197 research outputs found

    Aboodh Transform Homotopy Perturbation Method For Solving System Of Nonlinear Partial Differential Equations

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    In this paper, we apply a new method called Aboodh transform homotopy perturbation method (ATHPM) to solve nonlinear systems of partial differential equations. This method is a combination of the new integral transform “Aboodh transform” and the homotopy perturbation method. This method was found to be more effective and easy to solve linear and nonlinear differential equations. Key word:Aboodh  transform Homotopy  perturbation  method Nonlinear  systems  of  partial differential equation

    Nanosized rods agglomerates as a new approach for formulation of a dry powder inhaler

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    HF Salem1 ME Abdelrahim2 K Abo Eid3 MA Sharaf3,41Department of Pharmaceutics, 2Department of Clinical Pharmacy, Faculty of Pharmacy, The University of Beni Suef, Beni Suef; 3Department of Chemistry, Helwan University, Ain Helwan, Helwan, Egypt; 4Department of Chemistry, The American University in Cairo, New Cairo, Helwan 11835, EgyptBackground: Nanosized dry powder inhalers provide higher stability for poorly water-soluble drugs as compared with liquid formulations. However, the respirable particles must have a diameter of 1–5 µm in order to deposit in the lungs. Controlled agglomeration of the nanoparticles increases their geometric particle size so they can deposit easily in the lungs. In the lungs, they fall apart to reform nanoparticles, thus enhancing the dissolution rate of the drugs. Theophylline is a bronchodilator with poor solubility in water.Methods: Nanosized theophylline colloids were formed using an amphiphilic surfactant and destabilized using dilute sodium chloride solutions to form the agglomerates.Results: The theophylline nanoparticles thus obtained had an average particle size of 290 nm and a zeta potential of −39.5 mV, whereas the agglomerates were 2.47 µm in size with a zeta potential of −28.9 mV. The release profile was found to follow first-order kinetics (r2 > 0.96). The aerodynamic characteristics of the agglomerated nanoparticles were determined using a cascade impactor. The behavior of the agglomerate was significantly better than unprocessed raw theophylline powder. In addition, the nanoparticles and agglomerates resulted in a significant improvement in the dissolution of theophylline.Conclusion: The results obtained lend support to the hypothesis that controlled agglomeration strategies provide an efficient approach for the delivery of poorly water-soluble drugs into the lungs.Keywords: theophylline, nanoparticles, agglomerates, dry powder inhale

    Investigation of in-plane moment connections of I-beams to square concrete-filled steel tube columns under gravity loads

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    AbstractThis paper focuses on experimental and analytical behavior of the ultimate moment of the connections of steel I-beams to square concrete-filled steel tube columns. External stiffeners around the columns are used at the beam flange levels. Five specimens are tested monotonically. The test parameters are the column stiffener dimensions and filling the steel tube column with concrete. Two types of failure modes are observed; beam flange failure and stiffener failure. The experimental results show that the ultimate moment of the connection is increased by increasing stiffener’s dimensions and filling the steel tube column with concrete. ANSYS finite element program is used to simulate the behavior, taking into account both geometric and material nonlinearities. Analytical results that are in fair agreement with the experimental ones are then used to discuss the influence of the main geometric parameters on the connection behavior. The parameters are the stiffener and column dimensions as well as filling the steel tube column with concrete. Different square column cross sections are chosen to cover the three classes of section classifications according to Egyptian code of practice, which are: compact, non compact or slender. The increase in the ultimate moment of the connections is based upon both column cross sections’ compactness and stiffener dimensions while the maximum advantages occur with slender columns

    ARA-Homotopy Perturbation Technique with Applications

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    In this study, we propose a novel combination method between the ARA integral transform and the homotopy perturbation approach to solve systems of nonlinear partial differential equations. The difficulty arising in solving nonlinear partial differential equations could simply be overcome by using He’s polynomials during the application of the new method. The proposed technique can provide the solutions of the target problems without pre-assumptions or restrictive constrains in addition to avoiding the round-off errors. The efficiency of the new method is illustrated by applying it to solve different examples of systems of nonlinear partial differential equations. We discuss three interesting applications and solve them by the new approach, called ARA-homotopy perturbation method and get exact solutions, also the results are illustrated in figures

    Adverse pregnancy outcomes in sickle cell trait: a prospective cohort study evaluating clinical and haematological parameters in postpartum mothers and newborns

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    Background: Sickle cell trait (SCT) is a congenital condition caused by the inheritance of a single allele of the abnormal haemoglobin beta gene, HbS. Carriers of SCT are generally asymptomatic, and they do not manifest the clinical and haematological abnormalities of sickle cell anaemia (SCA). However, there is evidence that they display some symptoms in stressful situations. Pregnancy is a stressful physiological event, and it is not clear if SCT adversely affects pregnancy outcomes, particularly in those from developing countries where people regularly suffer from nutritional insufficiency. Objective: This study aims to investigate pregnancy outcomes in Sudanese women with SCT. Subjects and methods: Pregnant women with (HbAS, n=34) and without (HbAA, n=60) SCT were recruited during their first trimester at El Obeid Hospital, Kordofan, Western Sudan. Following appropriate ethical approval and informed consent from the participants, detailed anthropometric, clinical, haematological, obstetric, and birth outcome data were registered. In addition, blood samples were collected at enrolment and at delivery. Results: At enrolment in the first trimester, the SCT group did not manifest SCA symptoms, and there was no difference in the haematological parameters between the SCT and control groups. However, at delivery, the women with SCT, compared with the control group, had lower levels of hemoglobin (Hb, p=0.000), packed cell volume (PCV, p=0.000), mean corpuscular haemoglobin (MCH, p=0.002) and neutrophil counts (p=0.045) and higher mean corpuscular volume (MCV, p=0.000) and platelet counts (p=0.000). Similarly, at delivery, the babies of SCT women had lower birth weight (p=0.000), lower Hb (p=0.045), PCV (p=0.000), MCH (p=0.000), and higher neutrophil (p=0.004) and platelet counts (p=0.000) than the babies of the healthy control group. Additionally, there were more miscarriages, stillbirths, and admissions to the Special Care Baby Unit (SCBU) in the SCT group. Conclusions: The study revealed that SCT is associated with adverse pregnancy outcomes, including maternal and neonatal anaemia, low birth weight, and increased risk of stillbirth, miscarriage, and admission to SCBU. Therefore, pregnant women with SCT should be given appropriate pre-conceptual advice and multidisciplinary antenatal and postnatal care

    The role of non-invasive ventilation in weaning and decannulating critically ill patients with tracheostomy: A narrative review of the literature

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    Abstract Introduction Invasive mechanical ventilation (IMV) is associated with several complications. Placement of a long-term airway (tracheostomy) is also associated with short and long-term risks for patients. Nevertheless, tracheostomies are placed to help reduce the duration of IMV, facilitate weaning and eventually undergo successful decannulation. Methods We performed a narrative review by searching PubMed, Embase and Medline databases to identify relevant citations using the search terms (with synonyms and closely related words) "non-invasive ventilation", "tracheostomy" and "weaning". We identified 13 publications comprising retrospective or prospective studies in which non-invasive ventilation (NIV) was one of the strategies used during weaning from IMV and/or tracheostomy decannulation. Results In some studies, patients with tracheostomies represented a subgroup of patients on IMV. Most of the studies involved patients with underlying cardiopulmonary comorbidities and conditions, and primarily involved specialized weaning centres. Not all studies provided data on decannulation, although those which did, report high success rates for weaning and decannulation when using NIV as an adjunct to weaning patient off ventilatory support. However, a significant percentage of patients still needed home NIV after discharge. Conclusions The review supports a potential role for NIV in weaning patients with a tracheostomy either off the ventilator and/or with its decannulation. Additional research is needed to develop weaning protocols and better characterize the role of NIV during weaning

    Tolfenamic Acid Induces Apoptosis and Growth Inhibition in Head and Neck Cancer: Involvement of NAG-1 Expression

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    Nonsteroidal anti-inflammatory drug-activated gene-1 (NAG-1) is induced by nonsteroidal anti-inflammatory drugs and possesses proapoptotic and antitumorigenic activities. Although tolfenamic acid (TA) induces apoptosis in head and neck cancer cells, the relationship between NAG-1 and TA has not been determined. This study investigated the induction of apoptosis in head and neck cancer cells treated by TA and the role of NAG-1 expression in this induction. TA reduced head and neck cancer cell viability in a dose-dependent manner and induced apoptosis. The induced apoptosis was coincident with the expression of NAG-1. Overexpression of NAG-1 enhanced the apoptotic effect of TA, whereas suppression of NAG-1 expression by small interfering RNA attenuated TA-induced apoptosis. TA significantly inhibited tumor formation as assessed by xenograft models, and this result accompanied the induction of apoptotic cells and NAG-1 expression in tumor tissue samples. Taken together, these results demonstrate that TA induces apoptosis via NAG-1 expression in head and neck squamous cell carcinoma, providing an additional mechanistic explanation for the apoptotic activity of TA

    Intramolecularly folded G-quadruplex and i-motif structures in the proximal promoter of the vascular endothelial growth factor gene

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    A polyguanine/polycytosine (polyG/polyC) tract in the proximal promoter of the vascular endothelial growth factor (VEGF) gene is essential for transcriptional activation. The guanine-rich (G-rich) and cytosine-rich (C-rich) strands on this tract are shown to form specific secondary structures, characterized as G-quadruplexes and i-motifs, respectively. Mutational analysis of the G-rich strand combined with dimethyl sulfate (DMS) footprinting, a polymerase stop assay, and circular dichroism (CD) spectroscopy revealed that the G-quadruplex containing a 1:4:1 double-chain reversal loop is the most thermodynamically stable conformation that this strand readily adopts. These studies provide strong evidence that the size of loop regions plays a critical role in determining the most favored folding pattern of a G-quadruplex. The secondary structure formed on the complementary C-rich strand was also determined by mutational analysis combined with Br2 footprinting and CD spectroscopy. Our results reveal that at a pH of 5.9 this strand is able to form an intramolecular i-motif structure that involves six C–C+ base pairs and a 2:3:2 loop configuration. Taken together, our results demonstrate that the G-quadruplex and i-motif structures are able to form on the G- and C-rich strands, respectively, of the polyG/polyC tract in the VEGF proximal promoter under conditions that favor the transition from B-DNA to non-B-DNA conformations

    Role of Endoplasmic Reticulum Stress in α-TEA Mediated TRAIL/DR5 Death Receptor Dependent Apoptosis

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    Background -- α-TEA (RRR-α-tocopherol ether-linked acetic acid analog), a derivative of RRR-α-tocopherol (vitamin E) exhibits anticancer actions in vitro and in vivo in variety of cancer types. The objective of this study was to obtain additional insights into the mechanisms involved in α-TEA induced apoptosis in human breast cancer cells. Methodology/Principal Findings -- α-TEA induces endoplasmic reticulum (ER) stress as indicated by increased expression of CCAAT/enhancer binding protein homologous protein (CHOP) as well as by enhanced expression or activation of specific markers of ER stress such as glucose regulated protein (GRP78), phosphorylated alpha subunit of eukaryotic initiation factor 2 (peIF-2α), and spliced XBP-1 mRNA. Knockdown studies using siRNAs to TRAIL, DR5, JNK and CHOP as well as chemical inhibitors of ER stress and caspase-8 showed that: i) α-TEA activation of DR5/caspase-8 induces an ER stress mediated JNK/CHOP/DR5 positive amplification loop; ii) α-TEA downregulation of c-FLIP (L) protein levels is mediated by JNK/CHOP/DR5 loop via a JNK dependent Itch E3 ligase ubiquitination that further serves to enhance the JNK/CHOP/DR5 amplification loop by preventing c-FLIP's inhibition of caspase-8; and (iii) α-TEA downregulation of Bcl-2 is mediated by the ER stress dependent JNK/CHOP/DR5 signaling. Conclusion -- Taken together, ER stress plays an important role in α-TEA induced apoptosis by enhancing DR5/caspase-8 pro-apoptotic signaling and suppressing anti-apoptotic factors c-FLIP and Bcl-2 via ER stress mediated JNK/CHOP/DR5/caspase-8 signaling.The Clayton Foundation for Research, the National Institute of Environmental Health Sciences Center Grant ES007784, the Center for Molecular and Cellular Toxicology at the University of Texas at Austin and a NIEHS/NIH Toxicology Training Grant T32 ES07247. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Biological Sciences, School o
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