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This study investigated into the antioxidant and antimicrobial properties of Origanum onites essential oil (OEO) and the application of cold atmospheric plasma (CAP) on Iranian white cheese quality during storage at 4°C for 45 days. OEO contains 28.43 ± 0.34 mg GAE/g dw and exhibited antioxidant and antimicrobial activity in in vitro tests. Iranian white cheese inoculated with Escherichia coli, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus followed by the addition of OEO at two concentrations of 2000 and 3000 ppm, and then treated by CAP for 3 and 7 min. Samples were stored at 4°C. pH, thiobarbituric acid value (TBA), L∗, a∗, b∗ color indexes, microbial count, and sensory properties of cheese samples were evaluated on days 0, 7, 15, 30, and 45. The pH value, L∗, a∗, b∗ indexes and sensorial properties of all samples decreased over time, while the TBA value and bacterial count increased. The physiochemical, microbial, and sensorial findings suggested that a combination of OEO (2500 ppm) and CAP (3 min) could be helpful in the induction of microbial growth and oxidative reactions in Iranian white cheese. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the genomic effects of vitamin D (VitD) on steroidogenesis, sperm structure, and function in mice models with artificially induced vitamin D deficiency (VDD), while maintaining calcium and phosphorus homeostasis. qRT‐PCR was utilized to measure the steady‐state RNA levels of key steroidogenic genes, including CYP11A1, CYP19A1, 17βHSDH1, 3βHSDV1, and CYP24A1, involved in VitD metabolism, in testicular extracts from mouse models with varying degrees of VDD severity. Estradiol, testosterone, luteinizing hormone (LH), and follicle‐stimulating hormone (FSH) levels were also assessed. Furthermore, testicular histomorphometric analysis and evaluation of sperm structural and functional parameters were conducted. The study reveals a linear decrease in the expression of monitored steroidogenic genes with increasing severity of VDD. Moreover, in cases of mild and moderate VDD, testicular extracts exhibited significantly reduced levels of LH, estradiol, and testosterone. VDD has substantial effects on testicular steroidogenesis, which directly impacts spermatogenesis, independent of its established role in calcium regulation. Consequently, the reduction in steroidogenesis due to VDD contributes to the diminished efficiency of testicular spermatogenesis in individuals experiencing VDD, a prevalent condition worldwide. [ABSTRACT FROM AUTHOR]

Background & Aims: Education and counseling during marriage is an opportunity to raise some issues needed by couples on the verge of marriage. This study was conducted with the aim of improving reproductive and sexual health literacy of couples on the verge of marriage. Methods: This study was a mixed‐methods participatory action research conducted based on the Find, Organize, Clarify, Understand, Select‐Plan, Do, Check, Act (FOCUS‐PDCA) model in nine steps during 2019−2020 in the city of Bandar Abbas. The Reproductive Health Literacy Scale and the Service Quality (SERVQUAL) Questionnaire were used to evaluate the interventions. Data were analyzed by SPSS version 26. A significance level of less than 0.05 was considered. Results: The mean age of women and men participating in the quantitative part of the study was 21 ± 5 and 25.84 ± 3.9 years, respectively, which was similar to their counterparts in this part of the study, and the difference in the mean scores of reproductive health literacy before and after the changes in the program showed a significant difference (p > 0.001). The study results showed that, except for the understanding dimension, most participants were at an insufficient level in other dimensions of reproductive health literacy. The result of measuring the satisfaction of service recipients indicated good satisfaction in the two dimensions of warranty and accountability, and there was a gap in empathy, assurance, and tangibility dimensions, which the biggest gap was related to the empathy dimension. Conclusion: The changes made in improving the reproductive health literacy of couples were effective, which can be taken into consideration based on the added items in the current program of providing educational services in marriage preparation classes for couples. Key points: The most expressed need of the young people on the verge of marriage was weakness in the functional level of reproductive health literacy, mainly in the field of sexual health, due to some existing sexual health education prohibitions to teenagers in schools and most families that is still among the unfulfilled needs of young people.Making changes in the usual marriage education and counseling program based on Find, Organize, Clarify, Understand, Select‐Plan, Do, Check, Act (FOCUS‐PDCA) can improve the quality of health services and increase young people's sexual and reproductive health literacy in various dimensions, particularly for developing areas with limited resources and cultural considerations. [ABSTRACT FROM AUTHOR]

Rationale: Many different structure analysis techniques are not capable of probing the heterogeneity of solution conformations. Here, we examine the ability of in‐droplet hydrogen–deuterium exchange (HDX) to directly probe solution conformer heterogeneity of a protein with mass spectrometry (MS) detection. Methods: Two vibrating capillary vibrating sharp‐edge spray ionization (cVSSI) devices have been arranged such that they generate microdroplet plumes of the analyte and D2O reagent, which coalesce to form reaction droplets where HDX takes place in the solution environment. The native HDX–MS setup has been first explored for two model peptides that have distinct structural compositions in solution. The effectiveness of the multidevice cVSSI–HDX in illustrating structural details has been further exploited to investigate coexisting solution‐phase conformations of the protein ubiquitin. Results: In‐droplet HDX reveals decreased backbone exchange for a model peptide that has a greater helix‐forming propensity. Differences in intrinsic rates of the alanine and serine residues may account for much of the observed protection. The data allow the first estimates of backbone exchange rates for peptides undergoing in‐droplet HDX. That said, the approach may hold greater potential for investigating the tertiary structure and structural transitions of proteins. For ubiquitin protein, HDX reactivity differences suggest that multiple conformers are present in native solutions. The addition of methanol to buffered aqueous solutions of ubiquitin results in increased populations of solution conformers of higher reactivity. Data analysis suggests that partially folded conformers such as the A‐state of ubiquitin increase with methanol content; the native state may be preserved to a limited degree even under stronger denaturation conditions. Conclusion: The deuterium uptake after in‐droplet HDX has been observed to correspond to some degree with peptide backbone hydrogen protection based on differences in intrinsic rates of exchange. The presence of coexisting protein solution structures under native and denaturing solution conditions has been distinguished by the isotopic distributions of deuterated ubiquitin ions. [ABSTRACT FROM AUTHOR]

The SARS‐CoV‐2 pandemic caused a public health crisis throughout the world and highlighted the need for rapid and sensitive testing as a countermeasure. A sensitive and specific biosensor platform is developed for the detection of antigen and RNA of SARS‐CoV‐2, and its variant (B1.1.529). The demonstrated biosensor platform combines unique protein catalyzed capture bioreceptors (PCCs) for antigen capture and a chimeric (RNA‐DNA) probe for RNA detection using LwaCas13a collateral cleavage activity atop graphene field effect transistors (gFETs). The reported biosensor is able to differentiate unprocessed 104 pfu m−1 samples of SARS‐CoV‐2 from Influenza and Rhinovirus. The limit of detection (LOD) calculated for SARS‐CoV‐2 antigen is 103 in buffer and 104 PFU mL−1 in 10% saliva, while LOD of ≈65 am calculated for viral RNA isolate without amplification. To provide a high reliability of detection, the role of internal and external factors with respect to gate voltage is further analyzed by Principal Component Analysis (PCA). Based on PCA analysis, the authors are able to classify the samples as pathogen positive or negative (Y > 0: Positive for pathogen, Y < 0: Negative for pathogen). The reported platform can be quickly adapted for multi‐omics and multiplexed diagnosis of continuously evolving biothreats and global pandemics. [ABSTRACT FROM AUTHOR]

Introduction: Proper toothbrush care and maintenance play an important role in oral health. This study aimed to investigate the knowledge, attitude and practice of medical and dental students regarding the maintenance and disinfection of toothbrushes. Method: This cross‐sectional descriptive study examined 824 medical and dental students of Babol University of Medical Sciences, Babol, Iran. Data were collected using a researcher‐made questionnaire and analysed using chi‐square test and independent t‐test. The level of statistical significance was considered to be <0.05. Results: Nearly 63.7% of the students had a good level of knowledge regarding toothbrush maintenance, 62.2% had a positive attitude toward toothbrush care, and 53.7% had a good practice. The mean scores of knowledge, attitude, and practice were significantly higher in dental, clinical, and female students as compared to medical, preclinical, and male students, respectively. Based on the results, about 54.3% of the students kept their toothbrushes outside the bathroom; 68% kept them vertically with the bristles upright; and 54% kept them in a separate container. Also, 50.6% of the students believed that toothbrush disinfection was necessary, while 31.9% believed that only certain groups of people needed toothbrush disinfection. Conclusion: This study indicated the moderate level of knowledge, attitude, and practice of medical and dental students in maintaining and disinfecting their toothbrushes. The students' oral health habits were also at a moderate level; therefore, further improvements seem essential. To achieve this goal, educational intervention programs need to be developed in the future. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to explore the protective role of social support and spirituality in the prevention of depression, anxiety and fatigue severity. Design: In a cross‐sectional study, 305 women of breast cancer survivors were recruited in the study. Methods: The participants answered a self‐reported the hospital anxiety and depression scale, fatigue severity scale (FSS), social support and spiritual health questionnaires. The data were analysed using a multiple linear regression model to estimate the adjusted regression coefficients. Results: A greater proportion of patients had moderate depression (62.9%) and moderate anxiety (67.3%). The higher level of social support was significantly associated with a lesser degree of depression (β=−0.05, p =.001) and anxiety (β=−0.04, p =.001), but there had been no association with the severity of fatigue score, while the association of spiritual health with depression and anxiety was not independently significant. This study highlights the importance of perceived social support in the prevention of depression and anxiety. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 nsp10–nsp16 complex is a 2′‐O‐methyltransferase (MTase) involved in viral RNA capping, enabling the virus to evade the immune system in humans. It has been considered a valuable target in the discovery of antiviral therapeutics, as the RNA cap formation is crucial for viral propagation. Through cross‐screening of the inhibitors that we previously reported for SARS‐CoV‐2 nsp14 MTase activity against nsp10–nsp16 complex, we identified two compounds (SS148 and WZ16) that also inhibited nsp16 MTase activity. To further enable the chemical optimization of these two compounds towards more potent and selective dual nsp14/nsp16 MTase inhibitors, we determined the crystal structure of nsp10–nsp16 in complex with each of SS148 and WZ16. As expected, the structures revealed the binding of both compounds to S‐adenosyl‐L‐methionine (SAM) binding pocket of nsp16. However, our structural data along with the biochemical mechanism of action determination revealed an RNA‐dependent SAM‐competitive pattern of inhibition for WZ16, clearly suggesting that binding of the RNA first may help the binding of some SAM competitive inhibitors. Both compounds also showed some degree of selectivity against human protein MTases, an indication of great potential for chemical optimization towards more potent and selective inhibitors of coronavirus MTases. PDB Code(s): 7R1T and 7R1U [ABSTRACT FROM AUTHOR]

Objective: To define the prevalence of hypothyroidism in women with chronic lower urinary tract symptoms (LUTS) and to compare the severity of each symptom between patients with hypothyroidism and controls. Subjects and methods: In this prospective observational study, we screened all adult women who came to the urology clinic between March 2017 and September 2020, and enrolled patients with chronic LUTS in the study. We assessed thyroid function. We evaluated the severity of voiding and storage urinary symptoms by the International Prostate Symptom Score. We also assessed the severity of urge urinary incontinence (UUI) and stress urinary incontinence (SUI). For between‐group analysis, we selected age‐matched cases and controls and compared them regarding the distribution and severity of urinary symptoms. Results: Seven hundred and twenty‐five women with a mean age of 51.7 ± 14.0 years were included in the final analysis. Two hundred fifty‐eight patients (35.6%) had hypothyroidism. Age‐matched case and control groups consisting of 210 patients each were selected. There was no significant difference in the severity and distribution of voiding LUTS and UUI between the study groups (P values >0.05). The severity of storage symptoms was lower in patients with hypothyroidism (P = 0.04). Sixty‐seven patients with hypothyroidism (31.9%) had SUI, which was significantly higher than controls (23.3%) (P = 0.03). Conclusion: More than one‐third of women with chronic LUTS have hypothyroidism which is much more frequent than in the general population. We also suggest a possible relationship between hypothyroidism and the severity of SUI and an inverse relationship between hypothyroidism and storage symptoms. [ABSTRACT FROM AUTHOR]

Background: Guidance during inquiry learning plays an important role in developing conceptual understanding and inquiry skills. This study analysed learner‐tutor interactions in a simulation‐assisted learning environment to investigate how tutor guidance enabled knowledge construction and fostered epistemic practice. Objectives: This research aimed to illuminate challenges learners encounter in the inquiry process and forms of guidance that support learning in both conceptual and epistemic aspects. Methods: This study uses a mixed methods approach. We analysed video recordings in which nine participants asked 72 questions and the microsequences of interactions immediately surrounding and including each question. We coded properties of each question and whether the tutors' utterances were intended to increase (upregulate) or decrease (downregulate) the complexity of the inquiry processes, and used a two‐step cluster analysis to explore groupings emerged from tutors' regulation guidance and learners' questions. Results and Conclusions: The regulatory intent of tutors' utterances depended on various characteristics of student questions. The microsequences clustered in five categories: 1) upregulated investigation and inference, 2) upregulated evidence‐based justification, 3) downregulated cognitive load, 4) downregulated procedural uncertainties, and 5) downregulated perceptual dissonance. Our findings suggest tutors offering guiding prompts should consider dual processes in the inquiry and, by strategically prompting them, strike a balance between the goals of guiding learners to discover scientific knowledge and grounding their conceptual understanding in concepts, data, and procedures. Implications: We emphasize conceptual and epistemic learning should be concurrently guided in scientific inquiry. We propose a bidirectional guidance model as a pedagogical approach to guide instructional practice. Lay Description: What is currently known about the subject matter: Rapid technological change urges schools to equip students with research and inquiry skills.Computer simulations provide an information‐rich environment for inquiry‐based learning.Guidance in inquiry learning is important for knowledge acquisition and the development of inquiry skills. What this paper adds: We illuminated challenges learners encounter in the inquiry learning process.We analysed forms of guidance that support learning in both conceptual and epistemic aspects.We identified dual processes involved in the inquiry process that have important implications.We proposed a bidirectional model for adaptive guidance in scientific inquiry. Implications of study findings for practitioners: Adaptive guidance facilitates conceptual and epistemic understanding by stimulating curiosity and reducing uncertainty in the inquiry process.Conceptual and epistemic learning need to be concurrently guided in scientific inquiry. [ABSTRACT FROM AUTHOR]

Cardiac failure, such as myocardial infarction (MI), is one of the most serious causes of mortality worldwide. MI is the sign of cardiac cell damage as a result of decreased blood oxygen level, which causes some morphological changes in the form of 12‐lead electrocardiogram (ECG) waves including T‐wave, Q‐wave, and ST‐segment. The main goal of this study is to represent vectorcardiography (VCG) as a complementary diagnostic tool of the ECG method to discriminate the various type of MI from normal cases. The system proposed in this study was analysed on the Physikalisch‐Technische Bundesanstalt diagnostic ECG database and a recorded signal database for 80 MI and 52 healthy cases. Each record consists of 15 ECG and VCG signals. In this study, tridimensional morphological features were applied to the classification and regression tree (CART) and the feedforward neural network classifier. To classify MI cases from healthy control cases of our recorded database, classification and regression tree achieved the same results when VCG features or ECG features were applied with an accuracy of 99.4%, a sensitivity of 100%, and a specificity of 98.7%. Further, by using VCG Octant features with this current method, anterior‐MI and inferior‐MI were separated with an accuracy of 98.9%, a sensitivity of 98%, and a specificity of 100%. The outcomes prove that the VCG features performed more accurately than ECG features in MI localisation. [ABSTRACT FROM AUTHOR]

The aim of this study was to prepare a porous scaffold out of 58S bioactive glass as the bare and coated with Zein to improve mechanical properties and acting as a carrier for Kaempferol controlled delivery. Porosity and morphology, mechanical properties, drug release behavior, bioactivity, cell attachment, and biodegradation of the scaffolds were evaluated accordingly. Obtained results indicated that the scaffolds coated by (7wt/v %) Zein solution, showed the highest mechanical strength (3.06 ± 0.4 MPa) and desirable porous morphology. These scaffolds could support bioactivity, cell attachment, and provide sustained drug release in the safe range of Kaempferol concentration confirmed via 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide analysis. Overall, this study showed that the Zein‐coated scaffold possesses superior properties rather than bare scaffold, and the scaffolds coated with 7wt/v % Zein solution could be considered as appropriate scaffolds for bone regeneration. [ABSTRACT FROM AUTHOR]

Increasing access to modern clinical practices concomitantly extends lifespan, ironically revealing new classes of degenerative and inflammatory diseases of later years. Here, an electronic graphene field-effect transistor (gFET) is reported, termed EV-chip, for label-free, rapid identification and quantification of exosomes (EV) associated with aging through specific surface markers, CD63 and CD151. Studies suggest that blood-derived exosomes carry specific biomolecules that can be used toward diagnostic applications of age and health. However, to observe improvements in patient outcomes, earlier detection at the point-of-care (POC) is required. Unfortunately, conventional techniques and other electronic-based platforms for exosome sensing are burdensome and inept for the POC distinction of aged blood factors. It is shown that EV-chip can quantitatively detect purified exosomes from plasma, with a limit of detection (LOD) of 2 x 104 particles mL-1 and a limit of quantification (LOQ) of 6 x 104 particles mL-1. The sensitivity and compact electronics of the EV-chip improves upon previously published electronic biosensors, making it ideal for a physician's office or a simple biological laboratory. The sensitivity, selectivity, and portability of the EV-chip demonstrate the potential of the biosensor as a powerful point-of-care diagnostic and prognostic tool for age-related diseases. [ABSTRACT FROM AUTHOR]

Given the importance of high blood pressure, it is important to control and maintain a constant blood pressure level in the normal state. The main aim of this article is to design a model predictive controller with a genetic algorithm (GA) for the regulation of arterial blood pressure. The present study is an applied cross‐sectional study. In order to do this research, studies related to designing mathematical models for blood pressure regulation and mechanical models for heart muscle and pressure sensors are investigated. Then, a model predictive controller with GA is designed for blood pressure control. All control and design operations are performed in the MATLAB software. According to the viscoelasticity of blood, transducer, and injection set, we can assume the mechanical model as Mass, Spring, and Damper. Initially, the patient's blood pressure is lower than normal, and after controlling, the patient's blood pressure returned to normal. By using a GA‐based model predictive control (MPC), mathematical validation, and mechanical model, the patient's blood pressure can be adjusted and maintained. The simulation result shows that the GA‐based MPC offers acceptable response and speed of operation and the proposed controller can achieve good tracking and disturbance rejection. [ABSTRACT FROM AUTHOR]

Background: In rodents and humans, vitamin D deficiency (VDD) is associated with altered sperm structure and function (primarily decreased motility and morphological abnormalities) that are primarily attributed to VDD‐induced hypocalcemia. However, it is suspected that VDD has much more drastic effects on mammalian spermatozoa. Objectives: The purpose of this study was to illustrate that VDD, depending on its severity and duration, can alter sperm nuclear integrity and can also lead to the loss of spermatozoa's ability to support embryonic development. Materials and methods: A mouse model of induced VDD combining the action of a vitamin D‐deficient diet, UV exposure limitation, and paricalcitol injections; a vitamin D2 analog that catabolizes endogenous vitamin D by increasing the expression of CYP24A, a member of the cytochrome P450 family, has been used to create different grades of VDD. Results: We show that the most significant sperm defect recorded concerns the integrity of the paternal nucleus, which is both decondensed and fragmented in moderate‐to‐severe VDD situations. Consistent with the known consequences of fertilization with DNA‐damaged spermatozoa, we show that paternal VDD decreases the ability of spermatozoa to optimally support fertilization and embryonic development. Discussion and Conclusion: Given the worldwide high prevalence of VDD in humans, and although obtained in an animal model, the data presented here suggest that subfertile/infertile males may benefit from VDD testing and that attempts to correct serum vitamin D levels could be considered prior to conception, either naturally or through ART. [ABSTRACT FROM AUTHOR]

Keywords: agroecosystems; biological control; coffee; ecological fitting; host shift; novel ecosystems; novel interactions; Puerto Rico EN agroecosystems biological control coffee ecological fitting host shift novel ecosystems novel interactions Puerto Rico 1 4 4 05/04/20 20200501 NES 200501 Agroecosystems are almost always by definition composed of novel assemblages of organisms from various parts of the world (Perfecto and Vandermeer [8]). Here we present what is, to our knowledge, the first case of gastropods feeding on CLR, thus shedding light on a potentially important element of autonomous biological control in coffee agroecosystems (Vandermeer et al. [13]). Agroecosystems, biological control, coffee, ecological fitting, host shift, novel ecosystems, novel interactions, Puerto Rico. [Extracted from the article]

Background: The potential toxicity that results from environmental xenobiotics is not completely known. Increasing levels of heavy metals and the use of organophosphate pesticides (OPs) and their co‐existence in the environment could be associated with an increasing incidence of male reproductive system disorders in humans and animals. Ferulago angulata is a dietary source of phenolic compounds with reported health benefits. Objective: This study was conducted to investigate whether an extract of Ferulago angulata could protect adult male NMRI mice against reproductive toxicity induced by lead acetate (PbAc), diazinon (DZN), or PbAc + DZN. Materials and methods: Adult male NMRI mice were exposed to either 0.5% PbAc in drinking water, DZN (3 mg/kg/day, intraperitoneal [i.p.] injection), or PbAc + DZN in the presence or absence of 400 mg/kg/day Ferulago angulata hydroalcoholic extract (FAE) that was administered via gavage for 6 weeks. Results: Chronic exposure to PbAc, DZN, and PbAc + DZN decreased sperm quality, sperm chromatin maturity and integrity, increased oxidative stress and lipid peroxidation, and could reduce male fertility indices. Co‐administration of FAE could reduce these negative effects. Conclusion: The Ferulago angulata extract should be considered as a useful natural extract for the treatment of male infertility, especially in males exposed to conditions which induce reproductive toxicity. [ABSTRACT FROM AUTHOR]

The metacommunity, as it evolved from Levins's metapopulation, provides a framework to consider the spatial organization of species interactions. A defining feature of metapopulations and metacommunities is that organisms (populations or communities) are connected via migration. An important result from Levins's metapopulation work – that increasing migration lowers regional extinction probability – is often incorporated into conceptions of metacommunities; however, this may not hold true for multiple interacting metapopulations (i.e. metacommunities). We report results from a metacommunity field experiment conducted with a tropical terrestrial leaf litter macro‐arthropod community. We show that migration induces regional extinctions of predators without significantly changing the predator community composition. For non‐predators we found no evidence of regional extinctions, but a significant change in community composition. Our result corroborates the findings of a prior similar metacommunity experiment with a temperate forest leaf litter community. The concordance between these experiments, even with vastly different communities, highlights the importance of considering trophic and non‐trophic community structure to understand metacommunity dynamics, and suggests a potential connection between migration rates and trophic‐specific responses in ecological communities. [ABSTRACT FROM AUTHOR]

Some trainees can arrange less-than-full-time (LTFT) training positions that allow them extra time for research, but these LTFT positions can be difficult to arrange, and often are not geographically located near the trainee's research centre. Patients benefit from receiving care in hospitals with a strong engagement in clinical research. [Extracted from the article]

A novel, stable and sensitive non‐enzymatic sensor was developed with metal‐organic frameworks (MOFs) that have attracted great attention in electrochemical sensors applications in recent years. The pore structures of MIL (Fe)‐101 and MIL (Fe)‐53 are the families of MOFs that were constructed via a simple solvothermal procedure. The 35MIL‐101(Fe)‐reduced graphene oxide nanocomposite has been used for modification of glassy carbon electrode for the determination of carbofuran (CBF) and carbaryl (CBR). The porosity of the composites increased the voltammetric responses significantly for CBF and CBR in a mixed solution that makes the simultaneous determination of both carbamate pesticides possible. Characterization of MIL (Fe)‐101 and MIL (Fe)‐53 were performed with FT‐IR, XRD, BET and SEM. Finally, the introduced sensor under the optimal conditions showed low detection limits of 1.2 and 0.5 nM within the linear ranges of 5.0–200.0 nM and 1.0–300.0 nM for CBF and CBR, respectively. The non‐enzymatic sensor was successfully used to monitoring of carbamates residue in vegetable and fruit samples. [ABSTRACT FROM AUTHOR]

Tissue and stem cell encapsulation andtransplantation were considered as promising tools in the treatment of patients with diabetes mellitus. The aim of this study was to evaluate the effect of microfluidic encapsulation on the differentiation of trabecular meshwork mesenchymal stem cells (TM‐MSC), into insulin‐producing cells (IPCs) both in vitro and in vivo. The presence of differentiated cells in microfibers (three dimensional [3D]) and tissue culture plates (TCPS; two dimensional [2D]) culture was evaluated by detecting mRNA and protein expression of pancreatic islet‐specific markers as well as measuring insulin release of cells in response to glucose challenges. Finally, semi‐differentiated cells in microfibers (3D) and 2D cultures were used to control the glucose level in diabetic rats. The results of this study showed that MSCs differentiated in alginate microfibers (fabricated by microfluidic device) express more Pdx‐1 mRNA (1.938‐fold, p‐value: 0.0425) and Insulin mRNA (2.841‐fold, p‐value: 0.0001) compared with those cultured on TCPS. Furthermore, cell encapsulation in microfluidic derived microfibers decreased the level of blood glucose in diabetic rats. The approach used in this study showed the possibility of alginate microfibers as a matrix for differentiation of TM‐MSCs (as a new source) into IPCs. In addition, it could minimize different steps in stem cell differentiation, handling, and encapsulation, which lead to loss of an unlimited number of cells. [ABSTRACT FROM AUTHOR]

Background: Reproductive toxicity of lipopolysaccharide (LPS) on spermatozoa is well established. Objective: The aim of the present study was to show the potential benefits of alpha lipoic acid (ALA) as a strong antioxidant in alleviating the reproductive toxicity of LPS. Materials and methods: Sperm cells and cumulus–oocyte complexes (COCs) were collected from healthy NMRI mice (body weights ranged from 25 to 35 g, 100 females and 200 males). Sperm cells were treated with varying doses of ALA (0.01, 0.02, and 0.04 mm) and 0.01 μg/mL of LPS for 4 h. The quality of spermatozoa (ROS production, DNA fragmentation, and spontaneous acrosome reaction), sperm fertilizability, and the consequent developmental competence of oocytes inseminated with ALA/LPS‐treated spermatozoa were recorded. Results: The results showed that 0.04 mm of ALA abrogated LPS‐reduced sperm motility, viability, ROS production, spontaneous acrosome reaction, fertilizability, and developmental competence. In addition, 0.04 mm ALA significantly reverted the negative effects of LPS on inner cell mass (ICM) cell counts, total cell number (TCM), and ratio between ICM and TCM. Discussion: Our data showed that ALA significantly could abrogate the negative effects of LPS on sperm quality and oocyte developmental competence. Therefore, ALA had the capacity for protecting sperm cells from LPS‐induced damage and ensured fertilization and developmental competency. Conclusion: These in vitro findings suggested a therapeutic role for ALA in reducing the negative effects of LPS on spermatozoa and early embryonic development. [ABSTRACT FROM AUTHOR]

Research that pertains to the molecular mechanisms involved in retinal pigment epithelial (RPE) development can significantly contribute to cell therapy studies. The effects of periocular mesenchymal cells on the expansion of RPE cells remain elusive. We have examined the possible proliferative role of hepatocyte growth factor (HGF) as a mesenchymal cell secretory factor against human embryonic stem cell derived RPE (hESC‐RPE). We found that the conditioned medium of human mesenchymal stem cells from apical papilla and/or exogenous HGF promoted proliferation of the hESC‐RPE cells as single cells and cell sheets, in addition to rabbit RPE sheets in vitro. Blockage of HGF signaling by HGF receptor inhibitor, PHA‐665752, inhibited proliferation of hESC‐RPE cells. However, differentiation of hESCs and human‐induced pluripotent stem cells to a rostral fate and eye‐field specification was unaffected by HGF. Our in vivo analysis showed HGF expression in periocular mesenchymal cells after optic cup formation in chicken embryos. Administration of HGF receptor inhibitor at this developmental stage in chicken embryos led to reduced eye size and disorganization of the RPE sheet. These findings suggested that HGF administration could be beneficial for obtaining higher numbers of hESC‐RPE cells in human preclinical and clinical trials. Dental mesenchymal stem cells originated from rostral neural crest secret hepatocyte growth factor (HGF), which promoted proliferation of hESC‐ derived RPE as a single cell and cell sheet in addition to rabbit RPE sheets in vitro. Inhibition of HGF secreted by periocular mesenchymal cells in chicken embryo led to reduced eye size and disorganization of the RPE sheets. [ABSTRACT FROM AUTHOR]

Considering to the possibility of cellular and genetic damage by the implant materials in the patient and the clinician, the safety of the biomaterials should be evaluated. The purpose of this study was to compare the cytotoxicity and genotoxicity induced by two nanocomposites, hydroxyapatite/bioactive glass (HA/BG) and fluorapatite/bioactive glass (FA/BG) in vitro. Biomaterial extracts (BMEX, 100%) were prepared by incubating 100 mg/mL of each biomaterial powder in complete culture medium (RPMI1640 + 10% FBS) for 72 h. Saos‐II cells were exposed to different concentrations of BMEXs for different periods of time and evaluated at the end of each period. According to 3–(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide assay results, both BMEXs at low concentrations (<25%) has no inhibitory effects on the cells growth. After 24 h of exposure, only HA/BG BMEX at 100% concentration showed significant cytotoxic effect. After 48 and 72 h, both HA/BG and FA/BG BMEXs showed similar cytotoxic effect at concentration higher than 75 and 50%, respectively. The results of the comet assay showed that the tail elongation, and proportionally DNA damage, increased in a dose/time dependently fashion with BMEXs exposure. Based on low and similar cytotoxicity and genotoxicity profiles on the Saos‐II cell line, it could be concluded that FA/BG, like HA/BG, could be a good candidate for further in vivo biocompatibility studies to be used in bone tissue repair. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2605–2612, 2018. [ABSTRACT FROM AUTHOR]

Abstract: This study aimed to determine the optimum concentration of trehalose in solutions used for vitrification of in vitro matured (IVM) ovine oocytes. IVM oocytes were randomly divided into four experimental (vitrified) and one control (fresh) groups. Experimental groups were treated with different concentrations (0.0, 0.25, 0.5 and 1.0 M) of trehalose. After warming, some viable oocytes were exposed to 0.25% pronase to test zona pellucida hardening, whereas the others were fertilized and cultured in vitro for 8 days to evaluate their developmental competence. Blastocysts quality was assessed by differential staining and TUNEL test. Survival and developmental rates of oocytes vitrified in the presence of 0.5 M trehalose were significantly higher than those of the other vitrified groups. Furthermore, there was a significant difference between fresh and vitrified groups in total blastocyst rate. Analysis of blastocysts quality also revealed a significant difference between the group treated with 0.5 M trehalose and other groups in terms of apoptotic index. Furthermore,zona pellucida digestion time period was longer in trehalose‐free (0.0 M) group compared to other groups. In conclusion, we found that IVM ovine oocytes vitrified in solutions containing 0.5 M trehalose are fertilization‐competent and are able to produce good‐quality blastocysts with an apoptotic index comparable to that of the fresh oocytes. Therefore, 0.5 M may be considered the optimum concentration of trehalose to be used in solutions prepared for vitrification of oocytes. [ABSTRACT FROM AUTHOR]

Abstract: Tissue regeneration is a highly coordinated process with sequential events including immune cell infiltration, clearance of damaged tissues, and immune‐supported regrowth of the tissue. Aging has a well‐documented negative impact on this process globally; however, whether changes in immune cells per se are contributing to the decline in the body’s ability to regenerate tissues with aging is not clearly understood. Here, we set out to characterize the dynamics of macrophage infiltration and their functional contribution to muscle regeneration by comparing young and aged animals upon acute sterile injury. Injured muscle of old mice showed markedly elevated number of macrophages, with a predominance for Ly6Chigh pro‐inflammatory macrophages and a lower ratio of the Ly6Clow repair macrophages. Of interest, a recently identified repair macrophage‐derived cytokine, growth differentiation factor 3 (GDF3), was markedly downregulated in injured muscle of old relative to young mice. Supplementation of recombinant GDF3 in aged mice ameliorated the inefficient regenerative response. Together, these results uncover a deficiency in the quantity and quality of infiltrating macrophages during aging and suggest that in vivo administration of GDF3 could be an effective therapeutic approach. [ABSTRACT FROM AUTHOR]

The SET1 family of proteins, and in particular MLL1, are essential regulators of transcription and key mediators of normal development and disease. Here, we summarize the detailed characterization of the methyltransferase activity of SET1 complexes and the role of the key subunits, WDR5, RbBP5, ASH2L, and DPY30. We present new data on full kinetic characterization of human MLL1, MLL3, SET1A, and SET1B trimeric, tetrameric, and pentameric complexes to elaborate on substrate specificities and compare our findings with what has been reported before. We also review exciting recent work identifying potent inhibitors of oncogenic MLL1 function through disruption of protein-protein interactions within the MLL1 complex. [ABSTRACT FROM AUTHOR]

Coupled oscillator arrays (COAs) can be used to control the phase distribution across the aperture of an array antenna in such a manner as to affect steering of the beam without the use of phase shifters. Given the various possible planar configurations of COAs, a systematic design approach is necessary. In this study, the authors present a comprehensive comparison of various configurations of planar COAs based on their sensitivity to random errors in their free running frequencies. The parameters considered are (a) the beam pointing error of the array, (b) the locking probability, (c) the side lobe level, and (d) the beam width of the radiation pattern. These results can serve as a design strategy for choosing optimal configurations of planar COAs based on the needs of each particular application. [ABSTRACT FROM AUTHOR]

In this study, the authors investigate the effect of the random free-running frequency distribution of oscillators in two-dimensional (2D) coupled oscillator arrays (COAs) on the phase error of the elements, and consequently on the beampointing angle of the array. They derive an analytic formulation for the standard deviation of the beam-pointing error (BPE) in terms of the statistical parameters of the free-running frequencies of the elements and array configuration. The results show that in order to decrease the BPE in 2D COAs, one can use COAs with a larger size (greater number of elements) and decrease the deviation of the free-running frequency of the oscillators. [ABSTRACT FROM AUTHOR]

Composites of polyvinylchloride (PVC) with single wall carbon nanotubes (SWCNTs) were prepared by plastisol curing. Scanning electron microscopy (SEM) observations revealed that appropriate dispersion of the nanotubes was achieved. The mechanical properties showed that SWCNT improved the Young's modulus and tensile strength of the PVC. The composites have higher elongation at break and toughness as well. By comparing the mechanical properties of the composites, it is found that there is a critical SWCNT loading (about 1 wt%) below which the tensile properties increase with increasing nanofiller concentration. For the composites containing 0.25-0.75 wt% of SWCNT, this situation was observed, whereas for a sample with 1 wt% SWCNT, the mechanical properties decreased due to the agglomeration of the nanotubes. Thermogravimetric analysis indicated that the SWCNT increased T5%, T10%, T50%, Tonset, and Tmax and decreased weight loss in the degradation process of the PVC. In addition, by adding SWCNT to the polymer, residual mass at 600°C increased significantly. These results are advantages for the applications of the polymer in which high mechanical properties, including high tensile modulus and toughness, and good thermal properties are needed. J. VINYL ADDIT. TECHNOL., 22:128-133, 2016. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT As one of the induced pluripotent stem cells (iPSCs) methods, spermatogonial stem cells (SSCS) extract is considered as new approach in stem cell therapy of infertility. 5-aza-2′-deoxycytidine (5-aza-dC) inhibits methyltransferase enzyme, and induces gene reprogramming; herein, the effects of SSCS extract incubation in 5-aza-dC-treated bone marrow mesenchymal stem cells (BMMSCs) has been surveyed. BMMSCs were isolated from femurs of three to four weeks old male NMRI mice, and the cells at passage three were treated with 2 µM 5-aza-dC for 72 hours. SSCs were isolated, cultured, and harvested at passage three to collect SSCS extract; BMMSCs were then incubated with SSCS extract in the three time periods: 72 hours, one week and two weeks. There were five groups: control, sham, extract, 5-aza-dC and extract-5-aza-dC. After one week of incubation, flow cytometry and real-time polymerase chain reaction (PCR) exhibited high levels of expression for β1- and α6-integrins and promyelocytic leukaemia zinc finger (PLZF) in extract and extract-5-aza-dC groups ( P < 0.05 vs. control and 5-aza-dC), and cells in these two groups had two forms of morphology, round and fusiform, similar to germ-like cells. 5-aza-dC had no significant effects during the three time periods of evaluation. These data disclose the effectiveness of SSCs extract incubation in transdifferentiation of BMMSCs into germ-like cells; this strategy could introduce a new approach for treatment of male infertility in clinic. Microsc. Res. Tech. 79:365-373, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

ABSTRACT Spermatogenesis is a highly complicated process which initiated by spermatogonial stem cells (SSCs). SSCs are the only cell type that can restore fertility in infertile recipient after SSCs transplantation. SSCs damage during cancer diagnosis and therapy and their depletion may be cause of male infertility in cancer survivors. In this review, used experimental methods regarding SSCs and testis tissue cryopreservation have been reviewed with a special focus on animal models and human which have generated the majority of data about SSCs and the cryopreservation process. Microsc. Res. Tech. 79:122-129, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

High power DC/DC converters and DC hubs are required to interconnect the high-voltage direct current (HVDC) systems with different voltage levels. Low frequency 50/60 Hz modular multilevel converters (MMCs) are known to provide better power quality, higher reliability, and lower switching losses compared to conventional two-level voltage source converters (VSCs). This study presents the optimal design of an MMC VSC for medium frequency applications suitable for DC/DC converters and DC hubs. The design aims at minimising the MMC total power loss, size, and weight as these are great importance for HVDC converters. The optimal values for the main MMC parameters including cell capacitance, arm inductance, number of cells, and operating frequency are determined using an in depth study carried out in Matlab and PSCAD. The effect of different voltage balancing methods on converter performance is also investigated. It is shown that a number of cells within the range of 20-56 with an operating frequency around 300 Hz/500 Hz for onshore/offshore applications give best trade-off between converter total loss and overall size and weight. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, plasticized poly(vinyl chloride) (PVC) composites with different nanofillers, including single-walled carbon nanotubes (SWCNTs), organoclay, TiO2, and ZnO nanoparticles, were prepared, and their effects on plasticizer migration were investigated. Scanning electron micrographs revealed the dispersion quality of the nanofillers in the polymer matrix. It had a significant influence on the performance of the nanofillers in the process of plasticizer migration. Migration and exudation tests showed that the nanofillers could efficiently hinder plasticizer migration. On the basis of these results, we concluded that carbon nanotubes were the best antimigration agent in the plasticized system. This was ascribed to the high aspect ratio of the SWCNTs and the good interactions between them and the plasticizer. Also, TiO2 nanoparticles showed a better performance compared to the ZnO nanoparticles. This was due to the more homogeneous dispersion of the TiO2 in the polymer matrix and the higher surface area of the particles. The differential scanning calorimetry thermograms were in good agreement with the migration tests. The lowest change in the glass-transition temperature was observed for the composite filled with SWCNTs. This indicated that a lower amount of the plasticizer migrated from PVC. The thermogravimetric analysis curves showed that the incorporation of the nanofillers improved the thermal stability of the PVC. The results could be useful for determining the efficiency of plasticized PVC in applications. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42559. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, to investigate the effect of functionalized carbon nanotubes on the thermal and mechanical properties of the poly(vinyl butyral) (PVB) resin, PVB/functionalized single-walled carbon nanotube (f-SWCNT) composites were fabricated by a solution casting method. The functionalized nanotubes were prepared by acid treatment. The formation of oxygen-containing functional groups on the surface of the nanotubes was confirmed by Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy (SEM) measurements. SEM analysis also showed that the nanotubes were dispersed well in the PVB matrix. The thermal stability of the composites were investigated with thermogravimetric analysis, and the results show better stability for PVB in the presence of a very low content of the f-SWCNTs. The prepared composites exhibited a significant increase in the temperature of degradation at 50 wt % loss and also in the onset temperature and decomposition temperature at the maximum rate of weight loss of butyral degradation. A significant enhancement in the mechanical properties was also achieved for these prepared composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40481. [ABSTRACT FROM AUTHOR]

We propose a novel type of one-dimensional photonic crystal composed of stack of alternating layers of dielectric and graphene sheets. Based on discontinuity in derivative of electric field component in the boundaries between graphene sheets and dielectric layers, analytical dispersion relations of this structure, for both TE and TM polarizations, is obtained. A comparison between bandgaps created in this structure and ones created in a one-dimensional metallic photonic crystal, for normal incidence is made. It is concluded that a novel type of bandgap appears in this structure due to dissipative feature of graphene which we call it graphene absorption bandgap. Moreover, in comparison with the one-dimensional metallic photonic crystal, the electromagnetic waves penetrate in this structure with much lower damping. Finally, since the chemical potential of graphene sheets can be modified by gate voltage, the bandgaps in the considered structure can be tuned by the gate voltage (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]