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1.
Sensors (Basel) ; 22(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36298079

RESUMO

Wireless Sensors Networks are integrating human daily life at a fast rate. Applications cover a wide range of fields, including home security, agriculture, climate change, fire prevention, and so on and so forth. If WSN were initially flat networks, hierarchical, or cluster-based networks have been introduced in order to achieve a better performance in terms of energy efficiency, topology management, delay minimization, load balancing, routing techniques, etc. As cluster-based algorithms proved to be efficient in terms of energy balancing, security has been of less importance in the field. Data shared by nodes in a WSN can be very sensitive depending on the field of application. Therefore, it is important to ensure security at various levels of WSN. This paper proposes a formal modeling of the energy consumed to secure communications in a cluster-based WSN in general. The concept is implemented using the Proof of Authentication (POAh) paradigm of blockchain and applied to a Multi-hop Clustering Algorithm based on spectral classification. The studied metrics are residual energy in the network, the number of alive nodes, first and last dead node.


Assuntos
Blockchain , Redes de Comunicação de Computadores , Humanos , Tecnologia sem Fio , Análise por Conglomerados , Algoritmos
2.
Mol Biotechnol ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456961

RESUMO

The molecular electron density theory (MEDT) was employed to examine the [4 + 2] cycloaddition reaction between (E)-N-((dimethylamino)methylene)benzothioamide (1) and (S)-3-acryloyl-4-phenyloxazolidin-2-one (2) at the B3LYP/6-311++G(d,p) design level. Parr functions and energy studies clearly show that this reaction is regio- and stereoselective, in perfect agreement with experimental results. By evaluating the chemical mechanism in terms of bond evolution theory (BET) and electron localization function (ELF), which divulges a variety of variations in the electron density along the reaction path, a single-step mechanism with highly asynchronous transition states structures was revealed. Additionally, we conducted a docking study on compounds P1, P2, P3, and P4 in the SARS-CoV-2 main protease (6LU7) in comparison to Nirmatrelvir. Our findings provide confirmation that product P4 may serve as a potent antiviral drug.

3.
J Mol Graph Model ; 121: 108462, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37001439

RESUMO

In this paper, we design new forms of organic conjugated compounds-based quinoxaline derivatives. Specifically, we exploit density functional theory and time-dependent-density functional theory in order to study the structure, the optic, the electronic, the reorganization energy and the photovoltaic features of such new molecules. Particularly, all engineered compounds have a narrow band gap in the range of 0.696-0.721 eV, high oscillator frequency and good optical properties. Moreover, the PCBM is employed as an electron acceptor. Employing global reactivity descriptors, we demonstrate that the molecules can efficiently emit electrons into the PCBM and the electrons are attracted to PCBM from molecules. In addition, the results show an appropriate open circuit voltage in the range of 0.338-0.362 V. The proposed compounds exhibit excellent electron transport and charge conduction from the donor to the acceptor. These new molecules show potential properties to develop bulk heterojunction organic photovoltaic cells.


Assuntos
Elétrons , Quinoxalinas , Eletrônica , Teoria da Densidade Funcional , Transporte de Elétrons
4.
J Mol Graph Model ; 125: 108622, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37690428

RESUMO

Engineering electronic organic donor materials are one of the most critical steps in producing bulk-heterojunction solar cells (BHJ) with good photovoltaic properties. Compared to standard donor materials, electron donors derived from thiophene have made significant progress as they can be better suited for optoelectronics and are cheaper and more stable. Therefore, the use of new thiophene derivatives (M1-M4) as donor molecules in BHJs has been the subject of this extensive theoretical analysis. Density functional theory (DFT) and time-dependent DFT (TD-DFT) computations have been used to investigate the boundary molecular orbital (FMO) analysis, the density of states analysis, electron and hole reorganization energy, molecular electrostatic potential, global reactivity parameters, and photovoltaic properties. The effects of end-donor modifications on the photovoltaic and electronic characteristics of the new molecules (M1-M4) are investigated. According to the results, the molecules have good optical properties, a small band gap, a perfect open-circuit voltage, and a good alignment energy level between the designated donor molecules and the acceptor phenyl-C61-butyric acid methyl ester (PCBM). These results suggest that further research in this area could enhance the efficacy of organic solar cells.


Assuntos
Eletrônica , Elétrons , Teoria da Densidade Funcional , Ésteres , Tiofenos
5.
Pharmgenomics Pers Med ; 16: 901-909, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37810546

RESUMO

Introduction: Clopidogrel is an antiplatelet prodrug primarily prescribed to prevent or treat acute coronary syndrome (ACS) or acute ischemic stroke (IS), polymorphisms of genes encoding cytochrome P-450 (CYP) and P-glycoprotein transporter, could affect the efficiency of clopidogrel absorption and biotransformation, especially during the first critical hours following its administration. Methods: The present study was designed to investigate the potential association of clopidogrel responsiveness and 14 polymorphisms in the genes encoding the CYPs (CYP2C9, 2C19, 3A4, 3A5, 1A2, and 2B6), the ATP binding cassette subfamily B member 1 (ABCB1). Platelet aggregation activity was measured after 8h of 300mg clopidogrel administration for fifty-five ACS patients. Results: There was no significant association between polymorphism of the studied CYPs and clopidogrel responsiveness (P>0.05). The frequency of the ABCB1 3435 T allele in clopidogrel non-responders was higher (78.9%) compared to responders (52.8%), but this difference was not significant (P=0.057). Demographic characteristics, comorbidities, concomitant treatments were not associated with clopidogrel response. Discussion: There was no effect of the studied genetic variations and demographic factors on the platelet activity of clopidogrel in Moroccan ACS patients.

6.
Heliyon ; 8(9): e10673, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36164527

RESUMO

Background: Soft tissue sarcomas (STS) are a heterogeneous group of tumors. For adequate therapeutic management, an accurate diagnosis is necessary. In Morocco, the diagnosis is essentially based on the morphological and immunohistochemical study. Compared to other techniques, fluorescence in situ hybridization (FISH) is easier to develop and less expensive. This study aims to assess the feasibility and utility of implementing FISH technique to improve diagnostic accuracy and establish a good classification. Material and methods: This is a retrospective cohort study. 211 cases of mesenchymal tumors were included. Hematoxylin Eosin Safran (HES) staining was performed in all cases followed by immunohistochemistry (IHC). FISH was performed in all cases with suspected STS. The probes used were EWSR1, MDM2 and SS18. The performance of FISH and histopathological test were evaluated by the ROC curve method (receiver operating characteristic). We evaluated the concordance between FISH and real time PCR by Cohen test. Results: The real-time PCR technique showed good agreement with the FISH test by a Kappa coefficient of 60% (p = 0.035). FISH was able to confirm that it is more accurate (Youden's Index = 91%) than histological/immunohistochemical analysis (Youden's Index = 51%), as well as the positive predictive value was higher (100%) with an ROC curve finding a larger area under the curve of 0.953 (95% CI: 0.918-0.988), p = 0.000 which supports that FISH shows high performance to present an accurate final diagnosis. Conclusion: This is the first and the largest Moroccan series for the molecular diagnosis of STS by FISH. Our study shows that paraffin FISH is a sensitive and specific ancillary tool in the diagnosis of STS when used in the appropriate clinicopathological context.

7.
J Mol Model ; 27(7): 197, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34115227

RESUMO

In the current work, the chemical reactivity of some trivalent phosphorus derivatives R2PR' towards polyhaloalkanes CCl3POR ' '2 was studied by the quantum method DFT/B3LYP/6-311G(d,p). The introduction of substituents for the trivalent phosphorus derivative and polyhaloalkane allowed us to have more information on these reactions. On the one hand, the calculation of reactivity indices derived from the DFT/B3LYP/6-311G(d,p) method and the gapLUMO - HOMO show that trivalent organophosphorus derivatives behave as nucleophiles, while polyhaloalkanes act as electrophiles. On the other hand, the calculation of the activation barrier and the determination of the free enthalpy variation prove that the kinetic and thermodynamic products of these reactions result from the nucleophilic attack of the phosphorus atom on the chlorine halogen. All these theoretical predictions are in very good agreement with the experimental results.

8.
J Mol Model ; 27(4): 103, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33666775

RESUMO

Motivated by the use of chitosan (Ch), and cellulose acetate (AC) as organic matrices in several therapeutic drugs, a theoretical study has been elaborated through the density functional theory method (DFT) to investigate the interaction mechanism between two essential ions for the human body Ca2+, K+ and two organic matrices chitosan (Ch), and cellulose acetate (AC). Many physical and chemical aspects have been carried out after the achievement of structural optimization. This involves structural parameters, molecular electrostatic potential (MEPs), interaction energy, reactivity indexes, frontier molecular orbitals (FMOs), quantum theory atoms in molecules (QTAIM) analysis, and non-covalent interaction (NCI) analysis. The results of FMOs, MEPs, and reactivity index studies have revealed that the site of interaction can be predicted. The calculation of electron interaction energies shows that those ions interact with the matrix of AC and Ch. Concretely, the Ca2+ ion interacted efficiently with the AC matrix. The structural analysis results show that the interaction of Ch and ions appear spontaneously (ΔG < 0) while the interaction of AC and ions (ΔG >0) requires more energy to occur. Finally, the QTAIM analysis data indicates that the interactions of AC-ions and Ch-ions are non-covalent presenting an electrostatic character.


Assuntos
Cálcio/química , Celulose/análogos & derivados , Quitosana/química , Teoria da Densidade Funcional , Potássio/química , Cátions , Celulose/química , Química Computacional , Modelos Moleculares
9.
J Mol Graph Model ; 102: 107760, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33130389

RESUMO

In the present paper, an investigation about the [3 + 2]cycloaddition (32 C A) reactions of benzonitrile oxide with 1-trifluoromethyl-4-vinyl-benzene, and with 1-methyl-4-vinyl-benzene, using the Molecular Electron Density Theory (MEDT) through DFT/B3LYP/6-311++G (d,p), is performed. A deep mechanistic study beside an accurate electronic description of different stationary points along the IRC paths of the two 32 C A reactions have performed by examining the two competitive regioisomericortho/metareaction pathways, and providing the mechanism associated with them. The presence of the CF3 group reduces the activation energy, which makes it possible to increase the experimental yield of the reaction in good agreement with the experimental results. Addition of solvent (THF) does not affected the regioselectivity of the studied reactions. Evaluation of the ELF of selected structures of the IRC related with the formation of C-O and C-C single bonds designates that these 32 C A reactions take place through a one-step, two-stage mechanism.


Assuntos
Benzeno , Elétrons , Reação de Cicloadição , Modelos Moleculares , Solventes
10.
J Mol Model ; 27(11): 331, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34713354

RESUMO

The adsorption of azelaic acid dihydrazide as an environmentally friendly mild steel corrosion inhibitor on the iron surface was modeled in this study. We used density functional theory (DFT) calculations and Monte Carlo (MC) and molecular dynamics (MD) simulations to illustrate the interactions engaged. The interaction of the azelaic acid derivatives with iron metal (Fe) was examined by DFT as a typical example of a corrosion prevention mechanism after the optimized molecular structures of these molecules were investigated. Structures, binding energies, Fikui's charge indicator, electron transfer, and chemical potential are all discussed. The presence of significant binding between the inhibitor and Fe metal is supported by analysis of the resultant complex. Then, in an acidic solution comprising 491 H2O, nine chlorine ion Cl-, and nine hydronium ion H3O+, molecular dynamics and Monte Carlo (MC) simulation were used to model the adsorption of azelaic acid dihydrazide on the iron Fe (110) surface. In addition, radial distribution function (RDF) and interaction energy (Ei) were evaluated in this work to further our understanding of interactions between azelaic acid dihydrazide and iron surfaces. Furthermore, we discovered that our inhibitors have an excellent ability to slow down the movement of corrosive particles in law temperature and thus to inhibit the metallic substrate against corrosive electrolyte, based on the temperature impact investigation. The result of density functional theory and Monte Carlo and molecular dynamics descriptors obtained were in good agreement with the experimental result.

12.
RSC Adv ; 9(49): 28500-28509, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-35529642

RESUMO

The epoxidation reaction of R-carvone 8 with peracetic acid 9 has been studied within the molecular electron density theory at the B3LYP/6-311(d,p) computational level. The chemo- and stereoisomeric reaction paths involving the two C-C double bonds of R-carvone 8 have been studied. DFT calculations account for the high chemoselectivity involving the C-C double bond of the isopropenyl group and the low diastereoselectivity, in complete agreement with the experimental outcomes. The Baeyer-Villiger reaction involving the carbonyl group of R-carvone 8 has also been analysed. A bonding evolution theory analysis of the epoxidation reaction shows the complexity of the bonding changes taking place along this reaction. Formation of the oxirane ring takes place asynchronously at the end of the reaction by attack of anionic oxygen on the two carbons of the isopropenyl C-C double bond.

13.
Pan Afr Med J ; 27: 133, 2017.
Artigo em Francês | MEDLINE | ID: mdl-28904663

RESUMO

Fractures of the upper extremity of the femur are serious because of their morbidity and social and/or economic consequences. They have been the subject of several studies of world literature concerning their hospital treatment, evolution and prevention. The increase in the incidence of this pathology seems unavoidable due to population ageing and to the lengthening life expectancy; it is posing a real long-term public health problem whose importance will be further increased by the need to control health care costs. The results of this study show that the average age of onset of fracture of the proximal extremity of the femur is 68,13 ± 16.9 years, with a male predominance and a sex ratio of 1.14. In our study pertrochanterian fractures represented 69.4% of cases. Direct medical costs of the hospital treatment of fractures of the upper extremity of the femur at the Hassan II University Hospital were £387 714,38 in 222 cases, with an average cost of £1757,4 , including costs for patient's stay in hospital, which represented the majority of expenses ( 77% of total costs). It is desirable to raise staff awareness of the costs of consumables in order to reduce treatment costs and to adopt cost-oriented behaviour. Length of stay should be limited to the maximum extent because it only allows to reduce staff and accommodation costs.


Assuntos
Fraturas do Fêmur/terapia , Custos de Cuidados de Saúde/estatística & dados numéricos , Custos Hospitalares/estatística & dados numéricos , Hospitalização/economia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas do Fêmur/economia , Humanos , Incidência , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Distribuição por Sexo , Adulto Jovem
14.
Pan Afr Med J ; 24: 53, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27642394

RESUMO

Recurrent respiratory tract infections are one of the most frequent reasons for pediatric visits and hospitalization. Causes of this pathology are multiple ranging from congenital to acquired and local to general. Immune deficiencies are considered as underlying conditions predisposing to this pathology. Our work is about to determine when and how to explore the immune system when facing recurrent respiratory infections. This was based on the records of 53 children hospitalized at the pediatrics unit of Hassan II University Hospital, Fez Morocco. Thirty boys and 23 girls with age ranging from 5 months to 12 years with an average age of 2 years were involved in this study. Bronchial foreign body was the main etiology in children of 3 to 6 year old. Gastro-esophageal reflux, which in some cases is a consequence of chronic cough, as well as asthma were most frequent in infants (17 and 15% respectively). Immune deficiency was described in 7.5% of patients and the only death we deplored in our series belongs to this group. Recurrent respiratory tract infections have multiple causes. In our series they are dominated by foreign body inhalation and gastroesophageal reflux, which in some cases is a consequence of a chronic cough. Immune deficiency is not frequent but could influence the prognosis. Therefore immune explorations should be well codified.


Assuntos
Corpos Estranhos/complicações , Refluxo Gastroesofágico/epidemiologia , Doenças do Sistema Imunitário/epidemiologia , Infecções Respiratórias/epidemiologia , Asma/epidemiologia , Criança , Pré-Escolar , Doença Crônica , Tosse/epidemiologia , Feminino , Hospitalização , Hospitais Universitários , Humanos , Doenças do Sistema Imunitário/complicações , Lactente , Masculino , Marrocos , Recidiva , Infecções Respiratórias/etiologia , Infecções Respiratórias/imunologia , Estudos Retrospectivos
15.
Exp Biol Med (Maywood) ; 230(11): 865-71, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16339752

RESUMO

The Docile strain of lymphocytic choriomeningitis virus (LCMV) induces anemia in a number of inbred strains of mice, including C3HeB/FeJ and CBA/Ht animals. A difference in the kinetics of anemia and in compensatory reticulocytosis suggested that impaired erythropoiesis was the major pathogenic mechanism involved in CBA/Ht mice, but not in C3HeB/FeJ mice. In both mouse strains an antierythrocyte autoantibody production that depended on the presence of functional CD4+ T lymphocytes was observed. Although depletion of T helper lymphocytes prevented anemia in C3HeB/FeJ mice, this treatment largely failed to inhibit the development of the disease in CBA/Ht animals. This observation indicated that the antierythrocyte autoimmune response induced by the infection was at least partly responsible for the anemia of C3HeB/FeJ mice, but not of CBA/Ht mice. Erythrophagocytosis was enhanced in both mouse strains after LCMV infection, but did not appear to be a major cause of anemia. These data clearly indicate that similar disease profiles induced by the same virus in two different host strains can be the result of distinctly different mechanisms.


Assuntos
Anemia Hemolítica Autoimune/imunologia , Infecções por Arenaviridae/imunologia , Hematopoese/imunologia , Vírus da Coriomeningite Linfocítica , Anemia Hemolítica Autoimune/etiologia , Anemia Hemolítica Autoimune/patologia , Animais , Formação de Anticorpos/imunologia , Infecções por Arenaviridae/complicações , Infecções por Arenaviridae/patologia , Autoanticorpos/imunologia , Autofagia/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Eritrócitos/imunologia , Depleção Linfocítica , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Camundongos Endogâmicos , Reticulocitose/imunologia , Especificidade da Espécie
16.
Autoimmunity ; 37(6-7): 515-20, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15621579

RESUMO

Autoimmune Graves' disease (GD), which is characterized by hyperthyroidism, is mediated by autoantibodies to the thyrotropin receptor (TSHR). Yersinia enterocolitica (Y.e.) has been shown to produce a lipoprotein (LP) that can cross-react with the TSHR and thus can act as a potential trigger of thyroid autoimmunity. In this study, to further characterize LP, we cloned the LP gene from Y. enterocolitica and expressed a recombinant LP. This recombinant LP was mitogenic for C3H/HeJ (LPS hyporesponsive) B cells and induced production and secretion of significant levels of IL-6 from splenocytes. A mouse antibody generated against the recombinant LP cross-reacted with TSHR as shown by western blot analysis. FACS analysis of splenocytes from mice immunized with LP revealed that LP could induce increased expression of B7.1 and B7.2. The immunomodulatory effects of LP including up-regulation of B7.1 and B7.2 coupled with its ability to induce antibodies that can cross-react with the TSHR showed several potential mechanisms by which it can cause breakdown of self-tolerance to TSHR.


Assuntos
Autoimunidade/imunologia , Lipoproteínas/genética , Receptores da Tireotropina/imunologia , Yersinia enterocolitica/genética , Animais , Antígenos CD/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Antígeno B7-2 , Interleucina-6/metabolismo , Lipoproteínas/metabolismo , Lipoproteínas/farmacologia , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos CBA , Regulação para Cima , Yersinia enterocolitica/metabolismo
17.
Pan Afr Med J ; 19: 325, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25918565

RESUMO

The combination of the acromion Open fracture to a section of the supraspinatus tendon is an exceptional situation. The author reports the case of a young patient with a wound of the posterolateral side of the right shoulder. Screwing was done for the fracture of the acromion after supraspinatus tendon suture with good clinical and radiological outcome after an appropriate rehabilitation.


Assuntos
Acrômio/patologia , Fraturas Expostas/patologia , Articulação do Ombro/patologia , Traumatismos dos Tendões/patologia , Acrômio/cirurgia , Fraturas Expostas/cirurgia , Humanos , Masculino , Ruptura/patologia , Ruptura/cirurgia , Técnicas de Sutura , Traumatismos dos Tendões/cirurgia , Adulto Jovem
19.
Pan Afr Med J ; 11: 32, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22514766

RESUMO

Soft tissue metastases from pancreatic adenocarcinoma are rare lesions and can be the source of diagnostic confusion both clinically and pathologically. To our knowledge, one patient has been reported on with soft tissue lesions that ultimately disclose a pancreatic adenocarcinoma. We report here on a patient who presented with a metastatic soft tissue lesion in the trochanter, and the buttocks, as the initial manifestation of pancreatic adenocarcinoma. Soft tissue metastasis from pancreatic carcinoma is a rare finding. Clinicians should be aware that metastatic soft tissue lesions could be the initial presenting sign for pancreatic cancer. Also, the immunohistochemical staining for CK 7 and 19 may be helpful for the diagnosis of metastatic pancreatic adenocarcinoma.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Neoplasias de Tecidos Moles/diagnóstico , Neoplasias de Tecidos Moles/secundário , Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Nádegas , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Coxa da Perna , Gencitabina
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