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Background: Clostridioides difficile infection (CDI) is the main etiologic agent of antibiotic-associated diarrhea. CDI contributes to gut inflammation and can lead to disruption of the intestinal epithelial barrier. Recently, the rate of CDI cases has been increased. Thus, early diagnosis of C. difficile is critical for controlling the infection and guiding efficacious therapy., Approach: A search strategy was set up using the terms C. difficile biomarkers and diagnosis. The found references were classified into two general categories; conventional and advanced methods., Results: The pathogenicity and biomarkers of C. difficile, and the collection manners for CDI-suspected specimens were briefly explained. Then, the conventional CDI diagnostic methods were subtly compared in terms of duration, level of difficulty, sensitivity, advantages, and disadvantages. Thereafter, an extensive review of the various newly proposed techniques available for CDI detection was conducted including nucleic acid isothermal amplification-based methods, biosensors, and gene/single-molecule microarrays. Also, the detection mechanisms, pros and cons of these methods were highlighted and compared with each other. In addition, approximately complete information on FDA-approved platforms for CDI diagnosis was collected., Conclusion: To overcome the deficiencies of conventional methods, the potential of advanced methods for C. difficile diagnosis, their direction, perspective, and challenges ahead were discussed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The locking compression plate (LCP) and screw sets are widely used as internal fixator assemblies to treat long bone fractures. However, the surgeon's critical challenge is choosing the implant set (plate and screws) for each patient. The present study introduces a parametrized simulation-based optimization algorithm for determining an LC system with the best bone-implant stability. For this purpose, a three-dimensional fractured bone supported by an LC system was generated, and the discrete genetic optimization approach was utilized to design the optimum implant. Initially, an algorithm was developed to optimize the optimum layouts for different numbers of screws. For the middle third transverse fracture, six screws were selected as the optimal number of the screws. In a second stage, the model was run to determine the best LC plate dimensions for desired fractured bones. Finally, optimal plates were identified for simple middle third transverse, 60° middle third oblique, and distal third transverse femoral fractures. The results of these simulations and those for other fracture types can be exploited to achieve improved surgical outcomes by selecting proper implants and screws configurations., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Shape transformations in biological membranes are crucial in a variety of cellular processes such as transport in the Golgi apparatus and endoplasmic reticulum, shaping the cell organelles and signaling in neuronal synapses. Dynamic analysis of lipid bilayer membranes is popular among researchers as valuable information about cell functions can be retrieved. There are several limitations in experimental tests and simulations such as computational and implementation cost while in theoretical studies, different phenomena can be modeled and the effect of each parameter can be investigated. In this paper, a continuum model including elastic energies and dissipation functions is utilized with energy approach to obtain the governing equations of an enclosed lipid bilayer membrane. The governing equations are solved numerically for vesicles initially disturbed and the relaxation dynamics is studied. The stationary shape of the vesicles for different values of reduced volume and reduced area difference is obtained to explore the phase diagram and verify the governing equations. Then, the density asymmetry in bilayers caused by the change in the density or the equilibrium density of the outer monolayer is studied. This leads to the formation of buds, tubules, and pearls. This can be observed in the recruitment of proteins to the outer monolayer or pH gradients of the environment of a vesicle. The effect of density difference and curvature on creation and growth of tubules are investigated. An interesting metastable state in the adsorption of the final bud due to the increase in the density of the outer monolayer is observed in which the shape of the vesicle is almost unchanged. A prolate vesicle relaxes toward an oblate or a stomatocyte vesicle when the equilibrium density of the outer monolayer increases., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Endometrial CD146 + cells were purified, using magnetic activated cell sorting, and then embedded and cultured in a collagen-matrigel scaffold on top of myometrial smooth muscle cells for 10 days. At the end of culture period, the differentiation and formation of the epithelial-like cells were confirmed by morphological and ultrastructural evaluations, and analysis by reverse transcription polymerase chain reaction of the specific expression of genes: osteopontin (SPP1), matrix metalloproteinase 2, zonula occludens 1, laminin alpha 2 and collagen type IV; and by western blotting of CD9 protein. The results showed that the human endometrial mesenchymal CD146 + cells were able to produce endometrial glandular tube-like structures in vitro. Ultrastructural observation revealed some projections on the apical surfaces, appearance of basal lamina-like structures on the basal surface, and tight junctions and desmosomes on the lateral surfaces of the epithelial-like cells. The expression of studied genes at RNA level and CD9 at protein level confirmed the formation of endometrial epithelial-like cells. This culture system may have potential applications in cell therapy and in studies on human embryo implantation., (Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Background: The effects of prenatal food and micronutrient supplementation on maternal micronutrient status are not well known., Objective: We compared the efficacy and effectiveness of 3 different micronutrient supplements on maternal micronutrient status when combined with food supplementation., Methods: In the MINIMat (Maternal and Infant Nutrition Intervention, Matlab) trial in Bangladesh, 4436 pregnant women were randomly assigned to daily intake of 3 types of micronutrient capsules: 30 mg Fe and 400 μg folic acid (Fe30F), 60 mg Fe and 400 μg folic acid (Fe60F), or multiple micronutrient supplements (MMNs) combined with early (week 9 of pregnancy) or usual (week 20 of pregnancy) food supplementation in a 2 by 3 factorial design. Plasma concentrations of vitamin B-12, folate, ferritin, and zinc were analyzed before the start of micronutrient supplementation (week 14) and at week 30 of pregnancy in 641 randomly selected women. An electronic monitoring device was used to measure the number of capsules taken. The effectiveness of food and micronutrient regimens as well as efficacy per capsule in maternal micronutrient status were analyzed by ANOVA and general linear models., Results: At week 30 of pregnancy, women in the MMN group had higher geometric mean concentrations of vitamin B-12 than women in the Fe60F group (119 compared with 101 pmol/L, respectively); no other differences in effectiveness of micronutrient and food regimens were observed. A dose-response relation between the number of capsules taken and concentrations of folate and ferritin was observed for all micronutrient supplements. Fe30F had lower efficacy per capsule in increasing ferritin concentrations within the first tertile of capsule intake than did Fe60F and MMNs. Because ferritin reached a plateau for all types of micronutrient supplements, there was no difference between the regimens in their effectiveness., Conclusion: Compared with Fe60F, MMNs produced higher maternal vitamin B-12 and similar ferritin and folate concentrations in Bangladeshi women. The MINIMat trial was registered at isrctn.org as ISRCTN16581394., Competing Interests: 2Author disclosures: S Ziaei, A Rahman, R Raqib, B Lönnerdal, and E-C Ekström, no conflicts of interest.

In this paper, the effects of cell geometry and relative density on the high-cycle fatigue behavior of Titanium scaffolds produced by selective laser melting and electron beam melting techniques were numerically investigated by finite element analysis. The regular titanium lattice samples with three different unit cell geometries, namely, diamond, rhombic dodecahedron and truncated cuboctahedron, and the relative density range of 0.1-0.3 were analyzed under uniaxial cyclic compressive loading. A failure event based algorithm was employed to simulate fatigue failure in the cellular material. Stress-life approach was used to model fatigue failure of both bulk (struts) and cellular material. The predicted fatigue life and the damage pattern of all three structures were found to be in good agreement with the experimental fatigue investigations published in the literature. The results also showed that the relationship between fatigue strength and cycles to failure obeyed the power law. The coefficient of power function was shown to depend on relative density, geometry and fatigue properties of the bulk material while the exponent was only dependent on the fatigue behavior of the bulk material. The results also indicated the failure surface at an angle of 45° to the loading direction., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Effect of solid distribution between edges and vertices of three-dimensional cellular solid with an open-cell structure was investigated both numerically and experimentally. Finite element analysis (FEA) with continuum elements and appropriate periodic boundary condition was employed to calculate the elastic properties of cellular solids using tetrakaidecahedral (Kelvin) unit cell. Relative densities between 0.01 and 0.1 and various values of solid fractions were considered. In order to validate the numerical model, three scaffolds with the relative density of 0.08, but different amounts of solid in vertices, were fabricated via 3-D printing technique. Good agreement was observed between numerical simulation and experimental results. Results of numerical simulation showed that, at low relative densities (<0.03), Young׳s modulus increased by shifting materials away from edges to vertices at first and then decreased after reaching a critical point. However, for the high values of relative density, Young׳s modulus increased monotonically. Mechanisms of such a behavior were discussed in detail. Results also indicated that Poisson׳s ratio decreased by increasing relative density and solid fraction in vertices. By fitting a curve to the data obtained from the numerical simulation and considering the relative density and solid fraction in vertices, empirical relations were derived for Young׳s modulus and Poisson׳s ratio., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objective: Low maternal serum lipid and high maternal serum lipid have both been associated with some complications in pregnancy. The lipid profiles in pregnancies complicated by small for gestational age (SGA) or hypertension disorders have been compared with those of normal pregnancies., Method: In a prospective study, 900 pregnant women between 13 and 23weeks of pregnancy were studied. Primarily, serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, were measured. Ultimately, the serum lipid levels at 13-23weeks of pregnancies were compared between the women who later suffered from hypertension disorders or SGA and the matched women with normal pregnancies., Results: At 13-23weeks of pregnancy, the mean triglyceride levels were significantly higher in the women who later experienced preeclampsia when compared with normal, matched pregnancies with an appropriate weight for gestational age and women who had gestational hypertension (p=0.001 and p=0.014, respectively). Also, triglyceride levels were significantly higher in women with neonates with large for gestational age (LGA) in comparison with those who gave birth to neonates with SGA (p=0.012) and with uncomplicated matched pregnant women who gave birth to neonates with weight >10th and <90th percentile for their gestational age (p=0.007)., Conclusion: Only the levels of TG and not any other lipids evaluated were found to be different in pregnancies complicated by preeclampsia when compared to pregnancies complicated by SGA., (Copyright © 2012 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.)

The effects of the geometrical asymmetric related to tip position as a concentrated mass, on the sensitivity of all three vibration modes, lateral excitation (LE), torsional resonance (TR) and vertical excitation (VE), of an atomic force microscopy (AFM) microcantilever have been analyzed. The effects of the tip mass and its position are studied to report the novel results to estimating the vibration behavior of AFM such as resonance frequency and amplitude of the microcantilever. In this way, to achieve more accurate results, the coupled motion in all three modes is considered. In particular, it is investigated that performing the coupled motion in analysis of AFM microcantilever is almost necessary. It is shown that the tip mass and its position have significant effects on vibrational responses. The results show that considering the tip mass decreases the resonance frequencies particularly on high-order modes. However, dislocating of tip position has an inverse effect that causes an increase in the resonance frequencies. In addition, it has been shown that the amplitude of the AFM microcantilever is affected by the influences of tip and its position. These effects are caused by the interaction between flexural and torsional motion due to the moment of inertia of the tip mass.

Cellular multi-drug resistance (MDR), which often develops in cancer cells of patients subjected to anti-cancer treatment, remains a significant barrier to successful cancer therapy. One of the principal causes of cellular MDR development is an increased expression of ABC-transporter genes such as mdr1 and Bcrp1/Abcg2. Despite many years of intensive research, the natural biological role of mdr1 in the context of cancer has remained elusive. Some hints about this role came, however, from an observation that P-gp, the mdr1 encoded protein, is expressed widely in stem cells and from the discovery that P-gp possesses an anti-apoptotic activity independently of exogenous drug application. Here, we discuss our own and other groups' recently published works and propose an integrated view of mdr1 and Bcrp1/Abcg2 activity during tissue regeneration in normal tissues as part of a stress-induced regeneration genetic program and in cancerous tissues in response to cancer therapy.

This was a comparative study of side effects and acceptability of low-dose pills administered by the oral and vaginal rout. In an experimental clinical trial study, undesirable side effects of nausea, dysmenorrhea, breast tenderness, gastrointestinal disorders, vertigo, headache, and breakthrough bleeding (BTB) were studied. The participants of the case and the control groups were the same women. The side effects were compared in 143 women using contraceptive pill containing 150 microg levonorgestrel and 30 microg ethinyl estradiol by vaginal and oral route. The efficacy and acceptability were evaluated. The side effects among the patients who used the contraceptive pills orally were significantly higher than among those who used the vaginal route (p < 0.0001). BTB occurred more often with the oral route, but there was no significant difference between their incidences (p = 0.267). Most participants in this study expressed a high level of acceptability with the vaginal route. There was only one unwanted pregnancy, which occurred when the participant used the contraceptive pill vaginally, but used it incorrectly. Using the contraceptive pill administered by vaginal route is a safe method with fewer side effects and more acceptability when compared with the oral route.