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Open AccessArticle

Effect of Yoga versus Light Exercise to Improve Well-Being and Promote Healthy Aging among Older Adults in Central India: A Study Protocol for a Randomized Controlled Trial

by

Thomas Daniel Rajasekhar ,

Parag Dhoble ,

Ashish Sharma ,

Juhi Suliya ,

Dhanashree Apsingekar ,

Maria Jirwe ,

Vijay Mahadik and

Geriatrics 2019, 4(4), 64; https://doi.org/10.3390/geriatrics4040064 (registering DOI) - 16 Nov 2019

Abstract

Background: Aging is a natural process associated with many functional and structural changes. These changes may include impaired self-regulation, changes in tissues and organs. Aging also affects mood, physical status and social activity. There are adverse changes in cognitive behavior, perceived sensation and [...] Read more.

Background: Aging is a natural process associated with many functional and structural changes. These changes may include impaired self-regulation, changes in tissues and organs. Aging also affects mood, physical status and social activity. There are adverse changes in cognitive behavior, perceived sensation and thinking processes. Regular physical activity can alleviate many health problems; yet, many older adults are inactive. Yoga is one of the scientific and popular lifestyle practice considered as the integration of mind, body and soul. Results of previous studies reported positive effects of yoga on multiple health outcomes in elderly. However, there is scarcity of scientific information where yoga’s effect is examined on over well-being and on multiple health outcomes simultaneously in elderly. This protocol describes methods for a 12-week yoga-based intervention exploring the effects of yoga on well-being in physically inactive elderly living in community. Methods and analysis: This two group parallel single blind randomized controlled trial that will be conducted at a designated facility of R.D. Gardi Medical College, Ujjain, Madhya Pradesh, Central India. A 12-week 60-min yoga intervention three times weekly is designed. Comparison group participants will undergo a 60-min program comprising light exercise focusing on conventional stretching to improve mobility. After screening, 144 participants aged 60–80 years will be recruited. The primary outcome is subjective well-being. Secondary outcomes include mobility, fall risk, cognition, anxiety and depression, mood and stress, sleep quality, pain, physical activity/sedentary behavior and cardio-metabolic risk factors. Assessments will be conducted at baseline (0 week), after the intervention (12+1 week) and at follow-up (36+1 week). Intention-to-treat analyses with mixed linear modeling will be applied. Discussion: Through this trial, we aim to determine whether elderly people in the intervention group practicing yoga show more favorable primary (well-being) and secondary outcomes than those in the light exercise focusing on conventional stretching group. We assume that yoga may be practiced to maintain health, reduce particular symptoms commonly associated with skeletal pain, assist in pain relief and enhance well-being. We anticipate that practicing yoga will improve well-being and mental health and may lead to significant improvement in depression, pain and sleep quality.Ethics and dissemination: This study is approved by the Institutional Ethics Committee of R.D. Gardi Medical College, Ujjain, IEC Ref No. 09/2018. All participants would be provided with written and verbal information about the purpose of the project and would be free to withdraw from the study at any time. Refusal to participate in the study would not have any negative consequences. Confidentiality of the information of each participant would be ensured. Knowledge obtained would be disseminated to stakeholders through workshops, meetings and relevant scientific conferences.Trial Registration: The trial is prospectively registered with the Indian Council of Medical Research Trial Registry CTRI/2018/07/015051. Full article

(This article belongs to the Section Healthy Aging)

Open AccessArticle

Agglomeration Economies: An Analysis of the Determinants of Employment in the Cities of Ecuador

by

Tania Paola Torres-Gutiérrez ,

Ronny Correa-Quezada ,

José Álvarez-García and

María de la Cruz del Río-Rama

Symmetry 2019, 11(11), 1421; https://doi.org/10.3390/sym11111421 (registering DOI) - 16 Nov 2019

Abstract

The objective of this investigation is to study the role of agglomeration economies (manufacturing) in urban employment growth, as a proxy for economic growth, between 1980 and 2010 in Ecuador. The three measures of agglomeration-specialization, diversity, and density-are tested to determine their eﬀect [...] Read more.

The objective of this investigation is to study the role of agglomeration economies (manufacturing) in urban employment growth, as a proxy for economic growth, between 1980 and 2010 in Ecuador. The three measures of agglomeration-specialization, diversity, and density-are tested to determine their eﬀect on employment growth in industries. The empirical analysis is based on firm- and city-level data from manufacturing activities. A model is proposed to estimate the effect of agglomeration economies on the growth of employment and a regression is conducted using instrumental variables. In particular, the two-stage least squares (2SLS) estimator is used. We conclude that localization economies measured by a specialization index have a positive impact on the growth of employment in the period analyzed. The results are similar to those obtained by other work carried out both in developed and developing countries. Full article

Open AccessArticle

Mice Microbiota Composition Changes by Inulin Feeding with a Long Fasting Period under a Two-Meals-Per-Day Schedule

by

Yijin Lyu ,

Koki Hama and

Shigenobu Shibata

Nutrients 2019, 11(11), 2802; https://doi.org/10.3390/nu11112802 (registering DOI) - 16 Nov 2019

Abstract

Water-soluble dietary fiber is known to modulate fecal microbiota. Although there are a few reports investigating the effects of fiber intake timing on metabolism, there are none on the effect of intake timing on microbiota. Therefore, in this study, we examined the timing [...] Read more.

Water-soluble dietary fiber is known to modulate fecal microbiota. Although there are a few reports investigating the effects of fiber intake timing on metabolism, there are none on the effect of intake timing on microbiota. Therefore, in this study, we examined the timing effects of inulin-containing food on fecal microbiota. Mice were housed under conditions with a two-meals-per-day schedule, with a long fasting period in the morning and a short fasting period in the evening. Then, 10–14 days after inulin intake, cecal content and feces were collected, and cecal pH and short-chain fatty acids (SCFAs) were measured. The microbiome was determined using 16S rDNA sequencing. Inulin feeding in the morning rather than the evening decreased the cecal pH, increased SCFAs, and changed the microbiome composition. These data suggest that inulin is more easily digested by fecal microbiota during the active period than the inactive period. Furthermore, to confirm the effect of fasting length, mice were housed under a one-meal-per-day schedule. When the duration of fasting was equal, the difference between morning and evening nearly disappeared. Thus, our study demonstrates that consuming inulin at breakfast, which is generally after a longer fasting period, has a greater effect on the microbiota. Full article

(This article belongs to the Special Issue Nutrition, Microbiota and Noncommunicable Diseases)

Open AccessArticle

Socio-Economic Impacts of Cyclone Aila on Migrant and Non-Migrant Households in the Southwestern Coastal Areas of Bangladesh

by

Rizwana Subhani and

Mokbul Morshed Ahmad

Geosciences 2019, 9(11), 482; https://doi.org/10.3390/geosciences9110482 (registering DOI) - 16 Nov 2019

Abstract

In 2009, the tropical cyclonic storm Aila hit 11 southwestern coastal districts in Bangladesh, which triggered migration. Many studies were conducted on the impact of Aila on southwestern coastal communities; however, no comparative study was done on migrant and non-migrant households. Therefore, this [...] Read more.

In 2009, the tropical cyclonic storm Aila hit 11 southwestern coastal districts in Bangladesh, which triggered migration. Many studies were conducted on the impact of Aila on southwestern coastal communities; however, no comparative study was done on migrant and non-migrant households. Therefore, this article set out to assess the impact of cyclone Aila on the socio-economic conditions of migrant and non-migrant households. The households that could not cope with the impact, resulting in at least one household member having to migrate to seek an alternative source of income, were considered migrant households. On the other hand, non-migrant households were considered as those where no one migrated. The unit of analysis was the households. The research was conducted in the Koyra and Shymnagar sub-districts of Khulna and Satkhira, respectively. Mixed-method analysis was carried out using quantitative data collected from 270 households through a survey and qualitative data through 2 focus group discussions, 12 key informant interviews, and informal discussions. Data were analyzed through a comparative analysis of the migrant and non-migrant households. The findings showed that migrant households were better equipped to recover from losses in terms of income, housing, food consumption, and loan repayments than non-migrant households. It can be argued that the options of migration or shifting livelihood are better strategies for households when dealing with climatic events. Furthermore, the outcome of this research could contribute to the growing body of knowledge in an area where there are evident gaps. The findings could support policymakers and researchers to understand the impacts of similar climatic events, as well as the necessary policy interventions to deal with similar kinds of climatic events in the future. The study could be useful for developing and refining policies to recover from losses as a result of the same types of climatic events. Full article

(This article belongs to the Section Natural Hazards)

Open AccessArticle

Size Matters: New Zintl Phase Hydrides of REGa (RE = Y, La, Tm) and RESi (RE = Y, Er, Tm) with Large and Small Cations

by

Anton Werwein ,

Thomas C. Hansen and

Holger Kohlmann

Crystals 2019, 9(11), 600; https://doi.org/10.3390/cryst9110600 (registering DOI) - 16 Nov 2019

Abstract

Many Zintl phases exhibiting a CrB type structure form hydrides. Systematic studies of AeTtH_x(Ae = Ca, Sr, Ba; Tt = Si, Ge, Sn), LnTtH_x (Ln = La, Nd; Tt = Si, Ge, Sn), and LnGaH [...] Read more.

Many Zintl phases exhibiting a CrB type structure form hydrides. Systematic studies of AeTtH_x(Ae = Ca, Sr, Ba; Tt = Si, Ge, Sn), LnTtH_x (Ln = La, Nd; Tt = Si, Ge, Sn), and LnGaH_x (Ln = Nd, Gd) showed the vast structural diversity of these systems. Hydrogenation reactions on REGa (RE = Y, La, Tm) and RESi (RE = Y, Er, Tm) were performed in steel autoclaves under hydrogen pressure up to 5 MPa and temperatures up to 773 K. The products were analyzed by X-ray and neutron powder diffraction. RESi (RE = Y, Er, Tm) form hydrides in the C-LaGeD type. LaGaD_1.66is isostructural to NdGaD_1.66and shows similar electronic features. Ga-D distances (1.987(13) Å and 2.396(9) Å) are considerably longer than in polyanionic hydrides and not indicative of covalent bonding. In TmGaD_0.93(2) with a distorted CrB type structure deuterium atoms exclusively occupy tetrahedral voids. Theoretical calculations on density functional theory (DFT) level confirm experimental results and suggest metallic properties for the hydrides. Full article

(This article belongs to the Section Crystalline Materials)

Open AccessFeature PaperArticle

A Deep Learning Based Transmission Algorithm for Mobile Device-to-Device Networks

by

Tae-Won Ban and

Woongsup Lee

Electronics 2019, 8(11), 1361; https://doi.org/10.3390/electronics8111361 (registering DOI) - 16 Nov 2019

Abstract

Recently, device-to-device (D2D) communications have been attracting substantial attention because they can greatly improve coverage, spectral efficiency, and energy efficiency, compared to conventional cellular communications. They are also indispensable for the mobile caching network, which is an emerging technology for next-generation mobile networks. [...] Read more.

Recently, device-to-device (D2D) communications have been attracting substantial attention because they can greatly improve coverage, spectral efficiency, and energy efficiency, compared to conventional cellular communications. They are also indispensable for the mobile caching network, which is an emerging technology for next-generation mobile networks. We investigate a cellular overlay D2D network where a dedicated radio resource is allocated for D2D communications to remove cross-interference with cellular communications and all D2D devices share the dedicated radio resource to improve the spectral efficiency. More specifically, we study a problem of radio resource management for D2D networks, which is one of the most challenging problems in D2D networks, and we also propose a new transmission algorithm for D2D networks based on deep learning with a convolutional neural network (CNN). A CNN is formulated to yield a binary vector indicating whether to allow each D2D pair to transmit data. In order to train the CNN and verify the trained CNN, we obtain data samples from a suboptimal algorithm. Our numerical results show that the accuracies of the proposed deep learning based transmission algorithm reach about 85%∼95% in spite of its simple structure due to the limitation in computing power. Full article

(This article belongs to the Special Issue Application of Artificial Intelligence and Deep Learning in Wireless Communications Systems)

Open AccessArticle

Yuccalechins A–C from the Yucca schidigera Roezl ex Ortgies Bark: Elucidation of the Relative and Absolute Configurations of Three New Spirobiflavonoids and Their Cholinesterase Inhibitory Activities

by

Łukasz Pecio ,

Mostafa Alilou ,

Ilkay Erdogan Orhan ,

Gokcen Eren ,

Fatma Sezer Senol Deniz ,

Hermann Stuppner and

Wiesław Oleszek

Molecules 2019, 24(22), 4162; https://doi.org/10.3390/molecules24224162 (registering DOI) - 16 Nov 2019

Abstract

The ethyl acetate fraction of the methanolic extract of Yucca schidigera Roezl ex Ortgies bark exhibited moderate acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity (IC₅₀ 47.44 and 47.40 µg mL⁻¹, respectively). Gel filtration on Sephadex LH-20 and further RP-C₁₈ [...] Read more.

The ethyl acetate fraction of the methanolic extract of Yucca schidigera Roezl ex Ortgies bark exhibited moderate acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity (IC₅₀ 47.44 and 47.40 µg mL⁻¹, respectively). Gel filtration on Sephadex LH-20 and further RP-C₁₈ preparative HPLC of EtOAc fraction afforded 15 known and 3 new compounds, stereoisomers of larixinol. The structures of the isolated spirobiflavonoids 15, 26, and 29 were elucidated using 1D and 2D NMR and MS spectroscopic techniques. The relative configuration of isolated compounds was assigned based on coupling constants and ROESY (rotating-frame Overhauser spectroscopy) correlations along with applying the DP4+ probability method in case of ambiguous chiral centers. Determination of absolute configuration was performed by comparing calculated electronic circular dichroism (ECD) spectra with experimental ones. Compounds 26 and 29, obtained in sufficient amounts, were evaluated for activities against AChE and BChE, and they showed a weak inhibition only towards AChE (IC₅₀ 294.18 µM for 26, and 655.18 µM for 29). Furthermore, molecular docking simulations were performed to investigate the possible binding modes of 26 and 29 with AChE. Full article

(This article belongs to the Special Issue NMR Spectroscopy in Natural Product Structure Elucidation)

Open AccessFeature PaperArticle

SwimBIT: A Novel Approach to Stroke Analysis During Swim Training Based on Attitude and Heading Reference System (AHRS)

by

Eduardo Ramos Félix ,

Hugo Plácido da Silva ,

Bjørn Harald Olstad ,

Jan Cabri and

Paulo Lobato Correia

Sports 2019, 7(11), 238; https://doi.org/10.3390/sports7110238 (registering DOI) - 16 Nov 2019

Abstract

In a world where technology is assuming a pervasive role, sports sciences are also increasingly exploiting the possibilities opened by advanced sensors and intelligent algorithms. This paper focuses on the development of a convenient, practical, and low-cost system, SwimBIT, which is intended to [...] Read more.

In a world where technology is assuming a pervasive role, sports sciences are also increasingly exploiting the possibilities opened by advanced sensors and intelligent algorithms. This paper focuses on the development of a convenient, practical, and low-cost system, SwimBIT, which is intended to help swimmers and coaches in performance evaluation, improvement, and injury reduction. Real-world data were collected from 13 triathletes (age 20.8 ± 3.5 years, height 173.7 ± 5.3 cm, and weight 63.5 ± 6.3 kg) with different skill levels in performing the four competitive styles of swimming in order to develop a representative database and allow assessment of the system’s performance in swimming conditions. The hardware collects a set of signals from swimmers based on an attitude and heading reference system (AHRS), and a machine learning workflow for data analysis is used to extract a selection of indicators that allows analysis of a swimmer's performance. Based on the AHRS data, three novel indicators are proposed: trunk elevation, body balance, and body rotation. Experimental evaluation has shown promising results, with a 100% accuracy in swim lap segmentation, a precision of 100% in the recognition of backstroke, and a precision of 89.60% in the three remaining swimming techniques (butterfly, breaststroke, and front crawl). The performance indicators proposed here provide valuable information for both swimmers and coaches in their quest for enhancing performance and preventing injuries. Full article

(This article belongs to the Special Issue Applied Sport Science for Elite Athletes)

Open AccessReview

Pyrido[2,3-d]pyrimidin-7(8H)-ones: Synthesis and Biomedical Applications

by

Guillem Jubete ,

Raimon Puig de la Bellacasa ,

Roger Estrada-Tejedor ,

Jordi Teixidó and

José I. Borrell

Molecules 2019, 24(22), 4161; https://doi.org/10.3390/molecules24224161 (registering DOI) - 16 Nov 2019

Abstract

Pyrido[2,3-d]pyrimidines (1) are a type of privileged heterocyclic scaffolds capable of providing ligands for several receptors in the body. Among such structures, our group and others have been particularly interested in pyrido[2,3-d]pyrimidine-7(8H)-ones (2) [...] Read more.

Pyrido[2,3-d]pyrimidines (1) are a type of privileged heterocyclic scaffolds capable of providing ligands for several receptors in the body. Among such structures, our group and others have been particularly interested in pyrido[2,3-d]pyrimidine-7(8H)-ones (2) due to the similitude with nitrogen bases present in DNA and RNA. Currently there are more than 20,000 structures 2 described which correspond to around 2900 references (half of them being patents). Furthermore, the number of references containing compounds of general structure 2 have increased almost exponentially in the last 10 years. The present review covers the synthetic methods used for the synthesis of pyrido[2,3-d]pyrimidine-7(8H)-ones (2), both starting from a preformed pyrimidine ring or a pyridine ring, and the biomedical applications of such compounds. Full article

(This article belongs to the collection Heterocyclic Compounds)

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Open AccessArticle

In Silico Molecular Studies of Antiophidic Properties of the Amazonian Tree Cordia nodosa Lam.

by

Carmen X. Luzuriaga-Quichimbo ,

José Blanco-Salas ,

Luz María Muñoz-Centeno ,

Rafael Peláez ,

Carlos E. Cerón-Martínez and

Trinidad Ruiz-Téllez

Molecules 2019, 24(22), 4160; https://doi.org/10.3390/molecules24224160 (registering DOI) - 16 Nov 2019

Abstract

We carried out surveys on the use of Cordia nodosa Lam. in the jungles of Bobonaza (Ecuador). We documented this knowledge to prevent its loss under the Framework of the Convention on Biological Diversity and the Nagoya Protocol. We conducted bibliographic research and [...] Read more.

We carried out surveys on the use of Cordia nodosa Lam. in the jungles of Bobonaza (Ecuador). We documented this knowledge to prevent its loss under the Framework of the Convention on Biological Diversity and the Nagoya Protocol. We conducted bibliographic research and identified quercetrin as a significant bioactive molecule. We studied its in silico biological activity. The selected methodology was virtual docking experiments with the proteins responsible for the venomous action of snakes. The molecular structures of quercetrin and 21 selected toxins underwent corresponding tests with SwissDock and Chimera software. The results point to support its antiophidic use. They show reasonable geometries and a binding free energy of −7 to −10.03 kcal/mol. The most favorable values were obtained for the venom of the Asian snake Naja atra (5Z2G, −10.03 kcal/mol). Good results were also obtained from the venom of the Latin American Bothrops pirajai (3CYL, –9.71 kcal/mol) and that of Ecuadorian Bothrops asper snakes (5TFV, –9.47 kcal/mol) and Bothrops atrox (5TS5, –9.49 kcal/mol). In the 5Z2G and 5TS5 L-amino acid oxidases, quercetrin binds in a pocket adjacent to the FAD cofactor, while in the myotoxic homologues of PLA2, 3CYL and 5TFV, it joins in the hydrophobic channel formed when oligomerizing, in the first one similar to α-tocopherol. This study presents a case demonstration of the potential of bioinformatic tools in the validation process of ethnobotanical phytopharmaceuticals and how in silico methods are becoming increasingly useful for sustainable drug discovery. Full article

(This article belongs to the Special Issue Combinatorial, Computational and High Throughput Screening for Bioactive/Lead Finding from Nature/Synthesis)

Open AccessReview

Nerve, Muscle, and Synaptogenesis

by

Lauren Eric Swenarchuk

Cells 2019, 8(11), 1448; https://doi.org/10.3390/cells8111448 (registering DOI) - 16 Nov 2019

Abstract

The vertebrate skeletal neuromuscular junction (NMJ) has long served as a model system for studying synapse structure, function, and development. Over the last several decades, a neuron-specific isoform of agrin, a heparan sulfate proteoglycan, has been identified as playing a central role in [...] Read more.

The vertebrate skeletal neuromuscular junction (NMJ) has long served as a model system for studying synapse structure, function, and development. Over the last several decades, a neuron-specific isoform of agrin, a heparan sulfate proteoglycan, has been identified as playing a central role in synapse formation at all vertebrate skeletal neuromuscular synapses. While agrin was initially postulated to be the inductive molecule that initiates synaptogenesis, this model has been modified in response to work showing that postsynaptic differentiation can develop in the absence of innervation, and that synapses can form in transgenic mice in which the agrin gene is ablated. In place of a unitary mechanism for neuromuscular synapse formation, studies in both mice and zebrafish have led to the proposal that two mechanisms mediate synaptogenesis, with some synapses being induced by nerve contact while others involve the incorporation of prepatterned postsynaptic structures. Moreover, the current model also proposes that agrin can serve two functions, to induce synaptogenesis and to stabilize new synapses, once these are formed. This review examines the evidence for these propositions, and concludes that it remains possible that a single molecular mechanism mediates synaptogenesis at all NMJs, and that agrin acts as a stabilizer, while its role as inducer is open to question. Moreover, if agrin does not act to initiate synaptogenesis, it follows that as yet uncharacterized molecular interactions are required to play this essential inductive role. Several alternatives to agrin for this function are suggested, including focal pericellular proteolysis and integrin signaling, but all require experimental validation. Full article

Open AccessArticle

An Enhanced Trust Mechanism with Consensus-Based False Information Filtering Algorithm against Bad-Mouthing Attacks and False-Praise Attacks in WSNs

by

Taisuk Suh and

Youngho Cho

Electronics 2019, 8(11), 1359; https://doi.org/10.3390/electronics8111359 (registering DOI) - 16 Nov 2019

Abstract

To defend against insider attacks in wireless sensor networks (WSNs), trust mechanisms (TMs) using the notion of trust in human society have been proposed and are still actively researched. In the WSN with a trust mechanism (TM), each sensor node evaluates the trustworthiness [...] Read more.

To defend against insider attacks in wireless sensor networks (WSNs), trust mechanisms (TMs) using the notion of trust in human society have been proposed and are still actively researched. In the WSN with a trust mechanism (TM), each sensor node evaluates the trustworthiness of its neighbor sensors based on their behaviors, for example packet forwarding, and collaborates only with trustworthy neighbors while removing untrustworthy neighbor from its neighbor list. The reputation system (RS) is an advanced type of trust mechanism that evaluates the trustworthiness of a node by additionally considering neighbor nodes’ observations or evaluations about it. However, intelligent inside attackers in WSNs can discover the security vulnerabilities of trust mechanisms by examining the operations of TM (or RS), because the software modules of the TM (or RS) are installed and operating in their local storage and memory, and thus, they can avoid detection by the trust mechanisms. Bad-mouthing attacks and false-praise attacks are well-known examples of such intelligent insider attacks. We observed that existing trust mechanisms do not have effective countermeasures to defend against such attacks. In this paper, we propose an enhanced trust mechanism with a consensus-based false information filtering algorithm (TM-CFIFA) that can effectively defend against bad-mouthing attacks and false-praise attacks. According to our experiment results, compared with an existing representative RS model, our TM-CFIFA shortened the detection time of a packet drop attacker, which is supported by a false-praise attacker by at least 83%, and also extended the lifetime of a victim sensor node that is under bad-mouthing attacks by at least 15.8%. Full article

(This article belongs to the Section Networks)

Open AccessReview

Metal Oxide Nanoparticles in Therapeutic Regulation of Macrophage Functions

by

Marina S. Dukhinova ,

Artur. Y. Prilepskii ,

Alexander A. Shtil and

Vladimir V. Vinogradov

Nanomaterials 2019, 9(11), 1631; https://doi.org/10.3390/nano9111631 (registering DOI) - 16 Nov 2019

Abstract

Macrophages are components of the innate immune system that control a plethora of biological processes. Macrophages can be activated towards pro-inflammatory (M1) or anti-inflammatory (M2) phenotypes depending on the cue; however, polarization may be altered in bacterial and viral infections, cancer, or autoimmune [...] Read more.

Macrophages are components of the innate immune system that control a plethora of biological processes. Macrophages can be activated towards pro-inflammatory (M1) or anti-inflammatory (M2) phenotypes depending on the cue; however, polarization may be altered in bacterial and viral infections, cancer, or autoimmune diseases. Metal (zinc, iron, titanium, copper, etc.) oxide nanoparticles are widely used in therapeutic applications as drugs, nanocarriers, and diagnostic tools. Macrophages can recognize and engulf nanoparticles, while the influence of macrophage-nanoparticle interaction on cell polarization remains unclear. In this review, we summarize the molecular mechanisms that drive macrophage activation phenotypes and functions upon interaction with nanoparticles in an inflammatory microenvironment. The manifold effects of metal oxide nanoparticles on macrophages depend on the type of metal and the route of synthesis. While largely considered as drug transporters, metal oxide nanoparticles nevertheless have an immunotherapeutic potential, as they can evoke pro- or anti-inflammatory effects on macrophages and become essential for macrophage profiling in cancer, wound healing, infections, and autoimmunity. Full article

(This article belongs to the Special Issue Immune Responses to Nanomaterials for Biomedical Applications)

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Open AccessArticle

A Molecular Electron Density Theory Study of the Synthesis of Spirobipyrazolines through the Domino Reaction of Nitrilimines with Allenoates

by

Luis R. Domingo ,

Fatemeh Ghodsi and

Mar Ríos-Gutiérrez

Molecules 2019, 24(22), 4159; https://doi.org/10.3390/molecules24224159 (registering DOI) - 16 Nov 2019

Abstract

The reaction of diphenyl nitrilimine (NI) with methyl 1-methyl-allenoate yielding a spirobipyrazoline has been studied within molecular electron density theory (MEDT) at the MPWB1K/6-311G(d) computational level in dichloromethane. This reaction is a domino process that comprises two consecutive 32CA reactions with the formation [...] Read more.

The reaction of diphenyl nitrilimine (NI) with methyl 1-methyl-allenoate yielding a spirobipyrazoline has been studied within molecular electron density theory (MEDT) at the MPWB1K/6-311G(d) computational level in dichloromethane. This reaction is a domino process that comprises two consecutive 32CA reactions with the formation of a pyrazoline intermediate. Analysis of the relative Gibbs free energies indicates that both 32CA reactions are highly regioselective, the first one being also completely chemoselective, in agreement with the experimental outcomes. The geometries of the TSs indicate that they are associated to asynchronous bond formation processes in which the shorter distance involves the C1 carbon of diphenyl NI. Despite the zwitterionic structure of diphenyl NI, the appearance of a pseudoradical structure at the beginning of the reaction path, with a very low energy cost, suggests that the 32CA reaction between diphenyl NI, a strong nucleophile, and the allenoate, a moderate electrophile, should be mechanistically considered on the borderline between pmr-type and cb-type 32CA reactions, somewhat closer to the latter. Full article

(This article belongs to the Special Issue The Molecular Electron Density Theory in Organic Chemistry)

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