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1.
Microb Pathog ; 193: 106741, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38871198

RESUMO

The rise of antibiotic resistance poses a significant threat to public health worldwide, leading researchers to explore novel solutions to combat this growing problem. Nanotechnology, which involves manipulating materials at the nanoscale, has emerged as a promising avenue for developing novel strategies to combat antibiotic resistance. This cutting-edge technology has gained momentum in the medical field by offering a new approach to combating infectious diseases. Nanomaterial-based therapies hold significant potential in treating difficult bacterial infections by circumventing established drug resistance mechanisms. Moreover, their small size and unique physical properties enable them to effectively target biofilms, which are commonly linked to resistance development. By leveraging these advantages, nanomaterials present a viable solution to enhance the effectiveness of existing antibiotics or even create entirely new antibacterial mechanisms. This review article explores the current landscape of antibiotic resistance and underscores the pivotal role that nanotechnology plays in augmenting the efficacy of traditional antibiotics. Furthermore, it addresses the challenges and opportunities within the realm of nanotechnology for combating antibiotic resistance, while also outlining future research directions in this critical area. Overall, this comprehensive review articulates the potential of nanotechnology in addressing the urgent public health concern of antibiotic resistance, highlighting its transformative capabilities in healthcare.


Assuntos
Antibacterianos , Infecções Bacterianas , Biofilmes , Nanotecnologia , Nanotecnologia/métodos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Humanos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Biofilmes/efeitos dos fármacos , Nanoestruturas , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana , Resistência Microbiana a Medicamentos
2.
Cell Biol Toxicol ; 40(1): 77, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283408

RESUMO

Gastrointestinal (GI) cancers are common cancers that are responsible for a large portion of global cancer fatalities. Due to this, there is a pressing need for innovative strategies to identify and treat GI cancers. MicroRNAs (miRNAs) are short ncRNAs that can be considered either cancer-causing or tumor-inhibiting molecules. MicroRNA-155, also known as miR-155, is a vital regulator in various cancer types. This miRNA has a carcinogenic role in a variety of gastrointestinal cancers, including pancreatic, colon, and gastric cancers. Since the abnormal production of miR-155 has been detected in various malignancies and has a correlation with increased mortality, it is a promising target for future therapeutic approaches. Moreover, exosomal miR-155 associated with tumors have significant functions in communicating between cells and establishing the microenvironment for cancer in GI cancers. Various types of genetic material, such as specifically miR-155 as well as proteins found in cancer-related exosomes, have the ability to be transmitted to other cells and have a function in the advancement of tumor. Therefore, it is critical to conduct a review that outlines the diverse functions of miR-155 in gastrointestinal malignancies. As a result, we present a current overview of the role of miR-155 in gastrointestinal cancers. Our research highlighted the role of miR-155 in GI cancers and covered critical issues in GI cancer such as pharmacologic inhibitors of miRNA-155, miRNA-155-assosiated circular RNAs, immune-related cells contain miRNA-155. Importantly, we discussed miRNA-155 in GI cancer resistance to chemotherapy, diagnosis and clinical trials. Furthermore, the function of miR-155 enclosed in exosomes that are released by cancer cells or tumor-associated macrophages is also covered.


Assuntos
Exossomos , Neoplasias Gastrointestinais , MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Exossomos/metabolismo , Exossomos/genética , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/metabolismo , Neoplasias Gastrointestinais/patologia , Microambiente Tumoral/genética , Animais , Regulação Neoplásica da Expressão Gênica
3.
J Chem Phys ; 160(13)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38557837

RESUMO

DL_POLY Quantum 2.0, a vastly expanded software based on DL_POLY Classic 1.10, is a highly parallelized computational suite written in FORTRAN77 with a modular structure for incorporating nuclear quantum effects into large-scale/long-time molecular dynamics simulations. This is achieved by presenting users with a wide selection of state-of-the-art dynamics methods that utilize the isomorphism between a classical ring polymer and Feynman's path integral formalism of quantum mechanics. The flexible and user-friendly input/output handling system allows the control of methodology, integration schemes, and thermostatting. DL_POLY Quantum is equipped with a module specifically assigned for calculating correlation functions and printing out the values for sought-after quantities, such as dipole moments and center-of-mass velocities, with packaged tools for calculating infrared absorption spectra and diffusion coefficients.

4.
Cancer Cell Int ; 23(1): 335, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129839

RESUMO

Green tea, a popular and healthy nonalcoholic drink consumed globally, is abundant in natural polyphenols. One of these polyphenols is epigallocatechin-3-gallate (EGCG), which offers a range of health benefits, such as metabolic regulation, antioxidant properties, anti-inflammatory effects, and potential anticancer properties. Clinical research has shown that EGCG can inhibit cancers in the male and female reproductive systems, including ovarian, cervical, endometrial, breast, testicular, and prostate cancers. Further research on cervical cancer has revealed the crucial role of epigenetic mechanisms in the initiation and progression of this type of cancer. These include changes to the DNA, histones, and non-coding RNAs, such as microRNAs. These changes are reversible and can occur even before genetic mutations, making them a potential target for intervention therapies. One promising approach to cancer prevention and treatment is the use of specific agents (known as epi-drugs) that target the cancer epigenome or epigenetic dysregulation. Phytochemicals, a group of diverse molecules, have shown potential in modulating cancer processes through their interaction with the epigenetic machinery. Among these, green tea and its main polyphenol EGCG have been extensively studied. This review highlights the therapeutic effects of EGCG and its nanoformulations on cervical cancer. It also discusses the epigenetic events involved in cervical cancer, such as DNA methylation and microRNA dysregulation, which may be affected by EGCG.

5.
J Chem Inf Model ; 63(22): 7097-7106, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37811792

RESUMO

Most of the chemistry in nanoporous materials with small pore sizes and windows takes place on the outer surface, which is in direct contact with the substrate/solvent, rather than within the pores and channels. Here, we report the results of our comprehensive atomistic molecular dynamics (MD) simulations to decipher the interaction of water with a realistic finite ∼5.1 nm nanoparticle (NP) model of ZIF-8, with edges containing undercoordinated Zn metal sites, vs a conventionally employed pristine crystalline bulk (CB) model. The hydrophobic interior surface of the CB model imparts significant dynamical behavior on water molecules with (i) increasing diffusivity from the surface toward the center of the pores and (ii) confined water, at low concentration, showing similar diffusivity to that of the bulk water. On the other hand, water molecules adsorbed on the surface of the NP model exhibit a range of characteristics, including "coordinated", "confined", and "bulk-like" behavior. Some of the water molecules form coordinative bonds with the undercoordinated Zn metal centers and act as nucleation sites for the water droplets to form, facilitating diffusion into the pores. However, diffusion of water molecules is limited to the areas near the surface and not all the way to the core of the NP model. Our atomistic MD simulations provide insights into the stability of ZIFs in aqueous solutions despite hydrolysis of their outer surface. Such insights are helpful in designing more robust nanoporous materials for applications in humid environments.


Assuntos
Água , Zeolitas , Água/química , Zeolitas/química , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular , Metais
6.
Phys Chem Chem Phys ; 24(41): 25673-25674, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36250515

RESUMO

Correction for 'Gauging van der Waals interactions in aqueous solutions of 2D MOFs: when water likes organic linkers more than open-metal sites' by Mohammad R. Momeni et al., Phys. Chem. Chem. Phys., 2021, 23, 3135-3143, https://doi.org/10.1039/D0CP05923D.

7.
Environ Res ; 207: 112157, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34619122

RESUMO

This paper investigates the synthesis, antibacterial, and photocatalytic properties of silver ion-exchanged natural zeolite/TiO2 photocatalyst nanocomposite. Zeolite is known to have a porous surface structure, making it an ideal substrate and framework in different nanocomposites. Moreover, natural zeolite has a superior thermal and chemical stability, with hardly any reactivity with chemicals. Finding an effective and low-cost method to remove both antibiotics and bacteria from water resources has become a vital global issue due to the worldwide excessive use of chemicals and antibiotics. This research aims to propose a facile method to synthesize Ag-ion-exchanged zeolite/TiO2 catalyst for anti-bacterial purposes and photocatalytic removal of atibiotics from wastewaters. TiO2 particles were deposited on the surface of natural zeolite. Ag ion exchanging was performed via a liquid ion-exchange method using 0.1 M AgNO3 solution. X-ray diffractometry (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared spectroscopy (FTIR) were used to evaluate the structure of synthesized powders. Antibacterial activities of samples were assessed, using Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 by disc diffusion method. It was shown that Ag-containing nanocomposite samples have an improved antibacterial performance in both cases. Results showed that the synthesized catalyst has promising potentials in wastewater treatment.


Assuntos
Nanocompostos , Zeolitas , Antibacterianos/química , Antibacterianos/farmacologia , Nanocompostos/química , Titânio/química , Zeolitas/química
8.
J Chem Phys ; 156(4): 044109, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35105086

RESUMO

Optimizing energy and charge transfer is key in design and implementation of efficient layered conductive metal-organic frameworks (MOFs) for practical applications. In this work, for the first time, we investigate the role of both long-range excitonic and short-range charge transfer coupling as well as their dependency on reorganization energy on through-space charge transfer in layered MOFs. A π-stacked model system is built based on the archetypal Ni3(HITP)2, HITP = 2,3,6,7,10,11-hexaiminotriphenylene, layered MOF, and a Frenkel/charge transfer Holstein Hamiltonian is developed that takes into account both electronic coupling and intramolecular vibrations. The dependency of the long- and short-range couplings of secondary building units (SBUs) on the stacking geometry is evaluated, which predicts that photophysical properties of layered MOFs critically depend on the degree of ordering between layers. We show that the impact of the two coupling sources in these materials can be discerned or enhanced by the displacement of the SBUs along the long or short molecular axes. The effects of vibronic spectral signatures are examined in both perturbative and resonance regimes. Although, to the best of our knowledge, displacement engineering in layered MOFs currently remains beyond reach, the findings reported here offer new details on the photophysical structure-property relationships in layered MOFs and provide suggestions on how to combine elements of molecular design and engineering to achieve desirable properties and functions for nano- and mesoscale optoelectronic applications.

9.
Inflammopharmacology ; 30(5): 1645-1657, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35834150

RESUMO

BACKGROUND: It is known that severe acute respiratory coronavirus 2 (SARS-CoV-2) is the viral strain responsible for the recent coronavirus disease 2019 (COVID-19) pandemic. Current documents have demonstrated that the virus causes a PGE2 storm in a substantial proportion of patients via upregulating cyclooxygenase-2 (COX-2) and downregulating prostaglandin E2 (PGE2)-degrading enzymes within the host cell. AIM: Herein, we aimed to study how short-term treatment with celecoxib (Celebrex), a selective COX-2 inhibitor, affects demographic features, early symptoms, O2 saturation, and hematological indices of cases with COVID-19. METHODS: A total of 67 confirmed COVID-19 cases with a mild or moderate disease, who had been referred to an institutional hospital in south-eastern Iran from October 2020 to September 2021, were enrolled. Demographic characteristics, symptoms, and hematological indices of the patients were recorded within different time periods. One-way ANOVA or Kruskal-Wallis tests were used to determine differences between data sets based on normal data distribution. RESULTS: O2 saturation was statistically different between the control group and patients receiving celecoxib (p = 0.039). There was no marked difference between the groups in terms of the symptoms they experienced (p > 0.05). On the first days following Celebrex therapy, analysis of complete blood counts showed that white blood cell (WBC) counts were markedly lower in patients treated with a high dose of celecoxib (0.4 g/day) than in controls (p = 0.026). However, mean lymphocyte levels in patients receiving a high dose of celecoxib (0.4 g/day) were markedly higher than in patients receiving celecoxib with half of the dose (0.2 g/day) for one week or the untreated subjects (p = 0.004). Changes in platelet count also followed the WBC alteration pattern. CONCLUSION: Celecoxib is a relatively safe, inexpensive, and widely available drug with non-steroidal anti-inflammatory properties. The therapeutic efficacy of celecoxib depends on the administrated dose. Celecoxib might improve disease-free survival in patients with COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , Inibidores de Ciclo-Oxigenase 2 , Anti-Inflamatórios não Esteroides/efeitos adversos , Celecoxib/uso terapêutico , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Dinoprostona , Humanos , Pirazóis/efeitos adversos , SARS-CoV-2 , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico
10.
Phys Chem Chem Phys ; 23(4): 3135-3143, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33491712

RESUMO

Molecular dynamics simulations combined with periodic electronic structure calculations are performed to decipher structural, thermodynamical and dynamical properties of the interfaced vs. confined water adsorbed in hexagonal 1D channels of the 2D layered electrically conductive Cu3(HHTP)2 and Cu3(HTTP)2 metal-organic frameworks (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene and HTTP = 2,3,6,7,10,11-hexathiotriphenylene). Comparing water adsorption in bulk vs. slab models of the studied 2D MOFs shows that water is preferentially adsorbed on the framework walls via forming hydrogen bonds to the organic linkers rather than by coordinating to the coordinatively unsaturated open-Cu2+ sites. Theory predicts that in Cu3(HTTP)2 the van der Waals interactions are stronger which helps the MOF maintain its layered morphology with allowing very little water molecules to diffuse into the interlayer space. Data presented in this work are general and helpful in implementing new strategies for preserving the integrity as well as electrical conductivity of porous materials in aqueous solutions.

11.
Radiol Med ; 125(1): 68-74, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31531809

RESUMO

OBJECTIVE: In this study, we prospectively investigated the diagnostic capability of diffusion-weighted magnetic resonance imaging (DWI) in assessing vertebral marrow changes in postmenopausal women with osteoporosis. MATERIALS AND METHODS: Sixty postmenopausal women (mean age 60.2 ± 6.11 years) underwent both dual-energy X-ray absorptiometry (DEXA) of the spine and MRI. Results were acquired from each patient's L2 to L4, for a total of 180 lumbar vertebrae. Based on bone mineral density (BMD) measurements obtained from DEXA, the vertebrae were divided into three groups as follows: normal (n = 52), osteopenic (n = 92), and osteoporotic (n = 36). DWI of the vertebral body was performed to assess the apparent diffusion coefficient (ADC). The ADC outcomes were compared among the three groups and correlated with BMD. RESULTS: ADC values (× 10-6 mm2/s) were significantly lower in the osteoporotic group (135.67 ± 44.10) in comparison to the normal group (561.85 ± 190.37) (P = 0.0001). The results showed a positive correlation between ADC and BMD values (r = 0.748, P = 0.0001). In receiver operating characteristic (ROC) analysis, the area under the curve for DWI was 0.912 (P = 0.001). A cut-off value of 400 mm2/s for the diagnosis of osteoporosis; had sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 90.90%, 83.34%, 88.89%, 93.75%, and 76.93%, respectively. CONCLUSION: ADC values correlated positively with BMD in women. DWI can allow quantitative evaluation of bone marrow changes and osteoporosis in postmenopausal women.


Assuntos
Densidade Óssea , Medula Óssea/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Vértebras Lombares/diagnóstico por imagem , Osteoporose Pós-Menopausa/diagnóstico por imagem , Pós-Menopausa , Absorciometria de Fóton , Área Sob a Curva , Doenças Ósseas Metabólicas/diagnóstico por imagem , Medula Óssea/fisiologia , Feminino , Humanos , Vértebras Lombares/fisiologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/classificação , Osteoporose Pós-Menopausa/fisiopatologia , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Estatísticas não Paramétricas
12.
J Cell Physiol ; 234(4): 3307-3320, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30362507

RESUMO

Melanoma is known as an aggressive tumor which shows an increasing incidence and poor prognosis in the metastatic phase. Hence, it seems that diagnosis and effective management (including early diagnosis, choosing of the effective therapeutic platform, caring, and training of patients for early detection) are major aspects of melanoma therapy. Early detection of melanoma is a key point for melanoma therapy. There are various diagnosis options such as assessing of biopsy, imaging techniques, and biomarkers (i.e., several proteins, polymorphism, and liquid biopsy). Among the various biomarkers, assessing circulating tumor cells, cell-free DNAs, cell-free RNAs, and microRNAs (miRNAs) have emerged as powerful diagnosis tools for melanoma patients. Deregulations of these molecules are associated with melanoma pathogenesis. After detection of melanoma, choosing of effective therapeutic regimen is a key step for recovery of melanoma patients. Several studies indicated that various therapeutic approaches including surgery, immunotherapy, systematic therapy, radiation therapy and antibodies therapy could be used as potential therapeutic candidates for melanoma therapy. Caring for melanoma patients is one of the important components of melanoma therapy. Caring and training for melanoma patients could contribute to better monitoring of patients in response to various therapeutic options. Here, we summarized various diagnosis approaches such as assessing biopsy, imaging techniques, and utilization of various biomarkers (i.e., proteins, CTCs, cfDNAs, and miRNAs) as a diagnostic biomarker for detection and monitoring patients with melanoma. Moreover, we highlighted various therapeutic options and caring aspects in patients with melanoma.


Assuntos
Melanoma/terapia , Neoplasias Cutâneas/terapia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Melanoma/genética , Melanoma/metabolismo , Melanoma/secundário , MicroRNAs/genética , MicroRNAs/metabolismo , Valor Preditivo dos Testes , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Resultado do Tratamento
13.
Blood Cells Mol Dis ; 74: 1-4, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30293687

RESUMO

OBJECTIVE: Portal vein thrombosis (PVT) has been described as a rare complication after splenectomy. PVT associated risk factors after splenectomy in hematological disorders are poorly recognized. The aim of this study was to assess the prevalence and risk factors of PVT incidence in splenectomized patients. METHODS: One hundred twelve splenectomized patients with various hematologic diseases between 2008 and 2018 were enrolled in this study. Diagnosis was confirmed by Doppler ultrasonography (DUSG) and risk factors for PVT were sought based on the comparison of clinical and laboratory features between patients without and with PVT. RESULT: PVT was diagnosed in 4 (3.57%) patients in spite of receiving antiplatelet therapy. Patients with PVT were ß-thalassemia major (n = 2) and ß-thalassemia intermedia (n = 2). ß-thalassemia patients had a 3.5 times higher odds for PVT (95% CI: 2.41-5.33). No significant differences between patients with and without PVT in terms of age, gender and laboratory features were found. CONCLUSION: According to our data, ß-thalassemia, especially intermediate form, may be a risk factor for PVT and it can occur in spite of receiving antiplatelet therapy. Given that ß-thalassemia patients are at risk, early PVT detection may be useful for reduction of fatal PVT complication in splenectomized patients.


Assuntos
Doenças Hematológicas/complicações , Veia Porta/patologia , Esplenectomia/efeitos adversos , Trombose Venosa/etiologia , Estudos de Casos e Controles , Humanos , Incidência , Estudos Retrospectivos , Fatores de Risco , Trombose Venosa/diagnóstico , Talassemia beta/complicações
14.
J Clin Ultrasound ; 47(7): 423-425, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30801724

RESUMO

Aneurysm of the inferior vena cava is a rare anomaly with a very few reported cases worldwide. We report the case of a 26-years-old man with acute severe abdominal pain and hypovolemic shock following an episode of syncope. Ultrasonography showed a fusiform aneurysmal dilation of the infra-hepatic inferior vena cava (IVC), with a large saccular portion at its posterolateral wall and mural thrombosis. Abdominal computed tomography scan revealed extension to the right renal vein and adhesion to the right kidney. The saccular aneurysm and the right kidney were resected, and anatomopathological examination revealed a cavernous hemangioma. All symptoms disappeared after surgery. This is the first reported case of symptomatic congenital saccular aneurysm of the IVC due to mural vascular malformation and with involvement of the right kidney leading to nephrectomy.


Assuntos
Aneurisma Roto/diagnóstico por imagem , Malformações Vasculares/diagnóstico por imagem , Veia Cava Inferior/diagnóstico por imagem , Dor Abdominal/diagnóstico por imagem , Dor Abdominal/patologia , Adulto , Aneurisma Roto/patologia , Humanos , Rim/irrigação sanguínea , Masculino , Veias Renais/diagnóstico por imagem , Trombose/diagnóstico por imagem , Trombose/patologia , Tomografia Computadorizada por Raios X , Veia Cava Inferior/anormalidades
15.
Inorg Chem ; 57(16): 9807-9813, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30070468

RESUMO

A series of Cu(III)-OH complexes supported by differently substituted bis(carboxamido)pyridine ligands is modeled to identify factors affecting electronic structure and hydrogen atom transfer reactivity. Activation of hydrocarbon substrates is inferred to be influenced by a combination of many factors, including overall charge state, counterion nature (when present), solvation, attractive and repulsive steric interactions, and quantum mechanical tunneling along the reaction coordinate.

16.
Phys Chem Chem Phys ; 20(36): 23467-23479, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30182123

RESUMO

The geometries of non-tetrahedral and ultrastable silicon and germanium nanocrystals X18H12 and X19H12 (X = Si, Ge) have recently been predicted for the development of cluster-based nanomaterials for energy and microengineering purposes. To further explore the possibility of larger Ge clusters, we investigated in this work the molecular and electronic structure of the germanium tube Ge30H12, composed of six parallel, planar hexagons using DFT calculations. Insertion of Ge atoms at the center of three inner hexagons of Ge30H12 leads to a Ge33H12 tube, which is also an energy minimum structure. The electronic structure and molecular orbital shapes of these tubes can be predicted by the wavefunctions of a particle on a hollow cylinder model and a cylinder model. Different aromaticity indices including PDI, Iring, ING, MCI, and INB, as well as the electron localization function (ELF) were calculated to evaluate the electron delocalization and the aromaticity of the Ge tubes considered.

17.
Faraday Discuss ; 201: 195-206, 2017 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-28613317

RESUMO

The metal-organic framework NU-1000, with Zr6-oxo, hydroxo, and aqua nodes, was modified by incorporation of hydroxylated Al(iii) ions by ALD-like chemistry with [Al(CH3)2(iso-propoxide)]2 followed by steam (ALD = atomic layer deposition). Al ions were installed to the extent of approximately 7 per node. Single-site iridium diethylene complexes were anchored to the nodes of the modified and unmodified MOFs by reaction with Ir(C2H4)2(acac) (acac = acetylacetonate) and converted to Ir(CO)2 complexes by treatment with CO. Infrared spectra of these supported complexes show that incorporation of Al weakened the electron donor tendency of the MOF. Correspondingly, the catalytic activity of the initial supported iridium complexes for ethylene hydrogenation increased, as did the selectivity for ethylene dimerization. The results of density functional theory calculations with a simplified model of the nodes incorporating Al(iii) ions are in qualitative agreement with some catalyst performance data.

18.
J Phys Chem A ; 120(16): 2550-60, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-27035753

RESUMO

A series of 11 different boron-dipyrromethene (BODIPY) dimers is carefully examined by means of ab initio and Tamm-Dancoff approximated density functional theory methods. Vertical and 0-0 excitation energies along with the tetraradical character of these dimers are determined. Possible application of a series of linked dimers for photodynamic therapy (PDT) was investigated through computing their excitation energies, spin-orbit coupling matrix elements, and singlet-triplet energy gaps. Finally through a systematic investigation of a series of 36 different BODIPY and aza-BODIPY dimers, a new class of near-IR heavy atom free photosensitizers for PDT action is introduced.


Assuntos
Compostos Aza/química , Compostos de Boro/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Teoria Quântica , Dimerização , Estrutura Molecular
19.
Nord J Psychiatry ; 70(4): 280-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26750863

RESUMO

Background and aims AIM2 is a component of inflammasomes which can activate caspase-1 via an adaptor protein (ASC) after pathogen-associated molecular pattern (PAMP) or danger-associated molecular pattern (DAMP) recognition. Activation of caspase-1 is a trigger for the induction of IL-1 and IL-18 which are important pro-inflammatory cytokines. Furthermore, IL-1ß, which can regulate inflammatory responses, has also been associated with depression. Previous studies revealed that patients suffering from depression may also have altered immune responses, but the mechanisms underlying this correlation are unclear. Thus, the aim of this study was to determine the mRNA levels of AIM2 and ASC in the peripheral blood mononuclear cells (PBMCs) isolated from Iranian medical students suffering from depression. Materials and methods The participants used for the study included 38 Iranian medical students diagnosed with depression and 43 non-depressed students as a control group. The mRNA levels of AIM2 and ASC were evaluated by quantitative real-time polymerase chain reaction (PCR) using ß-actin as a housekeeping gene for the normalization of expression. Results The results showed that mRNA levels of AIM2 were similar in both groups. However, ASC levels were significantly increased in PBMCs isolated from individuals with elevated depressive symptoms when compared to non-depressed participants. Conclusions Based on the current results, it appears that ASC transcript expression may be a surrogate marker for depression and may represent a link between depression and the altered immune responses observed in these categories of individuals with elevated depressive symptoms.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Depressão/metabolismo , Transtorno Depressivo/metabolismo , Estudantes de Medicina/psicologia , Adulto , Proteínas Adaptadoras de Sinalização CARD , Citocinas/metabolismo , Proteínas do Citoesqueleto/genética , Proteínas de Ligação a DNA/genética , Depressão/genética , Depressão/psicologia , Transtorno Depressivo/genética , Transtorno Depressivo/psicologia , Feminino , Humanos , Irã (Geográfico) , Leucócitos Mononucleares/metabolismo , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
20.
J Res Med Sci ; 21: 132, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28331518

RESUMO

BACKGROUND: The purpose of this study was to evaluate the influence of ejection fraction (EF) on peak aortic time (PAT) and peak aortic enhancement (PAE) during coronary computed tomography angiography (CTA). MATERIALS AND METHODS: One-hundred and twenty patients (64 men, 56 women) underwent measurement of coronary CTA with a measurement of EF within 3 months of coronary CTA. Pearson's correlation coefficient analysis was used to investigate the relationships between EF, PAT and PAE, and peak attenuation of all coronary arteries. RESULTS: The range of EF was (25%-70%) (mean: 55 ± 7.7). The range of PAT and PAE of ascending aorta on bolus test was 13-31 s (mean: 19.3 ± 2) and 153-435 HU (mean: 235 ± 40.6), respectively. Mean peak attenuation of ascending aorta, right coronary artery, left coronary artery, left circumflex artery, and left anterior descending were (561 ± 119), (476 ± 109), (505 ± 108), (467 ± 113), and (473 ± 104), respectively. There was a negative correlation between EF and PAT (r = -0.266, P = 0.003); however, there was no significant correlation between EF and PAE (r = -0.027, P = 0.767). In addition, there was no significant correlation between EF and the peak attenuation of coronary arteries. CONCLUSION: PAT was related to EF, but there was no relationship between PAE and EF. One of the explanation is that the left ventricular EF used for our study was assessed with echocardiography which is used roughly estimation of EF with interval of 5%-10% and may cause confounding results.

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