development of sensors for lung cancer: The adsorption of 1-propanol on hydrophobic zeolites. J Chem Phys 2023; 159:214712. [PMID: 38059548 DOI: 10.1063/5.0168230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 11/07/2023] [Indexed: 12/08/2023] Open
Abstract
A healthy breath is mainly composed of water, carbon dioxide, molecular nitrogen, and oxygen and it contains many species, in small quantities, which are related to the ambient atmosphere and the metabolism. The breath of a person affected by lung cancer presents a concentration of 1-propanol higher than usual. In this context, the development of specific sensors to detect 1-propanol from breath is of high interest. The amount of propanol usually detected on the breath is of few ppb; this small quantity is a handicap for a reliable diagnostic. This limitation can be overcome if the sensor is equipped with a pre-concentrator. Our studies aim to provide an efficient material playing this role. This will contribute to the development of reliable and easy to use lung cancer detectors. For this, we investigate the properties of a few hydrophobic porous materials (chabazite, silicalite-1, and dealuminated faujasite). Hydrophobic structures are used to avoid saturation of materials by the water present in the exhaled breath. Our experimental and simulation results suggest that silicalite -1 (MFI) is the most suitable structure to be used as a pre-concentrator.
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Electronic and electrocatalytic properties of PbTiO 3: unveiling the effect of strain and oxygen vacancy. Dalton Trans 2023; 52:11965-11980. [PMID: 37577968 DOI: 10.1039/d3dt01478a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
First-principles calculations based on density-functional theory have been used to investigate the effect of biaxial strain and oxygen vacancy on the electronic, photocatalytic, and electrocatalytic properties of PbTiO3 oxide. Our results show that PbTiO3 has a high exciton binding energy and a band gap that can be easily moderated with different strain regimes. From a reactivity viewpoint, the highly exothermic adsorption of hydrogen atoms in both pristine and strained PbTiO3 structures does not make it a potential electrocatalyst for the hydrogen evolution reaction. Fortunately, the presence of oxygen vacancies on the PbTiO3 surface induces moderate adsorption energies, making the reduced PbTiO3 suitable for hydrogen evolution reaction processes.
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Towards better delineation of hydrothermal alterations via multi-sensor remote sensing and airborne geophysical data. Sci Rep 2023; 13:7406. [PMID: 37149689 PMCID: PMC10164183 DOI: 10.1038/s41598-023-34531-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 05/03/2023] [Indexed: 05/08/2023] Open
Abstract
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.
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Venetoclax Penetrates the Blood Brain Barrier: A Pharmacokinetic Analysis in Pediatric Leukemia Patients. J Cancer 2023; 14:1151-1156. [PMID: 37215448 PMCID: PMC10197937 DOI: 10.7150/jca.81795] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 04/04/2023] [Indexed: 05/24/2023] Open
Abstract
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.
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Sustainable Flame-Retardant Flax Fabrics by Engineered Layer-by-Layer Surface Functionalization with Phytic Acid and Polyethylenimine. FIRE TECHNOLOGY 2023:1-19. [PMID: 37360675 PMCID: PMC10042673 DOI: 10.1007/s10694-023-01387-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 02/13/2023] [Indexed: 06/28/2023]
Abstract
New generation of mission-oriented fabrics meets advanced requirements; such as electrical conductivity, flame retardancy, and anti-bacterial properties. However, sustainability concerns still are on-demand in fabrication of multi-functional fabrics. In this work, we used a bio-based phosphorus molecule (phytic acid, PA) to reinforce flax fabrics against flame via layer-by-layer consecutive surface modification. First, the flax fabric was treated with PA. Then, polyethylenimine (PEI) was localized above it to create negative charges, and finally PA was deposited as top-layer. Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), and inductively-coupled plasma atomic emission spectrometry (ICP-AES) proved successful chemical treatment. Pyrolysis-combustion flow calorimetry (PCFC) showed significant drop by about 77% in the peak of heat release rate (pHRR) from 215 W/g for untreated to 50 W/g for treated flax fabric. Likewise, the total heat release (THR) decreased by more than three times from 11 to 3.2 kJ/g. Mechanical behavior of the treated flax fabric was completely different from untreated flax fabrics, changing from almost highly-strengthened behavior with short elongation at break to a rubber-like behavior with significantly higher elongation at break. Surface friction resistance was also improved, such that the abrasion resistance of the modified fabrics increased up to 30,000 rub cycles without rupture. Supplementary Information The online version contains supplementary material available at 10.1007/s10694-023-01387-7.
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1185TiP First-in-human phase I study of ABBV-637 as monotherapy and in combination in patients with relapsed and refractory solid tumors. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.07.1308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Bioavailability Evaluation of Venetoclax Lower-Strength Tablets and Oral Powder Formulations to Establish Interchangeability with the 100 mg Tablet. Clin Drug Investig 2022; 42:657-668. [PMID: 35829925 PMCID: PMC9338003 DOI: 10.1007/s40261-022-01172-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2022] [Indexed: 11/06/2022]
Abstract
Background and Objective Venetoclax is an approved BCL-2 inhibitor, currently under evaluation in different hematological malignancies in adult and pediatric populations. Venetoclax is available as 10, 50, and 100 mg tablets. To provide an alternative to patients who find taking the commonly prescribed 100 mg tablet a challenge, the interchangeability of lower-strength tablets with the 100 mg tablet was investigated. Additionally, newly developed oral suspension powder formulations to facilitate dosing in pediatrics were evaluated. Methods Pharmacokinetic data from 80 healthy female participants from three phase I studies were utilized to evaluate the bioavailability of (1) 10 and 50 mg tablets relative to a 100 mg tablet; (2) 0.72 and 7.2% (drug to total weight) oral powder formulations relative to the 100 mg tablet; and (3) oral powder formulations administered using different vehicles (apple juice, apple sauce, and yogurt) relative to water under fed conditions. Results Bioavailability assessments at a 100 mg dose of venetoclax demonstrated bioequivalence across the 10, 50, and 100 mg tablet strengths. Oral powder formulations met the bioequivalence criteria (0.80–1.25) with respect to area under the concentration–time curve to time of the last measurable concentration (AUCt) and to infinite time (AUC∞) but exhibited a slightly lower maximum plasma concentration (Cmax). Exposure–response analyses were utilized to demonstrate that the lower Cmax observed with the powder formulations is not clinically meaningful. The delivery vehicles tested did not affect the bioavailability of venetoclax oral powder formulations. Conclusions The smaller-sized tablets (10 and 50 mg) and the newly developed oral powder formulations of venetoclax can be used interchangeably with the 100 mg tablets to improve the patients’ experience, while maintaining adequate exposure. Clinical Trials Identifiers NCT01682616, 11 September 2012; NCT02005471, 9 December 2013; NCT02242942, 17 September 2014; NCT02203773, 30 July 2014; NCT02287233, 10 November 2014; NCT02993523, 15 December 2016; NCT03069352, 3 March 2017. Supplementary Information The online version contains supplementary material available at 10.1007/s40261-022-01172-4.
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Abstract 1257: Early blood uMRD correlates with improved PFS in patients with CLL. Cancer Res 2022. [DOI: 10.1158/1538-7445.am2022-1257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The approval of targeted therapies has greatly improved outcomes for patients (pts) with chronic lymphocytic leukemia (CLL) in both 1L and relapsed/refractory (R/R) settings. The use of long-term outcomes such as progression free survival (PFS) and overall survival (OS) to inform early drug development can extend timelines and delay approval of potentially beneficial novel treatments. Establishing correlations between short-term treatment effects and long-term outcomes could shorten development timelines. Minimal residual disease (MRD) is a sensitive indicator of disease burden, with achievement of undetectable MRD (uMRD: < 1 CLL in 10,000 leukocytes [10-4]) either during or at the end of therapy being prognostic of prolonged PFS and OS. Our current work explores correlations between PFS and earlier dynamic changes in lymphocyte counts and peripheral blood (PB) MRD as potential tools for guiding drug development decisions in CLL.
Data from five trials (NCT numbers 01328626, 01889186, 02141282, 02756611 (receiving Venetoclax monotherapy and primarily R/R CLL pts) and 01682616 (R/R CLL pts receiving venetoclax + rituximab therapy) were analyzed. PB MRD was quantified by either flow cytometry or next generation sequencing at various timepoints. Many of these pts had high risk features such as 17pDEL or prior BCRi therapy. The relationships between absolute lymphocyte count (ALC) and percent change in lymphocytes at 1, 3, 6, and 9 months (M) of treatment and PB MRD status were explored. Additionally, the relationship between PB MRD levels at 6±2 M and achievement of uMRD was assessed. Lastly, we evaluated the relationship between PB MRD status at different time points (6±2, 9 and 12 M) and PFS using Kaplan Meier plots.
Across the trials, 708 CLL pts were treated, with 496 pts having PB MRD assessments at any time on therapy. PB uMRD rate of the evaluable population was 47.6% (236/496). Analysis of pts with PB MRD assessments at ~6 M (6±2 M, n=310) demonstrated that achievement of uMRD correlated with improved PFS (with median PFS of 56 M compared to 26 M in pts who had detectable MRD, p=0.037). Moreover, pts with residual disease in the PB (> 10-4) at ~6 M and achieved uMRD later while on therapy had a significantly lower residual disease at this timepoint than pts who did not achieve uMRD (p<0.001). Pts with residual disease < 10-3 (<1 CLL cell/1,000 leukocytes) at ~6 M were more likely to demonstrate PB uMRD at 12 M (72% vs 6%, p<0.001) compared to pts with residual disease ≥10-3 at this assessment. Neither ALC or percent change in lymphocytes at 1, 3, 6, and 9 M of treatment correlated with PB uMRD.
In this R/R CLL population who received continuous dosing of venetoclax, uMRD at ~6 M correlated with PFS outcomes. Additionally, MRD levels at ~6 M of therapy correlated with uMRD at 12 M. These suggest that including PB MRD assessments at early timepoints may be a useful tool in assessing efficacy and informing RP2D decisions during the development of novel agents in this indication.
Citation Format: Ibrahim Y. Abdelgawad, Ahmed A. Suleiman, Brenda Chyla, Majd Ghanim, Ahmed H. Salem, Mohamed Badawi. Early blood uMRD correlates with improved PFS in patients with CLL [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1257.
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Layer-by-layer polymer deposited fabrics with superior flame retardancy and electrical conductivity. REACT FUNCT POLYM 2022. [DOI: 10.1016/j.reactfunctpolym.2022.105221] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Effect of PbO incorporation with different particle size on X-ray attenuation of polystyrene. NUCLEAR TECHNOLOGY AND RADIATION PROTECTION 2022. [DOI: 10.2298/ntrp2201018o] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Lead oxide (PbO) bulk and nanoparticles of two different sizes (A = 78 nm and
B = 54 nm) are incorporated separately into the polystyrene matrix at
various concentrations (0, 10, 15, 25, and 35 %) using roll mill mixing and
compressing molding techniques. The X-ray narrow-spectrum series (N-series
/ ISO 4037-1) is then used to investigate the radiation attenuation
capability of the novel polymer composite PS/PbO, as well as the effect of
varying PbO particle sizes on shielding performance. The filler dispersion
and chemical elemental analysis of the synthesized composite are
investigated using scanning electron microscopy and energy-dispersive
X-ray spectroscopy. To determine the mass attenuation coefficients ?m,
samples with various thicknesses of the synthesized composite are examined
using a range of X-ray energies, and the experimental data are compared to
theoretical values from NIST databases (XCOM and FFAST). The results
indicate that either increasing the filler weight percentage or, decreasing
the filler particle size, enhanced the attenuation parameters throughout all
energies. The composite containing the smallest nanosize of PbO exhibited
the maximum radiation shielding efficacy among all combinations and
therefore, might be used to develop low-cost and lightweight X-ray shields.
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Antisense oligonucleotides: absorption, distribution, metabolism, and excretion. Expert Opin Drug Metab Toxicol 2021; 17:1281-1292. [PMID: 34643122 DOI: 10.1080/17425255.2021.1992382] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
INTRODUCTION Antisense oligonucleotides (ASOs) have emerged as a promising novel drug modality that aims to address unmet medical needs. A record of six ASO drugs have been approved since 2016, and more candidates are in clinical development. ASOs are the most advanced class within the RNA-based therapeutics field. AREAS COVERED This review highlights the two major backbones that are currently used to build the most advanced ASO platforms - the phosphorodiamidate morpholino oligomers (PMOs) and the phosphorothioates (PSs). The absorption, distribution, metabolism, and excretion (ADME) properties of the PMO and PS platforms are discussed in detail. EXPERT OPINION Understanding the ADME properties of existing ASOs can foster further improvement of this cutting-edge therapy, thereby enabling researchers to safely develop ASO drugs and enhancing their ability to innovate. ABBREVIATIONS 2'-MOE, 2'-O-methoxyethyl; 2'PS, 2 modified PS; ADME, absorption, distribution, metabolism, and excretion; ASO, antisense oligonucleotide; AUC, area under the curve; BNA, bridged nucleic acid; CPP, cell-penetrating peptide; CMV, cytomegalovirus; CNS, central nervous system; CYP, cytochrome P; DDI, drug-drug interaction; DMD, Duchenne muscular dystrophy; FDA, Food and Drug Administration; GalNAc3, triantennary N-acetyl galactosamine; IT, intrathecal; IV, intravenous; LNA, locked nucleic acid; mRNA, messenger RNA; NA, not applicable; PBPK, physiologically based pharmacokinetics; PD, pharmacodynamic; PK, pharmacokinetic; PMO, phosphorodiamidate morpholino oligomer; PMOplus, PMOs with positionally specific positive molecular charges; PPMO, peptide-conjugated PMO; PS, phosphorothioate; SC, subcutaneous; siRNA, small-interfering RNA; SMA, spinal muscular atrophy.
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Abstract 641: Clinical assessment of the bioavailability of venetoclax tablet and powder formulations. Cancer Res 2021. [DOI: 10.1158/1538-7445.am2021-641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Venetoclax is a first in class BCL-2 inhibitor that is approved for treatment of CLL and AML. It is currently under evaluation in other indications in adult and pediatric populations. Venetoclax is available as 10 mg, 50 mg, and 100 mg film-coated tablets. While the 100 mg tablet is most commonly used, the smaller size of the lower strength tablets is preferred by patients experiencing difficulty swallowing large tablets. Moreover, two powder formulations for suspension (0.72% and 7.2%) to be mixed with delivery vehicles were developed. In this abstract we present data from clinical studies that evaluated the bioavailability of the different venetoclax formulations relative to the commercially available 100 mg tablet. Three open-label, single-dose, crossover bioavailability studies in healthy female subjects were conducted. The first study evaluated the bioavailability of the commercially available 10 and 50 mg tablets relative to the 100 mg tablet. Forty subjects received a 100 mg dose of venetoclax (1x100 mg tablet, 2x50 mg tablets or 10x10 mg tablets) at the start of each period after a low-fat breakfast. The second study evaluated the bioavailability of the two powder formulations relative to the 100 mg tablet. Sixteen subjects received a 100 mg dose of venetoclax (1x100 mg film-coated tablet; 100 mg 0.72% powder formulation; 100 mg 7.2% powder formulation; and 4x25 mg dispersible tablets for oral suspension used in the Phase 1 study) in each of the 4 periods after a high fat breakfast. The third study evaluated the bioavailability of the two powder formulations when administered with different dosing vehicles relative to water. Twenty-four subjects (12 per cohort) received 100 mg of venetoclax (0.72% powder formulation or the 7.2% powder formulation) with either water, apple juice, apple sauce or yogurt in each of the 4 periods after a moderate fat breakfast. Bioavailability assessment of the commercial tablets demonstrated that ten 10 mg tablets were bioequivalent to one 100 mg tablet, two 50 mg tablets were bioequivalent to one 100 mg tablet, and two 50 mg tablets were bioequivalent to ten 10 mg tablets. The two powder formulations for oral suspension (0.72% and 7.2%) met the bioequivalence criteria (0.80-1.25) to the commercial 100 mg tablet with respect to AUCt and AUC∞, but the lower bound of the 90% CI of the Cmax extended slightly below 0.80. The delivery vehicles (water, apple juice, apple sauce and yogurt) did not affect the bioavailability of venetoclax 0.72% or 7.2% oral suspensions
Citation Format: Mohamed Badawi, Bo Tong, Xin Chen, Tammy Palenski, Su Young Kim, Divya Samineni, David Hoffman, Rajeev Menon, Ahmed Hamed Salem. Clinical assessment of the bioavailability of venetoclax tablet and powder formulations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 641.
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Genetic variations in some Egyptian Zea mexicana genotypes based on RAPD and AFLP markers. JOURNAL OF BIOSCIENCE AND APPLIED RESEARCH 2021; 0:77-92. [DOI: 10.21608/jbaar.2021.177577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Thymol nanoemulsion promoted broiler chicken's growth, gastrointestinal barrier and bacterial community and conferred protection against Salmonella Typhimurium. Sci Rep 2021; 11:7742. [PMID: 33833292 PMCID: PMC8032708 DOI: 10.1038/s41598-021-86990-w] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 03/23/2021] [Indexed: 02/08/2023] Open
Abstract
The present study involved in vivo evaluation of the growth promoting effects of thymol and thymol nanoemulsion and their protection against Salmonella Typhimurium infection in broilers. One-day old 2400 chicks were randomly divided into eight groups; negative and positive control groups fed basal diet without additives and thymol and thymol nanoemulsion groups (0.25, 0.5 and 1% each). At d 23, all chicks except negative control were challenged with S. Typhimurium. Over the total growing period, birds fed 1% thymol nanoemulsion showed better growth performance even after S. Typhimurium challenge, which came parallel with upregulation of digestive enzyme genes (AMY2A, PNLIP and CCK). Additionally, higher levels of thymol nanoemulsion upregulated the expression of MUC-2, FABP2, IL-10, IgA and tight junction proteins genes and downregulated IL-2 and IL-6 genes expression. Moreover, 1% thymol nanoemulsion, and to lesser extent 0.5% thymol nanoemulsion and 1% thymol, corrected the histological alterations of cecum and liver postinfection. Finally, supplementation of 1% thymol, 0.5 and 1% thymol nanoemulsion led to increased Lactobacilli counts and decreased S. Typhimurium populations and downregulated invA gene expression postinfection. This first report of supplying thymol nanoemulsion in broiler diets proved that 1% nano-thymol is a potential growth promoting and antibacterial agent.
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Severe SARS-CoV-2 infection presenting with acute kidney injury and diabetic ketoacidosis complicated by pancreatitis in a 53-year man with hypertension. Clin Case Rep 2021; 9:1202-1206. [PMID: 33768811 PMCID: PMC7981639 DOI: 10.1002/ccr3.3731] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/12/2020] [Indexed: 01/08/2023] Open
Abstract
Severe COVID-19 infection is associated with significant stress and marked immune response that can affect many organs and precipitate DKA, pancreatitis, and acute renal injury, which might be permanent.
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Venetoclax and Navitoclax in Combination with Chemotherapy in Patients with Relapsed or Refractory Acute Lymphoblastic Leukemia and Lymphoblastic Lymphoma. Cancer Discov 2021; 11:1440-1453. [PMID: 33593877 DOI: 10.1158/2159-8290.cd-20-1465] [Citation(s) in RCA: 122] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 01/25/2021] [Accepted: 02/11/2021] [Indexed: 11/16/2022]
Abstract
Combining venetoclax, a selective BCL2 inhibitor, with low-dose navitoclax, a BCL-XL/BCL2 inhibitor, may allow targeting of both BCL2 and BCL-XL without dose-limiting thrombocytopenia associated with navitoclax monotherapy. The safety and preliminary efficacy of venetoclax with low-dose navitoclax and chemotherapy was assessed in this phase I dose-escalation study (NCT03181126) in pediatric and adult patients with relapsed/refractory (R/R) acute lymphoblastic leukemia or lymphoblastic lymphoma. Forty-seven patients received treatment. A recommended phase II dose of 50 mg navitoclax for adults and 25 mg for patients <45 kg with 400 mg adult-equivalent venetoclax was identified. Delayed hematopoietic recovery was the primary safety finding. The complete remission rate was 60%, including responses in patients who had previously received hematopoietic cell transplantation or immunotherapy. Thirteen patients (28%) proceeded to transplantation or CAR T-cell therapy on study. Venetoclax with navitoclax and chemotherapy was well tolerated and had promising efficacy in this heavily pretreated patient population. SIGNIFICANCE: In this phase I study, venetoclax with low-dose navitoclax and chemotherapy was well tolerated and had promising efficacy in patients with relapsed/refractory acute lymphoblastic leukemia or lymphoblastic lymphoma. Responses were observed in patients across histologic and genomic subtypes and in those who failed available therapies including stem cell transplant.See related commentary by Larkin and Byrd, p. 1324.This article is highlighted in the In This Issue feature, p. 1307.
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Sintering and deposition of homo- and heteronanoparticles of aluminum and nickel on aluminum (100) substrate. Chem Phys 2021. [DOI: 10.1016/j.chemphys.2020.111037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
BACKGROUND COVID-19 is a newly emerging disease that is not yet fully understood. It is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel virus that is easily transmitted from human to human through the respiratory route. Usually, it presents with fever, headache, fatigue accompanied by respiratory symptoms like cough and dyspnea, and other systemic involvements. Chronic lymphocytic leukemia (CLL) is a common lymphoproliferative neoplasm characterized by absolute lymphocytosis and demonstration of clonality unlike other causes of lymphocytosis. Patients with CLL are considered immunocompromised because of impaired humoral immunity (mainly) and cellular immunity. Therefore, they are vulnerable to various infections including COVID-19. Little is known about the COVID-19 infection when it unmasks CLL. CASE REPORT A 49-year-old man with no significant previous illnesses, and an unremarkable family history, presented with a moderate COVID-19 infection. He initially presented to the emergency department with fever and mild shortness of breath. A complete blood count showed a high white blood cell count with absolute lymphocytosis. Flow cytometry revealed the clonality of the lymphocytes confirming the diagnosis of CLL. Despite having CLL, he developed a moderate COVID-19 infection and recovered in a few days. To the best of our knowledge, this is the first report of CLL, which presented with a COVID-19 infection as the initial presentation. CONCLUSIONS Lymphocytosis is an unexpected finding in patients diagnosed with COVID-19 infection and the elevated lymphocytes may be indicative of other conditions. Secondary causes of lymphocytosis like malignancy or other infections should be considered in these cases.
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Early Intervention with Lenalidomide in Patients with High-risk Chronic Lymphocytic Leukemia. Clin Cancer Res 2020; 26:6187-6195. [PMID: 32958702 DOI: 10.1158/1078-0432.ccr-20-1280] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 06/24/2020] [Accepted: 09/16/2020] [Indexed: 11/16/2022]
Abstract
PURPOSE Infectious complications constitute a leading cause of morbidity and mortality in chronic lymphocytic leukemia (CLL). Patients respond poorly to vaccines, particularly pneumococcal polysaccharide and influenza vaccines. In addition, patients with genetically high-risk disease are at increased risk for early disease progression and death. Lenalidomide, an oral immunomodulatory agent with demonstrated clinical activity in CLL, can potentially restore immune system dysfunction associated with CLL while improving disease outcomes. PATIENTS AND METHODS Phase II study randomized 49 patients with genetically high-risk CLL or small lymphocytic lymphoma [SLL; defined as unmutated Ig heavy chain variable region, deletion(17p) or (11q), and/or complex abnormal karyotype], to receive lenalidomide either concurrent (arm A) or sequential to (arm B) two doses of 13-valent protein-conjugated pneumococcal vaccine (PCV13) administered 2 months apart, in patients not meeting International Workshop on Chronic Lymphocytic Leukemia treatment criteria. RESULTS Four serotypes (3, 4, 5, 6B) achieved the additional seroprotection definition of a fourfold increase in arm A, and six serotypes (3, 4, 5, 6B, 19A, 19F) in arm B. All patients achieved the defined concentration of 0.35 μg/mL for at least one serotype tested. No significant difference was observed with the addition of lenalidomide. At median time on treatment of 3.6 years, median progression-free survival (PFS) was 5.8 years [95% confidence interval (CI), 3.1-not reached]. PFS at 1, 2, and 3 years was 85% (95% CI, 72-93), 79% (95% CI, 64-88), and 72% (95% CI, 57-83), respectively. CONCLUSIONS Lenalidomide is efficacious with manageable toxicities as an early intervention strategy in patients with high-risk CLL, but did not enhance humoral response to PCV13 vaccine.
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Abstract
SARS-CoV-2 infection can present with various clinical features, among which gastrointestinal manifestations such as nausea, diarrhea, vomiting, and mild abdominal pain have been reported. Recognition of rare presentations of SARS-CoV-2 infection has increased over time. These atypical and rare presentations may lead to difficulties in establishing the diagnosis in a timely manner; furthermore, they may lead to unnecessary investigations, extended hospital stays, adverse outcomes, and more strain on healthcare resources. We present three cases admitted to our hospital with a picture that mimicked an acute abdomen, necessitating surgical assessment and evaluation. All cases turned out to be SARS-CoV-2 positive and did not require surgical management. We discuss the management course, highlight the importance of abdominal symptoms in the setting of COVID-19, and discuss the implications of this association for medical practice amid the current pandemic in both resource-rich and resource-limited settings.
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Imprinting isolated single iron atoms onto mesoporous silica by templating with metallosurfactants. J Colloid Interface Sci 2020; 573:193-203. [PMID: 32278950 DOI: 10.1016/j.jcis.2020.03.095] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/12/2020] [Accepted: 03/26/2020] [Indexed: 01/03/2023]
Abstract
HYPOTHESIS One of the main drawbacks of metal-supported materials, traditionally prepared by the impregnation of metal salts onto pre-synthesized porous supports, is the formation of large and unevenly dispersed particles. Generally, the larger are the particles, the lower is the number of catalytic sites. Maximum atom exposure can be reached within single-atom materials, which appear therefore as the next generation of porous catalysts. EXPERIMENTS Herein, we designed single iron atom-supported silica materials through sol-gel hydrothermal treatment using mixtures of a non-ionic surfactant (Pluronic P123) and a metallosurfactant (cetyltrimethylammoniumtrichloromonobromoferrate, CTAF) as porogens. The ratio between the Pluronic P123 and the CTAF enables to control the silica structural and textural properties. More importantly, CTAF acts as an iron source, which amount could be simply tuned by varying the non-ionic/metallo surfactants molar ratio. FINDINGS The fine distribution of iron atoms onto the silica mesopores results from the iron distribution within the mixed micelles, which serve as templates for the polymerization of the silica matrix. Several characterization methods were used to determine the structural and textural properties of the silica material (XRD, N2 sorption isotherms and TEM) and the homogeneous distribution and lack of clustering of iron atoms in the resulting materials (elemental analysis, magnetic measurements, pair distribution function (PDF), MAS-NMR and TEM mapping). The oxidation and spin state of single-iron atoms determined from their magnetic properties were confirmed by DFT calculations. This strategy might find straightforward applications in preparing versatile single atom catalysts, with improved efficiency compared to nanosized ones.
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Improved tribological properties, thermal and colloidal stability of poly-α-olefins based lubricants with hydrophobic MoS 2 submicron additives. J Colloid Interface Sci 2020; 562:91-101. [PMID: 31837623 DOI: 10.1016/j.jcis.2019.12.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 11/30/2019] [Accepted: 12/02/2019] [Indexed: 11/19/2022]
Abstract
HYPOTHESIS Newtonian liquids, usually used as base oil lubricants, exhibit low viscosity under extreme thermal conditions, needed for the functioning of wind turbines. This is directly affecting the colloidal stability and the tribological properties of the formulations containing additives, such as MoS2. Here, it was hypothesized that the surface hydrophobization of MoS2 particles will allow for an increased colloidal stability of the resulting formulations, for temperatures as high as 80 °C. EXPERIMENTS The antifriction properties and the thermal stability of the designed formulations were determined on submicron MoS2 particles dispersed in poly-α-olefins (PAO) base oils of different dynamic viscosities (from 32 to 1650 mPa·s at 25 °C). The submicron particles of MoS2 (300-500 nm in diameter) were synthesised by a simple one-pot solvothermal method under mild conditions. The resulting particles were hydrophobized in situ in PAO base oils using alkyltrichlorosilane grafting agents with two chain lengths (C8 and C18). FINDINGS The covalent grafting of alkylsilanes through Mo-O-Si bonds was confirmed by DFT calculations and FT-IR measurements. Turbiscan optical analysis revealed that thermal and colloidal stabilities can be significantly improved depending on oil viscosity and chain length of the grafting agent. The formulations in the PAO65 oil remained highly stable (TSI < 1), even at 80 °C. Herein, we demonstrate the impact of hydrophobization degree on the tribological properties of the lubricants, which, importantly, could reach ultra-low friction coefficients, less than 0.02.
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A phase I study of an oral selective gamma secretase (GS) inhibitor RO4929097 in combination with neoadjuvant paclitaxel and carboplatin in triple negative breast cancer. Invest New Drugs 2020; 38:1400-1410. [PMID: 31953695 DOI: 10.1007/s10637-020-00895-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 01/10/2020] [Indexed: 12/20/2022]
Abstract
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.
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Insights into the impact of Ivermectin on some protein aspects linked to Culex pipiens digestion and immunity. Parasitol Res 2019; 119:55-62. [DOI: 10.1007/s00436-019-06539-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 11/03/2019] [Indexed: 02/08/2023]
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Niemann-pick disease type C-1 (NP-C1): Case series of three patients and literature review. J Neurol Sci 2019. [DOI: 10.1016/j.jns.2019.10.1666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Treatable causes of hereditary ataxia: Cases and literature review. J Neurol Sci 2019. [DOI: 10.1016/j.jns.2019.10.1660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Letter to the Editor: Exposure-response or clearance-response relationship in immune checkpoint therapy?-A comment on 'correlation between nivolumab exposure and treatment outcomes in non-small-cell lung cancer' by Basak et al. Eur J Cancer 2019; 114:25-26. [PMID: 31009820 DOI: 10.1016/j.ejca.2019.02.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 02/18/2019] [Indexed: 10/27/2022]
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Adsorption of NO, NO2, CO, H2O and CO2 over isolated monovalent cations in faujasite zeolite: a periodic DFT investigation. Theor Chem Acc 2018. [DOI: 10.1007/s00214-018-2373-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Pharmacokinetic-Pharmacodynamic Model of Neutropenia in Patients With Myeloma Receiving High-Dose Melphalan for Autologous Stem Cell Transplant. CPT Pharmacometrics Syst Pharmacol 2018; 7:748-758. [PMID: 30343510 PMCID: PMC6263666 DOI: 10.1002/psp4.12345] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
High-dose melphalan (HDM) is part of the conditioning regimen in patients with multiple myeloma (MM) receiving autologous stem cell transplantation (ASCT). However, individual sensitivity to melphalan varies, and many patients experience severe toxicities. Prolonged severe neutropenia is one of the most severe toxicities and contributes to potentially life-threatening infections and failure of ASCT. Granulocyte-colony stimulating factor (G-CSF) is given to stimulate neutrophil proliferation after melphalan administration. The aim of this study was to develop a population pharmacokinetic/pharmacodynamic (PK/PD) model capable of predicting neutrophil kinetics in individual patients with MM undergoing ASCT with high-dose melphalan and G-CSF administration. The extended PK/PD model incorporated several covariates, including G-CSF regimen, stem cell dose, hematocrit, sex, creatinine clearance, p53 fold change, and race. The resulting model explained portions of interindividual variability in melphalan exposure, therapeutic effect, and feedback regulation of G-CSF on neutrophils, thus enabling simulation of various doses and prediction of neutropenia duration.
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Globally increased ultraconserved noncoding RNA expression in pancreatic adenocarcinoma. Oncotarget 2018; 7:53165-53177. [PMID: 27363020 PMCID: PMC5288176 DOI: 10.18632/oncotarget.10242] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 05/28/2016] [Indexed: 12/29/2022] Open
Abstract
Transcribed ultraconserved regions (T-UCRs) are a class of non-coding RNAs with 100% sequence conservation among human, rat and mouse genomes. T-UCRs are differentially expressed in several cancers, however their expression in pancreatic adenocarcinoma (PDAC) has not been studied. We used a qPCR array to profile all 481 T-UCRs in pancreatic cancer specimens, pancreatic cancer cell lines, during experimental pancreatic desmoplasia and in the pancreases of P48Cre/wt; KrasLSL-G12D/wt mice. Fourteen, 57 and 29% of the detectable T-UCRs were differentially expressed in the cell lines, human tumors and transgenic mouse pancreases, respectively. The vast majority of the differentially expressed T-UCRs had increased expression in the cancer. T-UCRs were monitored using an in vitro model of the desmoplastic reaction. Twenty-five % of the expressed T-UCRs were increased in the HPDE cells cultured on PANC-1 cellular matrix. UC.190, UC.233 and UC.270 were increased in all three human data sets. siRNA knockdown of each of these three T-UCRs reduced the proliferation of MIA PaCa-2 cells up to 60%. The expression pattern among many T-UCRs in the human and mouse pancreases closely correlated with one another, suggesting that groups of T-UCRs are co-activated in PDAC. Successful knockout of the transcription factor EGR1 in PANC-1 cells caused a reduction in the expression of a subset of T-UCRs suggesting that EGR1 may control T-UCR expression in PDAC. We report a global increase in expression of T-UCRs in both human and mouse PDAC. Commonalties in their expression pattern suggest a similar mechanism of transcriptional upregulation for T-UCRs in PDAC.
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Abstract 141: CD44 positive and sorafenib resistant hepatocellular carcinomas respond to the ATP-competitive mTOR inhibitor INK128. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The PI3K/AKT/mTOR pathway is activated in about 50% of patients with hepatocellular carcinoma (HCC). Allosteric mTOR inhibitors, also known as rapalogs, fail to show any significant clinical utility. In an effort to identify new pathways and compounds to treat advanced HCC, we considered the ATP-competitive mTOR inhibitor INK128. ATP-competitive mTOR inhibitors attenuate both mTORC1 and mTORC2. We evaluated INK128 in sorafenib sensitive and insensitive HCC cell lines, CD44low and CD44high HCC and those cell lines with acquired sorafenib resistance. CD44 was significantly increased in Huh7 cells made resistant to sorafenib. Forced expression of CD44 enhanced cellular proliferation and migration, and rendered the cells more sensitive to the anti-proliferative effects of INK128. INK128 suppressed CD44 expression by blocking phosphorylation of eukaryotic translation initiation factor 4EBP1 in HCC cells while allosteric mTOR inhibitors do not. Moreover, INK128 exhibited potent anti-proliferative and anti-migration effects on the mesenchymal-like HCC cells, CD44high and sorafenib resistant HCC cells compared to the allosteric mTOR inhibitor everolimus. Combination studies of INK128 and sorafenib showed an additive to synergistic anti-proliferative effect in CD44high HCC cells. Our findings suggest that ATP-competitive mTOR inhibitors are effective in treating advanced HCC patients who express CD44, and are insensitive or resistant to sorafenib. It also highlights the potential use of CD44 as a biomarker of response in these patients.
Citation Format: Mohamed Badawi, Jihye Kim, Dhruvitkumar Sutaria, Tasneem Motiwala, Ryan Reyes, Nissar Wani, Samson Jacob, Mitch Phelps, Thomas Schmittgen. CD44 positive and sorafenib resistant hepatocellular carcinomas respond to the ATP-competitive mTOR inhibitor INK128 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 141. doi:10.1158/1538-7445.AM2017-141
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Testing for HTLV 1 and HTLV 2 among blood donors in Western Saudi Arabia: prevalence and cost considerations. Transfus Med 2017; 28:60-64. [PMID: 28656665 DOI: 10.1111/tme.12440] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 06/05/2017] [Accepted: 06/06/2017] [Indexed: 01/18/2023]
Abstract
BACKGROUND Screening all blood donors for human T-cell lymphotropic viruses 1 and 2 (HTLV 1 and HTLV 2) is mandatory in Saudi Arabia. The aim of this study is to evaluate the results and costs associated with the current testing policy for HTLV 1 and HTLV 2 in blood donors at King Abdulaziz University Hospital (KAUH), Jeddah. STUDY DESIGNS AND METHODS Donor-testing results from Blood Transfusion Services at KAUH were reviewed over a 10-year period, from January 2006 through December 2015. All donors were screened using chemiluminescent microparticle immunoassay. Reactive samples were then tested by Western blot for confirmation. Costs associated with testing were calculated. RESULTS Data of 107 419 donations in the study period were reviewed. Saudi nationals constituted 51 168 donors (47·6%). Of 107 419 blood donors tested for HTLV 1 and HTLV 2 antibody, and 95 (0·088%) donors were reactive to screening tests. None of the samples found to be reactive to screening tests was positive by Western blot. The average cost of testing was US$ 171 870 per year. CONCLUSION No donors were confirmed to have HTLV 1 and HTLV 2 in this cohort exceeding 100 000 donors. We propose changes to the policy mandating universal testing by replacing it with universal leukodepletion coupled with targeted screening to donors coming from endemic area or donors at risk. Such changes are expected to lead to a reduction of testing cost without affecting safety.
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Research Note. One minute, intraoperative assessment of the viability of hydatid cysts using a simple reagent strip test. Helminthologia 2017; 54:157-164. [DOI: 10.1515/helm-2017-0020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023] Open
Abstract
Summary
The aim of the current work was to evaluate the possibility of using a rapid and simple reagent strip test to investigate the viability of hydatid cysts intraoperatively, via testing certain biochemical parameters. Thirty eight HCF samples were processed and examined by different methods for determining the viability status. Using the reagent strip test in the current study, the highest significant level of glucose was detected in HCF samples with the highest viability % at pH 7.5 and the lowest significant level of glucose was detected in HCF samples with the lowest viability % at pH 8.5, indicating a likely correlation between glucose concentration and the viability of PSs. On the contrary, protein was not detected in HCF containing viable PSs and was found to be higher in HCF containing non-viable PSs, denoting the possible degenerative processes in such PSs. Haemoglobin was found in trace amounts in all of our samples. In addition, the strip test detected bacterial contamination in 8 samples and biliary leakage in 7 samples. Our results suggest that the simple reagent strip test can assist in providing fast, uncomplicated primary data regarding the viability status of the hydatid cysts. Thus, it may aid the surgeons to make informed decisions for further management and appropriate follow up to minimise the risk of post-operative recurrence.
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Low active loading of cargo into engineered extracellular vesicles results in inefficient miRNA mimic delivery. J Extracell Vesicles 2017; 6:1333882. [PMID: 28717424 PMCID: PMC5505005 DOI: 10.1080/20013078.2017.1333882] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Indexed: 02/06/2023] Open
Abstract
Extracellular vesicles (EVs) hold great potential as novel systems for nucleic acid delivery due to their natural composition. Our goal was to load EVs with microRNA that are synthesized by the cells that produce the EVs. HEK293T cells were engineered to produce EVs expressing a lysosomal associated membrane, Lamp2a fusion protein. The gene encoding pre-miR-199a was inserted into an artificial intron of the Lamp2a fusion protein. The TAT peptide/HIV-1 transactivation response (TAR) RNA interacting peptide was exploited to enhance the EV loading of the pre-miR-199a containing a modified TAR RNA loop. Computational modeling demonstrated a stable interaction between the modified pre-miR-199a loop and TAT peptide. EMSA gel shift, recombinant Dicer processing and luciferase binding assays confirmed the binding, processing and functionality of the modified pre-miR-199a. The TAT-TAR interaction enhanced the loading of the miR-199a into EVs by 65-fold. Endogenously loaded EVs were ineffective at delivering active miR-199a-3p therapeutic to recipient SK-Hep1 cells. While the low degree of miRNA loading into EVs through this approach resulted in inefficient distribution of RNA cargo into recipient cells, the TAT TAR strategy to load miRNA into EVs may be valuable in other drug delivery approaches involving miRNA mimics or other hairpin containing RNAs.
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Comprehensive toxicity and immunogenicity studies reveal minimal effects in mice following sustained dosing of extracellular vesicles derived from HEK293T cells. J Extracell Vesicles 2017; 6:1324730. [PMID: 28717420 PMCID: PMC5505007 DOI: 10.1080/20013078.2017.1324730] [Citation(s) in RCA: 325] [Impact Index Per Article: 46.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Indexed: 02/07/2023] Open
Abstract
Extracellular vesicles (EVs) are under evaluation as therapeutics or as vehicles for drug delivery. Preclinical studies of EVs often use mice or other animal models to assess efficacy and disposition. However, as most EVs under evaluation are derived from human cells, they may elicit immune responses which may contribute to toxicities or enhanced EV clearance. Furthermore, EVs from different cell sources or EVs comprising various cargo may differ with respect to immunogenicity or toxicity. To assess EV-induced immune response and toxicity, we dosed C57BL/6 mice with EVs intravenously and intraperitoneally for 3 weeks. EVs were harvested from wild type or engineered HEK293T cells which were modified to produce EVs loaded with miR-199a-3p and chimeric proteins. Blood was collected to assess hematology, blood chemistry, and immune markers. Spleen cells were immunophenotyped, and tissues were harvested for gross necropsy and histopathological examination. No signs of toxicity were observed, and minimal evidence of changes in immune markers were noted in mice dosed with engineered, but not with wild type EVs. This study provides a framework for assessment of immunogenicity and toxicity that will be required as EVs from varying cell sources are tested within numerous animal models and eventually in humans.
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miR-221 regulates CD44 in hepatocellular carcinoma through the PI3K-AKT-mTOR pathway. Biochem Biophys Res Commun 2017; 487:709-715. [PMID: 28442344 DOI: 10.1016/j.bbrc.2017.04.121] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 04/22/2017] [Indexed: 01/15/2023]
Abstract
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.
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Achieving the Promise of Therapeutic Extracellular Vesicles: The Devil is in Details of Therapeutic Loading. Pharm Res 2017; 34:1053-1066. [PMID: 28315083 DOI: 10.1007/s11095-017-2123-5] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 02/13/2017] [Indexed: 12/18/2022]
Abstract
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.
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Thermodynamic and structural properties of binary calcium silicate glasses: insights from molecular dynamics. Phys Chem Chem Phys 2017; 19:19083-19093. [DOI: 10.1039/c7cp03397d] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The thermodynamic and structural properties of calcium-modified binary silicate glasses have been computed using molecular dynamics simulations.
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Response of Maize (Zea mays L.) to Moisture Stress under Different Nitrogen Fertilization Levels. JOURNAL OF SOIL SCIENCES AND AGRICULTURAL ENGINEERING 2016; 7:865-872. [DOI: 10.21608/jssae.2016.40487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Anti-invasion and anti-migration effects of miR-199a-3p in hepatocellular carcinoma are due in part to targeting CD151. Int J Oncol 2016; 49:2037-2045. [PMID: 27599545 DOI: 10.3892/ijo.2016.3677] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/13/2016] [Indexed: 12/12/2022] Open
Abstract
Several studies have reported reduced miR-199a-3p expression in hepatocellular carcinoma (HCC). In an effort to discover important target genes for miR-199a-3p that may be related to HCC development or progression, we identified the tetraspanin, transmembrane glycoprotein CD151. Luciferase reporter assays and western blotting identified CD151 as a bona fide miR-199a-3p target gene. While CD151 protein was increased in the mesenchymal but not the epithelial HCC cell lines, CD151 knockdown with siRNA did not reduce HCC cell proliferation in either group of cells. miR-199a-3p reduced in vitro invasion and migration of CD151-positive HCC cells. Examination of the mRNA and protein expression in pairs of primary HCC tumors and adjacent benign tissues showed that not only was CD151 mRNA and protein increased in the tumors but also that an inverse correlation exists between the miR-199a-3p and CD151 RNA expression. We report that CD151 is a target of miR-199a-3p and that increased CD151 protein resulting from reduced miR-199a-3p could contribute to the development of metastatic HCC.
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COMPUTED TOMOGRAPHY VERSUS PLAIN RADIOGRAM IN EVALUATION OF RESIDUAL STONES AFTER PERCUTANEOUS NEPHROLITHOTOMY OR PYELONEPHROLITHOTOMY FOR COMPLEX MULTIPLE AND BRANCHED KIDNEY STONES. ACTA ACUST UNITED AC 2015; 45:321-4. [PMID: 26485850 DOI: 10.12816/0017575] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
This study compared the efficacy of computed tomography of the urinary tract (CT urography) versus plain X-ray of the urinary tract (KUB) in detection and evaluation of the significance of residual stone after percutaneous nephrolithotripsy (PCNL) or surgical pyelonephrolithotomy (SPNL) for complex branching or multiple stones in the kidney. A retrospective prospective archival cohort of 168 patients underwent PCNL or SPNL for large stag horn or multiple stones in the kidney were evaluated, they were 113 patients who underwent SPNL, and 55 patients underwent PCNL. In all patients they had KUB second day of the operation, those who had multiple kidney punctures in the PCNL procedure for multiple stones, or multiple nephrotomies in the SPNL procedure, or had a radiolucent stones had an additional imaging with CT urography. Indications for the CT urography were cases of radiolucent stones and multiple small calyceal stones detected pre-operatively. The study was conducted between March 2010 and December 2014, data weie retrospectively analyzed. Preoperatively multiple or branching stones were diagnosed with intravenous urography and CT urography. Stone size and location were mapped pre-operatively on a real-size drawing, and three dimensional computed construction images in multiple planes. All patients were informed about the advantages, disadvantages and probable complications of both PCNL and SPNL before the selection of the procedure. Patients decided the type of the surgery type by themselves and written informed consent was obtained from all patients prior to the surgery. Patients were in two groups according to the patient's preference of surgery type. Group 1 consisted of 113 patients who underwent SPNL and Group 2 consisted of 55 patients treated with PCNL. Detection of residual stones stone postoperatively using KUB and CT urography was evaluated in both groups. There was statistical significance between the two imaging methodology in detection of residual stones after PCNL and/or SPNL. CT urography detected stones of 2 mm and up to 5mm which was not visualized with KUB. CT urography was statistically significant and precise in detecting the radiolucent stones of uric acid, urate, and phostate stones which were not detected by KUB.
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Urothelial carcinoma of the urinary bladder mixed with squamous differentiation or squamous cell carcinoma in areas with schistosomiasis is showing high risk of recurrence and poor survival. JOURNAL OF THE EGYPTIAN SOCIETY OF PARASITOLOGY 2014; 44:467-473. [PMID: 25597161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In schistosomiasis haematobium areas endemic, bladder cancer is the first cause of malignancy in men and fourth in women. The chronic schistosomiasis would lead to variant histologic patterns which manifest in squamous cell carcinoma (SCC) or squamous differentiation (SqD). This study evaluated the clinical outcome after radical cystectomy (RC) in patients with urothelial carcinoma (UC) mixed with SCC or SqD, Comparison was done with two arms of pure UC and pure SCC, indication for RC was muscle-invasive-disease, and evaluation included recurrence, metastases, and overall survival. The data of patients treated with RC for muscle-invasive-disease, selection was revised for 127 patients with urothelial carcinoma mixed with SCC/SqD, two comparative arms were 100 patients with pure UC, and 100 patients had pure SCC. Follow up was on 8 months, 3 years, and 5 years to detect recurrence, metastasis, and overall survival in the three groups. The results showed that by comparison of disease aggressiveness in the three groups regarding recurrence, metastasis, and overall survival was analysed. Overall survival with mixed tumours was significantly lower than pure UC or SCC, recurrence and metastases were higher in mixed tumour which was an independent factor for poor prognosis and low survival.
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Oral anticoagulation throughout pregnancy in patients with mechanical heart valve prosthesis: Safe alternatives. J Saudi Heart Assoc 2013. [DOI: 10.1016/j.jsha.2013.03.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Expression of vernalization responsive genes in wheat is associated with histone H3 trimethylation. Mol Genet Genomics 2012; 287:575-90. [PMID: 22684814 DOI: 10.1007/s00438-012-0701-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 05/29/2012] [Indexed: 01/17/2023]
Abstract
The transition to flowering in winter wheat requires prolonged exposure to low temperature, a process called vernalization. This process is regulated by a genetic pathway that involves at least three genes, Triticum aestivum VERNALIZATION 1 (TaVRN1), Triticum aestivum VERNALIZATION 2 (TaVRN2) and Triticum aestivum FLOWERING LOCUS T-like 1 (TaFT1). These genes regulate flowering by integrating environmental and developmental cues. To determine whether the expression of these genes is associated with the chromatin methylation state during vernalization in wheat, the level of two markers of histone modifications, the activator histone H3 trimethylation of lysine 4 (H3K4me3) and the repressor histone H3 trimethylation of lysine 27 (H3K27me3) were measured at the promoter regions of these three genes. Bioinformatics analysis of these promoters demonstrates the presence of conserved cis-acting elements in the promoters of the three vernalization genes, TaVRN1, TaVRN2 and TaFT1. These elements are targeted by common transcription factors in the vernalization responsive cereals. These promoters also contain the functional "units" PRE/TRE targeted by Polycomb and Trithorax proteins that maintain repressed or active transcription states of developmentally regulated genes. These proteins are known to be associated with the regulation of H3K4me3 and H3K27me3. Expression studies indicate that TaVRN1 and TaFT1 are up-regulated by vernalization in winter wheat. This up-regulation is associated with increased level of the activator H3K4me3 with no change in the level of the repressor H3K27me3 at the promoter region. This study shows that the flowering transition induced by vernalization in winter wheat is associated with histone methylation at the promoter level of TaVRN1 and TaFT1 while the role of these markers is less evident in TaVRN2 repression. This may represent part of the cellular memory of vernalization in wheat.
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Effect of water on the stability of Mo and CoMo hydrodeoxygenation catalysts: A combined experimental and DFT study. J Catal 2011. [DOI: 10.1016/j.jcat.2011.06.006] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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