Iterative Approximate Solutions of Kinetic Equations for Reversible Enzyme Reactions

We study kinetic models of reversible enzyme reactions and compare two techniques for analytic approximate solutions of the model. Analytic approximate solutions of non-linear reaction equations for reversible enzyme reactions are calculated using the Homotopy Perturbation Method (HPM) and the Simple Iteration Method (SIM). The results of the approximations are similar. The Matlab programs are included in appendices.Comment: 28 pages, 22 figure

Epidemiological Study of Breast Cancer in Erbil, Kurdistan Region

Breast cancer is the most diagnosed cancer and the second leading cause of cancer death among women in the world. Compared to some other regions in the world, amount of information available about breast cancer epidemiology in the Kurdistan Region of Iraq is scarce. This study is an attempt to enrich our knowledge about different epidemiological aspects of breast cancer in the region since epidemiological studies contribute quite significantly to the current knowledge of environmental and genetic risk factors and to the current treatment strategies for breast cancer. In addition, studies has shown that the past and ongoing research has a massive implication in improving the outcome of this common disease. This work takes all women diagnosed with breast cancer at Nanakaly Hospital in Erbil, Iraq as sample of the study. Patient characteristics were captured then statistical analysis was performed on these data sets. The majority of patients were found to be city dwellers and about 46% were diagnosed at stage II and 40% at stage III. The vast majority of cases tested positive for hormone receptors but negative for HER2

Induction of Cellular Senescence by Doxorubicin Is Associated with Upregulated miR-375 and Induction of Autophagy in K562 Cells

BACKGROUND: Cellular senescence is a specialized form of growth arrest that is generally irreversible. Upregulated p16, p53, and p21 expression and silencing of E2F target genes have been characterized to promote the establishment of senescence. It can be further aided by the transcriptional repression of proliferation-associated genes by the action of HP1γ, HMGA, and DNMT proteins to produce a repressive chromatin environment. Therefore, senescence has been suggested to functions as a natural brake for tumor development and plays a critical role in tumor suppression and aging. METHODOLOGY/PRINCIPAL FINDINGS: An in vitro senescence model has been established by using K562 cells treated with 50 nM doxorubicin (DOX). Since p53 and p16 are homozygously deleted in the K562 cells, the DOX-induced senescence in K562 cells ought to be independent of p53 and p16-pRb pathways. Indeed, no change in the expression of the typical senescence-associated premalignant cell markers in the DOX-induced senescent K562 cells was found. MicroRNA profiling revealed upregulated miR-375 in DOX-induced senescent K562 cells. Treatment with miR-375 inhibitor was able to reverse the proliferation ability suppressed by DOX (p<0.05) and overexpression of miR-375 suppressed the normal proliferation of K562 cells. Upregulated miR-375 expression was associated with downregulated expression of 14-3-3zeta and SP1 genes. Autophagy was also investigated since DOX treatment was able to induce cells entering senescence and eventually lead to cell death. Among the 24 human autophagy-related genes examined, a 12-fold increase of ATG9B at day 4 and a 20-fold increase of ATG18 at day 2 after DOX treatment were noted. CONCLUSIONS/SIGNIFICANCE: This study has demonstrated that in the absence of p53 and p16, the induction of senescence by DOX was associated with upregulation of miR-375 and autophagy initiation. The anti-proliferative function of miR-375 is possibly exerted, at least in part, by targeting 14-3-3zeta and SP1 genes

Distribution of red cell antigens according to ABO, Rh and other rare blood group systems in Kurdish ethnicity

Background: Among more than 30 blood group systems, nine of them namely ABO, Rh, Kell, Kidd, Duffy, MNS, P, Lewis and Lutheran are considered to be clinically significant. The distributions of these blood groups are different between populations across the world. Studies about the frequency of blood groups in Kurdish ethnicity are very limited in the literature. Objectives: to explore the distribution of red cell antigens and phenotypes of various blood groups among Kurdish population using different systems. Materials and Methods: five thousand blood donors attending the central blood bank of Sulaymaniyah province were randomly selected and tested for ABO and Rh antigens (D, C, c, E, & e) by using tube method. 500 donors were randomly selected and further analyzed using other blood group systems. Results: In the ABO system, the most common phenotype was O (37%), followed by A (32.6%), B (22.8%) and AB (7.6%). Among the Rh blood group antigens, e was the most common (95.2%) followed by D (91.3%), C (74.8%), c (69.4%), and E (30.6%) with DCe/DCe(R1R1) and dce/dce(rr) being the most common phenotypes among Rh-D+ve and Rh-D-ve groups, respectively. The most common phenotypes for other blood systems were as follow; Kell(K-k+,94%), Kidd(jk a+b+,44.5%), Duffy(fy a+b+,45%), Lutheran(Lu a-b+,92%), Lewis(Le a-b+,54.5%), P(P1,76%), MNS(M+N+S-s+,40%) Conclusion: the various red cell antigens recorded by different blood grouping systems in this study was intermediate between the European and Asian countries with some specificity to the Kurds population reflecting the distinct geographical area and preserved ethnic background of the Kurds in the region

Preparation and characterisation of sustainable wood plastic composites extracted from municipal solid waste

open access articleMunicipal solid waste (MSW) contains plastic waste that can be used as a sustainable green substitute to reduce oil footprints, CO2 emissions, and environmental pollution. This study aims to recycle plastic waste by manufacturing wood-plastic composites and to improve its mechanical properties by using additives, coupling agents, and lubricants. These composites are prepared by mixing 40–70% of wood flour with 20–25% of a polymer matrix. Wood was degraded at 220 C, and then the composites were processed at 50 C. The manufacturing process carried out in the study involved wood waste meshing, drying, shredding, drying, trimming, filling, blending, compounding, and extrusion moulding. The compounding of composites was accomplished in twin-screw extruders. Once the mixture was uniformly mixed, its final shape was given by a two-step extrusion moulding. Previously, researchers aimed at enhancing the mechanical properties of the composites, but our research focus was to improve their durability for different industrial applications. The results suggest that the impact strength is 17 MPa with 50% of wood powder ratio while the maximum value for the tensile strength is 32.5 MPa. About 50% of an increase in wood powder resulted in 8.1% bending strength increase from 26.1 to 32.8 MPa. Reducing the plastic matrix and the woodparticles water swelling ratio resulted in better mechanical properties. The wood species also affected the mechanical properties with their excellent dimensional stability and less variability. A high proportion of wood fibre tends to increase its steady-state torque and viscosity. The mechanical properties against different wood-flour proportions indicate that composite materials exhibit superior water swelling behaviour and extrusion quality

Long-term patient-reported outcomes for open surgery of the triangular fibrocartilage complex

Aims Studies on long-term patient-reported outcomes after open surgery for triangular fibrocartilage complex (TFCC) are scarce. Surgeons and patients would benefit from self-reported outcome data on pain, function, complications, and satisfaction after this surgery to enhance shared decision-making. The aim of this study is to determine the long-term outcome of adults who had open surgery for the TFCC. Methods A prospective cohort study that included patients with open surgery for the TFCC between December 2011 and September 2015. In September 2020, we sent these patients an additional follow-up questionnaire, including the Patient-Rated Wrist Evaluation (PRWE), to score satisfaction, complications, pain, and function. Results A total of 113 patients were included in the analysis. At ≥ 60 months after an open TFCC reinsertion, we found a mean PRWE total score of 19 (SD 21), a mean PRWE pain score of 11 (SD 11), and a PRWE function score of 9 (SD 10). The percentage of patients obtaining minimum clinically important difference rose from 77% at 12 months to 83% at more than 60 months (p < 0.001). Patients reported fewer complications than surgeons, and overall complication rate was low. Conclusion Outcomes of patient-reported pain, function scores, and satisfaction are improved five years after open surgery for the TFCC