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Halalsheh M, Shatanawi K, Shawabkeh R, Kassab G, Mohammad H, Adawi M, Ababneh S, Abdullah A, Ghantous N, Balah N, Almomani S. Impact of temperature and residence time on sewage sludge pyrolysis for combined carbon sequestration and energy production. Heliyon 2024; 10:e28030. [PMID: 38596039 PMCID: PMC11002555 DOI: 10.1016/j.heliyon.2024.e28030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 12/15/2023] [Accepted: 03/11/2024] [Indexed: 04/11/2024] Open
Abstract
Environmental challenges related to sewage sludge call for urgent sustainable management of this resource. Sludge pyrolysis might be considered as a sustainable technology and is anticipated to support measures for mitigating climate change through carbon sequestration. The end products of the process have various applications, including the agricultural utilization of biochar, as well as the energy exploitation of bio-oil and syngas. In this research, sewage sludge was pyrolyzed at 500 °C, 600 °C, 750 °C, and 850 °C. At each temperature, pyrolysis was explored at 1hr, 2hrs, and 3hrs residence times. The ratio (H/Corg)at was tapped to imply organic carbon stability and carbon sequestration potential. Optimum operating conditions were achieved at 750 °C and 2hrs residence time. Produced biochar had (H/Corg)at ratio of 0.54, while nutrients' contents based on dry weight were 3.99%, 3.2%, and 0.6% for total nitrogen (TN), total phosphorus (TP), and total potassium (TK), respectively. Electrical conductivity of biochar was lesser than the feed sludge. Heavy metals in biochar aligned with the recommended values of the International Biochar Initiative. Heat content of condensable and non-condensable volatiles was sufficient to maintain the temperature of the furnace provided that PYREG process is considered. However, additional energy source is demanded for sludge drying.
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Affiliation(s)
- M. Halalsheh
- Water, Energy and Environment Center, The University of Jordan, Amman, Jordan
| | - K. Shatanawi
- Civil Engineering Department, School of Engineering, The University of Jordan, Amman, Jordan
| | - R. Shawabkeh
- Department of Chemical Engineering, School of Engineering, The University of Jordan, Amman, Jordan
| | - G. Kassab
- Civil Engineering Department, School of Engineering, The University of Jordan, Amman, Jordan
| | - H. Mohammad
- Water, Energy and Environment Center, The University of Jordan, Amman, Jordan
| | - M. Adawi
- Water, Energy and Environment Center, The University of Jordan, Amman, Jordan
| | - S. Ababneh
- German Development Cooperation, Amman, Jordan
| | - A. Abdullah
- German Development Cooperation, Amman, Jordan
| | - N. Ghantous
- German Development Cooperation, Amman, Jordan
| | - N. Balah
- German Development Cooperation, Amman, Jordan
| | - S. Almomani
- German Development Cooperation, Amman, Jordan
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Mohammad H, Anantram MP. Charge transport through DNA with energy-dependent decoherence. Phys Rev E 2023; 108:044403. [PMID: 37978586 DOI: 10.1103/physreve.108.044403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 09/08/2023] [Indexed: 11/19/2023]
Abstract
Modeling charge transport in DNA is essential to understand and control the electrical properties and develop DNA-based nanoelectronics. DNA is a fluctuating molecule that exists in a solvent environment, which makes the electron susceptible to decoherence. While knowledge of the Hamiltonian responsible for decoherence will provide a microscopic description, the interactions are complex and methods to calculate decoherence are unclear. One prominent phenomenological model to include decoherence is through fictitious probes that depend on spatially variant scattering rates. However, the built-in energy independence of the decoherence (E-indep) model overestimates the transmission in the bandgap and washes out distinct features inside the valence or conduction bands. In this study, we introduce a related model where the decoherence rate is energy-dependent (E-dep). This decoherence rate is maximum at energy levels and decays away from these energies. Our results show that the E-dep model allows for exponential transmission decay with the DNA length and maintains features within the bands' transmission spectra. We further demonstrate that we can obtain DNA conductance values within the experimental range. Our model can help study and design nanoelectronics devices that utilize weakly coupled molecular structures such as DNA.
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Affiliation(s)
- Hashem Mohammad
- Department of Electrical Engineering, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait
| | - M P Anantram
- Department of Electrical and Computer Engineering, University of Washington, Seattle, Washington 98195, USA
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Demir B, Mohammad H, Anantram MP, Oren EE. DNA-Au (111) interactions and transverse charge transport properties for DNA-based electronic devices. Phys Chem Chem Phys 2023. [PMID: 37309195 DOI: 10.1039/d2cp05009a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
DNA's charge transfer and self-assembly characteristics have made it a hallmark of molecular electronics for the past two decades. A fast and efficient charge transfer mechanism with programmable properties using DNA nanostructures is required for DNA-based nanoelectronic applications and devices. The ability to integrate DNA with inorganic substrates becomes critical in this process. Such integrations may affect the conformation of DNA, altering its charge transport properties. Thus, using molecular dynamics simulations and first-principles calculations in conjunction with Green's function approach, we explore the impact of the Au (111) substrate on the conformation of DNA and analyze its effect on the charge transport. Our results indicate that DNA sequence, leading to its molecular conformation on the Au substrate, is critical to engineer charge transport properties. We demonstrate that DNA fluctuates on a gold substrate, sampling various distinct conformations over time. The energy levels, spatial locations of molecular orbitals and the DNA/Au contact atoms can differ between these distinct conformations. Depending on the sequence, at the HOMO, the charge transmission differs up to 60 times between the top ten conformations. We demonstrate that the relative positions of the nucleobases are critical in determining the conformations and the coupling between orbitals. We anticipate that these results can be extended to other inorganic surfaces and pave the way for understanding DNA-inorganic interface interactions for future DNA-based electronic device applications.
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Affiliation(s)
- Busra Demir
- Department of Materials Science & Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara, Turkey.
- Bionanodesign Laboratory, Department of Biomedical Engineering, TOBB University of Economics and Technology, Ankara, Turkey
- Department of Electrical and Computer Engineering, University of Washington, 98195 Seattle, WA, USA
| | - Hashem Mohammad
- Department of Electrical Engineering, Kuwait University, P. O. Box 5969, Safat 13060, Kuwait
| | - M P Anantram
- Department of Electrical and Computer Engineering, University of Washington, 98195 Seattle, WA, USA
| | - Ersin Emre Oren
- Department of Materials Science & Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara, Turkey.
- Bionanodesign Laboratory, Department of Biomedical Engineering, TOBB University of Economics and Technology, Ankara, Turkey
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De A, Mohammad H, Wang Y, Kubendran R, Das AK, Anantram MP. Performance analysis of DNA crossbar arrays for high-density memory storage applications. Sci Rep 2023; 13:6650. [PMID: 37095117 PMCID: PMC10126128 DOI: 10.1038/s41598-023-33004-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 04/05/2023] [Indexed: 04/26/2023] Open
Abstract
Deoxyribonucleic acid (DNA) has emerged as a promising building block for next-generation ultra-high density storage devices. Although DNA has high durability and extremely high density in nature, its potential as the basis of storage devices is currently hindered by limitations such as expensive and complex fabrication processes and time-consuming read-write operations. In this article, we propose the use of a DNA crossbar array architecture for an electrically readable read-only memory (DNA-ROM). While information can be 'written' error-free to a DNA-ROM array using appropriate sequence encodings its read accuracy can be affected by several factors such as array size, interconnect resistance, and Fermi energy deviations from HOMO levels of DNA strands employed in the crossbar. We study the impact of array size and interconnect resistance on the bit error rate of a DNA-ROM array through extensive Monte Carlo simulations. We have also analyzed the performance of our proposed DNA crossbar array for an image storage application, as a function of array size and interconnect resistance. While we expect that future advances in bioengineering and materials science will address some of the fabrication challenges associated with DNA crossbar arrays, we believe that the comprehensive body of results we present in this paper establishes the technical viability of DNA crossbar arrays as low power, high-density storage devices. Finally, our analysis of array performance vis-à-vis interconnect resistance should provide valuable insights into aspects of the fabrication process such as proper choice of interconnects necessary for ensuring high read accuracies.
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Affiliation(s)
- Arpan De
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Hashem Mohammad
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, 98195, USA
- Department of Electrical Engineering, Kuwait University, P.O. Box 5969, 13060, Safat, Kuwait
| | - Yiren Wang
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Rajkumar Kubendran
- Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA, 15261, USA
| | - Arindam K Das
- Department of Computer Science and Electrical Engineering, Eastern Washington University, Cheney, WA, 99004, USA
| | - M P Anantram
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, 98195, USA.
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Wang Y, Demir B, Mohammad H, Oren EE, Anantram MP. Computational study of the role of counterions and solvent dielectric in determining the conductance of B-DNA. Phys Rev E 2023; 107:044404. [PMID: 37198817 DOI: 10.1103/physreve.107.044404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 04/01/2023] [Indexed: 05/19/2023]
Abstract
DNA naturally exists in a solvent environment, comprising water and salt molecules such as sodium, potassium, magnesium, etc. Along with the sequence, the solvent conditions become a vital factor determining DNA structure and thus its conductance. Over the last two decades, researchers have measured DNA conductivity both in hydrated and almost dry (dehydrated) conditions. However, due to experimental limitations (the precise control of the environment), it is very difficult to analyze the conductance results in terms of individual contributions of the environment. Therefore, modeling studies can help us to gain a valuable understanding of various factors playing a role in charge transport phenomena. DNA naturally has negative charges located at the phosphate groups in the backbone, which provides both the connections between the base pairs and the structural support for the double helix. Positively charged ions such as the sodium ion (Na^{+}), one of the most commonly used counterions, balance the negative charges at the backbone. This modeling study investigates the role of counterions both with and without the solvent (water) environment in charge transport through double-stranded DNA. Our computational experiments show that in dry DNA, the presence of counterions affects electron transmission at the lowest unoccupied molecular orbital energies. However, in solution, the counterions have a negligible role in transmission. Using the polarizable continuum model calculations, we demonstrate that the transmission is significantly higher at both the highest occupied and lowest unoccupied molecular orbital energies in a water environment as opposed to in a dry one. Moreover, calculations also show that the energy levels of neighboring bases are more closely aligned to ease electron flow in the solution.
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Affiliation(s)
- Yiren Wang
- Deparment of Electrical and Computer Engineering, University of Washington, Seattle, Washington 98105, USA
| | - Busra Demir
- Bionanodesign Laboratory, Department of Biomedical Engineering, and Department of Materials Science & Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara 06510, Turkey
| | - Hashem Mohammad
- Department of Electrical Engineering, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait
| | - Ersin Emre Oren
- Bionanodesign Laboratory, Department of Biomedical Engineering, and Department of Materials Science & Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara 06510, Turkey
| | - M P Anantram
- Deparment of Electrical and Computer Engineering, University of Washington, Seattle, Washington 98105, USA
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Bareche Y, Kelly D, Abbas-Aghababazadeh F, Nakano M, Esfahani PN, Tkachuk D, Mohammad H, Samstein R, Lee CH, Morris LGT, Bedard PL, Haibe-Kains B, Stagg J. Leveraging big data of immune checkpoint blockade response identifies novel potential targets. Ann Oncol 2022; 33:1304-1317. [PMID: 36055464 DOI: 10.1016/j.annonc.2022.08.084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 08/03/2022] [Accepted: 08/22/2022] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND The development of immune checkpoint blockade (ICB) has changed the way we treat various cancers. While ICB produces durable survival benefits in a number of malignancies, a large proportion of treated patients do not derive clinical benefit. Recent clinical profiling studies have shed light on molecular features and mechanisms that modulate response to ICB. Nevertheless, none of these identified molecular features were investigated in large enough cohorts to be of clinical value. MATERIALS AND METHODS Literature review was carried out to identify relevant studies including clinical dataset of patients treated with ICB [anti-programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1), anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) or the combination] and available sequencing data. Tumor mutational burden (TMB) and 37 previously reported gene expression (GE) signatures were computed with respect to the original publication. Biomarker association with ICB response (IR) and survival (progression-free survival/overall survival) was investigated separately within each study and combined together for meta-analysis. RESULTS We carried out a comparative meta-analysis of genomic and transcriptomic biomarkers of IRs in over 3600 patients across 12 tumor types and implemented an open-source web application (predictIO.ca) for exploration. TMB and 21/37 gene signatures were predictive of IRs across tumor types. We next developed a de novo GE signature (PredictIO) from our pan-cancer analysis and demonstrated its superior predictive value over other biomarkers. To identify novel targets, we computed the T-cell dysfunction score for each gene within PredictIO and their ability to predict dual PD-1/CTLA-4 blockade in mice. Two genes, F2RL1 (encoding protease-activated receptor-2) and RBFOX2 (encoding RNA-binding motif protein 9), were concurrently associated with worse ICB clinical outcomes, T-cell dysfunction in ICB-naive patients and resistance to dual PD-1/CTLA-4 blockade in preclinical models. CONCLUSION Our study highlights the potential of large-scale meta-analyses in identifying novel biomarkers and potential therapeutic targets for cancer immunotherapy.
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Affiliation(s)
- Y Bareche
- Faculty of Pharmacy, Université de Montréal, Montreal, Canada; Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Institut du Cancer de Montréal, Montreal, Canada
| | - D Kelly
- Princess Margaret Cancer Centre, University Health Network, Division of Medical Oncology and Hematology, Toronto, Canada
| | - F Abbas-Aghababazadeh
- Princess Margaret Bioinformatics and Computational Genomics Laboratory, University Health Network, Toronto, Canada
| | - M Nakano
- Princess Margaret Bioinformatics and Computational Genomics Laboratory, University Health Network, Toronto, Canada
| | - P N Esfahani
- Princess Margaret Bioinformatics and Computational Genomics Laboratory, University Health Network, Toronto, Canada
| | - D Tkachuk
- Princess Margaret Bioinformatics and Computational Genomics Laboratory, University Health Network, Toronto, Canada
| | - H Mohammad
- Princess Margaret Bioinformatics and Computational Genomics Laboratory, University Health Network, Toronto, Canada
| | - R Samstein
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, USA
| | - C-H Lee
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, USA
| | - L G T Morris
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, USA
| | - P L Bedard
- Princess Margaret Cancer Centre, University Health Network, Division of Medical Oncology and Hematology, Toronto, Canada
| | - B Haibe-Kains
- Princess Margaret Bioinformatics and Computational Genomics Laboratory, University Health Network, Toronto, Canada; Princess Margaret Cancer Centre, University Health Network, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada; Department ofComputer Science, University of Toronto, Toronto, Canada; Department ofOntario Institute for Cancer Research, Toronto, Canada; Department ofVector Institute for Artificial Intelligence, Toronto, Canada; Department ofBiostatistics Division, Dalla Lana School of Public Health, Toronto, Canada.
| | - J Stagg
- Faculty of Pharmacy, Université de Montréal, Montreal, Canada; Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Institut du Cancer de Montréal, Montreal, Canada.
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Khalifa E, El-Sateh A, Zeeneldin M, Abdelghany AM, Hosni M, Abdallah A, Salama S, Abdel-Rasheed M, Mohammad H. Effect of maternal BMI on labor outcomes in primigravida pregnant women. BMC Pregnancy Childbirth 2021; 21:753. [PMID: 34749684 PMCID: PMC8574020 DOI: 10.1186/s12884-021-04236-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 10/20/2021] [Indexed: 11/23/2022] Open
Abstract
Background This study aims to detect the effects of increased BMI on labor outcomes in primigravida pregnant women. Methods A cross-sectional study involved 600 full-term singleton primigravida pregnant women who presented in the active phase of labor to the labor ward. They were divided according to BMI into three equals groups; women with normal BMI (group I), overweight women (group II), and women with class I obesity (group III). Results We found that high BMI was associated with a significantly increased risk of Caesarean section (C.S.) (13% in group I, 18% in group II and 40% in group III). Women with higher BMI and delivered vaginally had a significantly prolonged first and second stage of labor, consequently increased the need for oxytocin augmentation as well as the oxytocin dose. Regarding the maternal and fetal outcomes, there are significantly increased risks of postpartum sepsis, perineal tears, wound infection, as well as significantly increased birth weight and longer neonatal stay in the neonatal unit (NNU). Conclusion Obese primigravida pregnant women were at higher risk of suboptimal outcomes. Besides, prolonged first and second stages of labor and the incidence of C.S. have also been increased.
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Affiliation(s)
- Eissa Khalifa
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minya, Egypt
| | - Alaa El-Sateh
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minya, Egypt
| | - Mohamed Zeeneldin
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minya, Egypt
| | - Ahmed M Abdelghany
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minya, Egypt
| | - Mahmoud Hosni
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minya, Egypt
| | - Ameer Abdallah
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minya, Egypt
| | - Sameh Salama
- Reproductive Health Research Department, National Research Centre, 33 El-Buhouth St, Dokki, Cairo, 12622, Egypt
| | - Mazen Abdel-Rasheed
- Reproductive Health Research Department, National Research Centre, 33 El-Buhouth St, Dokki, Cairo, 12622, Egypt.
| | - Hashem Mohammad
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minya, Egypt
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Mohammad H, Madsen K, Graumann O, Loya AC, Jensen NV, Dahlrot RH. Metastatic atypical renal tumour with metanephric characteristics treated with Sunitinib. Urol Case Rep 2021; 40:101880. [PMID: 34692420 PMCID: PMC8517833 DOI: 10.1016/j.eucr.2021.101880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 09/29/2021] [Accepted: 10/05/2021] [Indexed: 11/30/2022] Open
Abstract
Metanephric Adenoma (MA) is a rare and unclassifiable renal tumour with sparse reported clinical and morphological features. Generally MA's have a benign course without recurrence after nephrectomy, however a few cases received oncological treatment due to malignant progression. We present a 42-year-old woman who years after an initial nephrectomy developed several processes and biopsy confirmed recurrence of MA. Sunitinib was given for only two weeks, as she developed side-effects and currently the patient undergoes control scans with only minimal growth of the processes. This is the first case of MA treated with Tyrosin-Kinase-Inhibitor.
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Affiliation(s)
- H Mohammad
- Department of Oncology, Odense University Hospital, Odense, Denmark
| | - K Madsen
- Department of Pathology, Odense University Hospital, Odense, Denmark.,Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense, Denmark
| | - O Graumann
- Department of Radiology, Odense University Hospital, Odense, Denmark.,Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - A C Loya
- Department of Pathology, Rigshospitalet, Copenhagen, Denmark.,Institute for Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - N V Jensen
- Department of Oncology, Odense University Hospital, Odense, Denmark
| | - R H Dahlrot
- Department of Oncology, Odense University Hospital, Odense, Denmark.,Department of Clinical Research, University of Southern Denmark, Odense, Denmark
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Mohammad H, Demir B, Akin C, Luan B, Hihath J, Oren EE, Anantram MP. Role of intercalation in the electrical properties of nucleic acids for use in molecular electronics. Nanoscale Horiz 2021; 6:651-660. [PMID: 34190284 DOI: 10.1039/d1nh00211b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Intercalating ds-DNA/RNA with small molecules can play an essential role in controlling the electron transmission probability for molecular electronics applications such as biosensors, single-molecule transistors, and data storage. However, its applications are limited due to a lack of understanding of the nature of intercalation and electron transport mechanisms. We addressed this long-standing problem by studying the effect of intercalation on both the molecular structure and charge transport along the nucleic acids using molecular dynamics simulations and first-principles calculations coupled with the Green's function method, respectively. The study on anthraquinone and anthraquinone-neomycin conjugate intercalation into short nucleic acids reveals some universal features: (1) the intercalation affects the transmission by two mechanisms: (a) inducing energy levels within the bandgap and (b) shifting the location of the Fermi energy with respect to the molecular orbitals of the nucleic acid, (2) the effect of intercalation was found to be dependent on the redox state of the intercalator: while oxidized anthraquinone decreases, reduced anthraquinone increases the conductance, and (3) the sequence of the intercalated nucleic acid further affects the transmission: lowering the AT-region length was found to enhance the electronic coupling of the intercalator with GC bases, hence yielding an increase of more than four times in conductance. We anticipate our study to inspire designing intercalator-nucleic acid complexes for potential use in molecular electronics via creating a multi-level gating effect.
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Affiliation(s)
- Hashem Mohammad
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA.
| | - Busra Demir
- Bionanodesign Laboratory, Department of Biomedical Engineering, TOBB University of Economics and Technology, Ankara, Turkey. and Department of Materials Science & Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara, Turkey
| | - Caglanaz Akin
- Bionanodesign Laboratory, Department of Biomedical Engineering, TOBB University of Economics and Technology, Ankara, Turkey. and Department of Materials Science & Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara, Turkey
| | - Binquan Luan
- Computational Biological Center, IBM Thomas J. Watson Research, Yorktown Heights, NY 10598, USA
| | - Joshua Hihath
- Electrical and Computer Engineering Department, University of California Davis, Davis, CA, USA
| | - Ersin Emre Oren
- Bionanodesign Laboratory, Department of Biomedical Engineering, TOBB University of Economics and Technology, Ankara, Turkey. and Department of Materials Science & Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara, Turkey
| | - M P Anantram
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA.
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Khalifa E, Mohammad H, Abdullah A, Abdel-Rasheed M, Khairy M, Hosni M. Role of suppression of endometriosis with progestins before IVF-ET: a non-inferiority randomized controlled trial. BMC Pregnancy Childbirth 2021; 21:264. [PMID: 33784989 PMCID: PMC8011082 DOI: 10.1186/s12884-021-03736-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 03/18/2021] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Endometriosis affects the responsiveness to ovarian stimulation. This study aimed to assess the role of Dienogest pretreatment for endometriosis suppression as compared to Gonadotropin-releasing hormone agonist (GnRHa) in patients with endometriosis pursuing IVF treatment. METHODS In this randomized controlled trial, 134 women with endometriosis-related infertility were randomly allocated to group A (n = 67) who had monthly depot GnRHa for 3 months before ovarian stimulation in IVF treatment (Ultra-long protocol), and Group B (n = 67) who had daily oral Dienogest 2 mg/d for 3 months before starting standard long protocol for IVF. The primary outcome measure was the number of oocytes retrieved. The secondary outcome measures included the number of mature oocytes, fertilization rate, quality of life assessed by FertiQoL scores, cost of treatment, and pregnancy outcomes. RESULTS Although there was no statistically significant difference between both groups regarding ovarian stimulation, response parameters, and pregnancy outcomes, the Dienogest group had a lower cost of treatment (2773 vs. 3664 EGP, P < 0.001), lower side effects (29.9% vs. 59.7%, P < 0.001), higher FertiQoL treatment scores (33.2 vs. 25.1, P < 0.001) and higher tolerability scores (14.1 vs. 9.4, P < 0.001 < 0.001). CONCLUSION Our study indicates that Dienogest is a suitable and safe substitute for GnRHa pretreatment in endometriosis patients. TRIAL REGISTRATION NCT04500743 "Retrospectively registered on August 5, 2020".
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Affiliation(s)
- Eissa Khalifa
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minia, Egypt
| | - Hashem Mohammad
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minia, Egypt
| | - Ameer Abdullah
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minia, Egypt
| | - Mazen Abdel-Rasheed
- Reproductive Health Research Department, National Research Centre, 33 El-Buhouth St, Dokki, Cairo, 12622, Egypt.
| | - Mohammed Khairy
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minia, Egypt
| | - Mahmoud Hosni
- Obstetrics and Gynecology Department, Faculty of Medicine, Minia University, Minia, Egypt
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Menon-Johansson AS, Curtis H, Mohammad H, Hamlyn E, Hughes A, McClean H, Pal N, Tayal S, Sullivan AK. Improved results demonstrated in the 2017 national audit of early syphilis management in the United Kingdom. Int J STD AIDS 2020; 31:375-379. [PMID: 32041481 DOI: 10.1177/0956462419896706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The revised British Association of Sexual Health and HIV UK guidelines on the management of syphilis were published in 2015 and this audit measures performance against those standards and recommendations. Although not included in the guideline recommendations, an exploratory question on clinics’ HIV testing policy was also included. The audit was conducted over a two-month period in 2017 in genitourinary medicine (GUM) clinics across the UK of cases presenting in 2016. A total of 161 GUM clinics participated, and data were collected for 3017 cases. The standard for adherence to recommended treatment was met (97%, standard: 97%) and almost met for documented pre-treatment syphilis serology (95%, standard: 97%). Even though only 74% of patients had a documented action in relation to informing sexual contacts (standard: 97%), the standard for contacts seen and tested per index case within four weeks was met (0.9, standard: 0.6). Finally, those clinics with a formal policy on HIV testing after a syphilis diagnosis were twice as likely to test after the HIV window period, compared to clinics without a policy; a concurrent HIV diagnosis was made in 75 (3%) patients. More work is required to standardize documented delivery of effective partner notification and a formal policy on HIV testing appears to be effective.
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Affiliation(s)
| | - H Curtis
- British HIV Association, London, UK
| | | | - E Hamlyn
- Chelsea and Westminster NHS Foundation Trust, London, UK
| | | | - H McClean
- Royal Society of Medicine, Cheshire, UK
| | - N Pal
- Berkshire Healthcare Foundation Trust, Garden Clinic, Upton Hospital, Slough, UK
| | | | - A K Sullivan
- Chelsea and Westminster NHS Foundation Trust, London, UK
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12
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Abas NH, Abd Rahman R, Mohammad H, Rahmat MH. Designer’s Confidence and Attitude towards Designing-for-Construction-Safety (DfCS) Implementation. IOP Conf Ser : Mater Sci Eng 2020; 713:012045. [DOI: 10.1088/1757-899x/713/1/012045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Abstract
The construction industry is known as a hazardous industry, which has been overwhelmed with accidents for a long time. One of the new strategies to reduce the number of accident in Malaysia is through emphasizing the safety responsibility on the parties involved during the design stage. This study investigated the confidence level of designing-for- construction-safety (DfCS) and the perceptions of the hindrance by focusing on the role of designers and its implementation among construction designers. The quantitative approach had been used, in which questionnaire survey forms were distributed via email and self-administered to forty (40) construction designers (i.e. civil and construction engineer, quantity surveyor, architect) in Johor. The findings have revealed that the respondents are confident of their ability to design for construction safety, though they are relatively less willing to implement the concept. This study demonstrates that significant effort is required to promote the benefits of DfCS in improving the safety performance of the construction industry so that it is widely accepted and implemented by the construction stakeholders.
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Mohammad H, Marchisella F, Ortega-Martinez S, Hollos P, Eerola K, Komulainen E, Kulesskaya N, Freemantle E, Fagerholm V, Savontous E, Rauvala H, Peterson BD, van Praag H, Coffey ET. JNK1 controls adult hippocampal neurogenesis and imposes cell-autonomous control of anxiety behaviour from the neurogenic niche. Mol Psychiatry 2018; 23:487. [PMID: 28194007 PMCID: PMC5794892 DOI: 10.1038/mp.2017.21] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
This corrects the article DOI: 10.1038/mp.2016.203.
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14
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Mohammad H, Evans J. A study of the accuracy of deep brain stimulation electrode placement in patients undergoing movement disorder surgery. Int J Surg 2016. [DOI: 10.1016/j.ijsu.2016.08.303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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15
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Mohammad H, Rahman MM, Hossain MA, Amin M, Somon AU. A 47 Years Lady with Intrathoracic Lipoma. Mymensingh Med J 2016; 25:357-358. [PMID: 27277371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A case of a 47 years old female who presented to Mymensingh Medical College Hospital, Medicine Unit-5, complaining of severe dyspnea and occasional leg swelling. Chest X-ray, USG of chest and chest CT scan revealed a right sided giant intrathoracic mass extending across the posterior mediastinum into the left chest cavity. CT guided FNAC of right lung revealed lipoma.
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Affiliation(s)
- H Mohammad
- Dr Hanif Mohammad, Associate Professor, Department of Medicine, Mymensingh Medical College, Mymensingh, Bangladesh; E-mail:
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16
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Ampeng A, Shukor MN, Sahibin AR, Idris WMR, Ahmad S, Mohammad H, Madeline GP, Ali N, Bujang M, Hashim I, Bujang A, Md-Zain BM. Patterns of mineral lick use by Northwest Bornean orangutans (Pongo pygmaeus pygmaeus) in the Lanjak Entimau Wildlife Sanctuary, Sarawak, Malaysia. EUR J WILDLIFE RES 2016. [DOI: 10.1007/s10344-015-0983-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Mohammad H, Belgrave D, Harding K, Simpson A, Custovic A. P46 The Influence Of Age And Gender On Allergy Test Results: Implications For The Use As Biomarkers In Childhood Asthma. Thorax 2014. [DOI: 10.1136/thoraxjnl-2014-206260.187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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18
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Mohammad H, Smitheman K, van Aller G, Cusan M, Kamat S, Liu Y, Johnson N, Hann C, Armstrong S, Kruger R. 212 Novel anti-tumor activity of targeted LSD1 inhibition by GSK2879552. Eur J Cancer 2014. [DOI: 10.1016/s0959-8049(14)70338-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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19
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Hussain T, Mohammad H. The effect of transcutaneous electrical nerve stimulation (TENS) combined with Bobath on post stroke spasticity. A randomized controlled study. J Neurol Sci 2013. [DOI: 10.1016/j.jns.2013.07.1964] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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20
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Dey PK, Sutradhar SR, Barman TK, Khan NA, Hasan I, Haque MF, Sumon SM, Islam MZ, Mohammad H, Huda MN. Risk factors of non-alcoholic fatty liver disease. Mymensingh Med J 2013; 22:649-654. [PMID: 24292291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
This case control study was carried out in Mymensingh Medical College Hospital, Mymensingh, Bangladesh and Dhaka Medical College Hospital, Dhaka, Bangladesh from November 2010 to October 2011 to find out the risk factors of non-alcoholic fatty liver disease. A total of 90 participants (45 cases and 45 controls) were included. A higher proportion of patients with age >45 years were found in case group compared to control (51.1% vs. 15.6%). The mean age was significantly higher in case group 49.8±12.6 years. Males demonstrated their predominance in both case (62.2%) and control (68.9%) groups, although the two groups did not differ in terms of sex distribution. Body mass index demonstrates that 26.7% of patients in case group were of normal weight, 46.7% overweight and 26.7% obese. In the control group, two-thirds (68.9%) of the patients were of normal weight and 24.4% overweight and 7.8% obese. Diabetes and hypertension were significantly present in the case group than those in control counterparts 75.6% vs. 15.6% and 86.7% vs. 15.6 % respectively. The mean fasting blood glucose, ALT, total cholesterol and triglycerides were significantly higher in case group compared to control group 7.8±1.3 vs. 5.4±2.5mmol/L (p<0.001); 39.1±12.4 vs. 30.3±14.1IU/L, (p=0.002); 239.9±14.3 vs. 183.3±11.4mg/dl, (p<0.001) and 183.6±12.5 vs. 133.5±16.0mg/dl, (p<0.001) respectively. However, no significant difference was observed between the case and the control groups in terms of HDL cholesterol (35.9±1.2 vs. 38.0±1.1mg/dl, p=0.203). Majority of the patients in case group (88.9%) exhibited increased echogenicity of liver on ultrasonogram as opposed to 15.6% in the control group.
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Affiliation(s)
- P K Dey
- Dr Pulak Kumar Dey, Indoor Medical Officer, Department of Medicine, Mymensingh Medical College Hospital (MMCH), Mymensingh, Bangladesh
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Cai Y, Geutjes EJ, de Lint K, Roepman P, Bruurs L, Yu LR, Wang W, van Blijswijk J, Mohammad H, de Rink I, Bernards R, Baylin SB. The NuRD complex cooperates with DNMTs to maintain silencing of key colorectal tumor suppressor genes. Oncogene 2013; 33:2157-68. [PMID: 23708667 DOI: 10.1038/onc.2013.178] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 03/25/2013] [Accepted: 03/28/2013] [Indexed: 11/09/2022]
Abstract
Many tumor suppressor genes (TSGs) are silenced through synergistic layers of epigenetic regulation including abnormal DNA hypermethylation of promoter CpG islands, repressive chromatin modifications and enhanced nucleosome deposition over transcription start sites. The protein complexes responsible for silencing of many of such TSGs remain to be identified. Our previous work demonstrated that multiple silenced TSGs in colorectal cancer cells can be partially reactivated by DNA demethylation in cells disrupted for the DNA methyltransferases 1 and 3B (DNMT1 and 3B) or by DNMT inhibitors (DNMTi). Herein, we used proteomic and functional genetic approaches to identify additional proteins that cooperate with DNMTs in silencing these key silenced TSGs in colon cancer cells. We discovered that DNMTs and the core components of the NuRD (Mi-2/nucleosome remodeling and deacetylase) nucleosome remodeling complex, chromo domain helicase DNA-binding protein 4 (CHD4) and histone deacetylase 1 (HDAC1) occupy the promoters of several of these hypermethylated TSGs and physically and functionally interact to maintain their silencing. Consistent with this, we find an inverse relationship between expression of HDAC1 and 2 and these TSGs in a large panel of primary colorectal tumors. We demonstrate that DNMTs and NuRD cooperate to maintain the silencing of several negative regulators of the WNT and other signaling pathways. We find that depletion of CHD4 is synergistic with DNMT inhibition in reducing the viability of colon cancer cells in correlation with reactivation of TSGs, suggesting that their combined inhibition may be beneficial for the treatment of colon cancer. Since CHD4 has ATPase activity, our data identify CHD4 as a potentially novel drug target in cancer.
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Affiliation(s)
- Y Cai
- Department of Oncology and The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, Baltimore, MD, USA
| | - E-J Geutjes
- Division of Molecular Carcinogenesis, Center for Biomedical Genetics and Cancer Genomics Centre, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - K de Lint
- Division of Molecular Carcinogenesis, Center for Biomedical Genetics and Cancer Genomics Centre, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - P Roepman
- Department of Research and Development, Agendia NV, Amsterdam, The Netherlands
| | - L Bruurs
- Division of Molecular Carcinogenesis, Center for Biomedical Genetics and Cancer Genomics Centre, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - L-R Yu
- Division of Systems Biology, Center of Excellence for Proteomics, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR, USA
| | - W Wang
- Department of Oncology and The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, Baltimore, MD, USA
| | - J van Blijswijk
- Division of Molecular Carcinogenesis, Center for Biomedical Genetics and Cancer Genomics Centre, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - H Mohammad
- Department of Oncology and The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, Baltimore, MD, USA
| | - I de Rink
- Central Microarray and Deep Sequencing Core Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - R Bernards
- Division of Molecular Carcinogenesis, Center for Biomedical Genetics and Cancer Genomics Centre, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - S B Baylin
- Department of Oncology and The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, Baltimore, MD, USA
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Sarkar DN, Amin R, Mohammad H, Azhar MA, Faiz MA. Treatment outcome of national guideline based antitubercular chemotherapy in tubercular ascites patients. Mymensingh Med J 2013; 22:358-364. [PMID: 23715362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Adenosine De Aminase (ADA) is increased in tuberculous ascitic fluid due to the stimulation of T-cells by mycobacterial antigens. The treatment for abdominal tuberculosis including ascites as a presentation is a matter of controversy around the world. The study is aim at to see the outcome of antitubercular chemotherapy in selected tubercular ascites patients. This hospital based prospective study was done in 24 cases of adult (>13 years) tubercular ascites admitted in a tertiary hospital Dhaka, over one year. Increased ADA level (>37iu/L) in ascitic fluid evaluated after the colorimetric method of Galanti and Giusti and other supportive investigations were done for diagnosing tuberculosis. Patients were under treatment of ATT cat-1 for six months as per national guide line. Outcome was seen as predefined criteria as treatment completed, cured, improved and not improved. Total number of patient is 24. Of which range of age is 13-70 years and mean±SD (33.2±14.77) with male female ratio is 0.85:1. Ninety six percent patients presented with abdominal pain, 23(96%) with fever, 22 (91%) with anorexia. Abdominal tenderness in 22(91%), ascites on 24(100%), hepatomegaly on 2(8%). Hundred percent patients were evaluated after completion of treatment. Twenty three (96%) patients improved and 1(4%) not improved. There is effectiveness of standard chemotherapy suggested by national guideline. Outcome of the patients were highly satisfactory with short regimen of antitubercular chemotherapy.
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Affiliation(s)
- D N Sarkar
- Rangpur Medical College, Rangpur, Bangladesh
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Mue D, Yongu W, Mohammad H, Kortor J, Elachi I, Donwa J. Intra-operative implantation errors during hemiarthroplasty. J West Afr Coll Surg 2012; 2:79-94. [PMID: 25453005 PMCID: PMC4220481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
BACKGROUND Hemiarthroplasty with Austin Moore endoprosthesis is an established treatment modality for displaced intracapsular femoral neck fractures in elderly patients above 60years.Technical errors in implantation of the un-cemented Austin Moore are common, and have been associated with complications that may culminate in early prosthetic failure requiring revision surgery. OBJECTIVE To analyse the frequency of technical errors experienced by surgeons during implantation of uncemented Austin Moore endoprosthesis with the view to improving technique and minimizing early prosthetic failure. MATERIALS AND METHODS This is a 5year retrospective analysis of radiographs of patients who had hemiarthroplasty with un-cemented Austin Moore endoprosthesis conducted at NKST rehabilitation hospital Mkar in Benue State, North- Central Nigeria with particular reference to intraoperative errors associated with early failure of the prosthesis. Data was analysed using SPSS version 21. RESULTS A total of 48 patients were operated by 3 orthopaedic surgeons and 35patients met the required criteria for the study.Twenty five intraoperative errors in implantation were identified in 16(45.7%) patients. The commonest intraoperative error was inadequate length of the neck remnant in 13(37.1%) patients followed by inadequate calcar seating in 3 (8.6%) patients, incorrect prosthetic head size in 2(5.7%) patients, intraoperative periprosthetic fracture 2(5.7%) patients and inadequate proximal metaphyseal fill in 1(2.9%) patient. CONCLUSION Hemiarthroplasty is a technically demanding procedure frequently associated with intraoperative implantation errors. Adequate pre-operative planning, Careful patient selection, proper training of surgeons as well as attention to detail is vital and may minimize technical errors during implantation and consequent early prosthetic failure.
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Abstract
BACKGROUND The uremic state is characterized by subnormal platelet aggregation. Fibrinogen fragments, usually absent in normal human blood, but present in uremic plasma, may play a role in uremic platelet dysfunction. METHODS To examine this hypothesis, we investigated the availability and function of fibrinogen receptors [glycoprotein (GP) IIb-IIIa] on uremic and normal platelets, as well as the effect of fragments obtained from chymotrypsin digestion of human fibrinogen on normal platelets. The availability of fibrinogen receptors was examined using anti-GP IIb-IIIa antibodies and flow cytometry, whereas receptor function was assessed by the receptor's ability to mediate fibrinogen binding and platelet aggregation. RESULTS Platelet aggregation and the availability of GP IIb-IIIa were lower in uremic patients when compared with normal controls. Flow cytometric analysis showed that fibrinogen fragments decreased the binding of anti-CD61, an activation-independent anti-GP IIIa monoclonal antibody, to resting normal platelets. These fragments also reduced the binding of PAC-1, an activation-dependent anti-GP IIb-IIIa monoclonal antibody, to adenosine diphosphate (ADP)-activated normal platelets. In addition, the binding of radiolabeled fibrinogen to activated normal platelets and platelet aggregation in response to ADP were both decreased by fibrinogen fragments. CONCLUSIONS These findings suggest that fibrinogen fragments impair platelet function by occupying fibrinogen receptors prior to cell activation, thus preventing the binding of intact fibrinogen to platelets after subsequent stimulation. These observations also suggest a plausible mechanism by which endogenous fibrinogen fragments present in uremic plasma may contribute to platelet dysfunction.
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