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1.
Mol Divers ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39117889

RESUMO

A multicomponent synthesis of 1,8-naphthyridine with high yields utilizing benzaldehydes, malononitrile, phenol, and acetylenic esters in aqueous solution at room temperature in the presence of SiO2/Fe3O4 as a reusable catalyst is reported. Using the MTT test, the cytotoxic properties of all the produced compounds were assessed in vitro against cancer cell lines (MCF-7 and A549) and normal cell lines (BEAS-2B). It was discovered that the most effective cytotoxic agent, doxorubicin-like in its lack of selectivity, was the derivative 5h. On the other hand, the compound 5c might be regarded as an equipotent molecule with greater selectivity in relation to doxorubicin. Also, this study investigates the antioxidant effects of 1,8-naphthyridine carboxylates, along with other studies conducted in this study.

2.
RSC Adv ; 13(47): 33390-33402, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37964904

RESUMO

The purpose of this review is to summarize the current literature on reductive C-N coupling of nitro compounds and boronic acids, with special emphasis on the mechanistic features of the reactions. The metal-catalyzed reactions are discussed first. This is followed by electro-synthesis and organophosphorus-catalyzed reactions. Finally, the available examples of catalyst-free reactions will be covered at the end of this review.

3.
RSC Adv ; 13(24): 16567-16583, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37274398

RESUMO

A CMC-g-poly(AA-co-AMPS)/Fe3O4 hydrogel nanocomposite was successfully designed and prepared via graft copolymerization of AA and AMPS on CMC followed by the cross-linking addition of FeCl3/FeCl2. The synthesized hydrogel nanocomposite was characterized by Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, elemental mapping, thermogravimetric analysis/differential thermal analysis (TGA/DTA), and vibrating sample magnetometry (VSM). The CMC-g-poly(AA-co-AMPS)/Fe3O4 hydrogel nanocomposite was employed as a biocompatible catalyst for the green synthesis of 1,4-dihydropyridine (1,4-DHP) derivatives under thermal and ultrasound-assisted reaction conditions. High efficiency, low catalyst loadings, short reaction time, frequent catalyst recovery, environmental compatibility and mild conditions were found in both methods.

4.
J Mol Graph Model ; 118: 108317, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36162160

RESUMO

We are investigated substitution effects of titanium heteroatoms on band gap, charge and local reactivity of C20-nTin heterofullerenes (n = 1-5), at different levels and basis sets. The C18Ti2-2 nanocage is considered as the most kinetically stable species with the widest band gap of 2.86 eV, in which two carbon atoms are substituted by two Ti atoms in equatorial position, individually. The charges on carbon atoms of C20 are roughly zero, while high positive charge (1.256) on the surface of C19Ti1 prompts this heteofullerene for hydrogen storage. The positive atomic charge on Ti atoms and negative atomic charge on their adjacent C atoms implies that these sites can be influenced more readily by nucleophilic and electrophilic regents, respectively. We examined the usefulness of local reactivity descriptors to predict the reactivity of Ti-C atomic sites on the external surface of the heterofullerenes. The properties determined include Fukui function (F.F.); f (k) and local softness s (k) on the surfaces of the investigated hollow cages. Geometry optimization results reveal that titanium atoms can be comfortably incorporated into the CC network of fullerene. It is most likely associated with the triple-coordination characteristic of titanium atoms, which can well match with the sp2-hybridized carbon bonding structure. According to the values of f (k) and s (k) for the C15Ti5 heterofullerene; the carbon atoms in the cap regions exhibit a different reactivity pattern than those in the equatorial portion of the heterofullerene. The titanium impurity can significantly improve the fullerene's surface reactivity and it allows controlling their surface properties. The band gap of C20-nTin …..(H2)n structures is decreased with increasing n. Hence, C15Ti5 is found as the best hydrogen adsorbent.


Assuntos
Fulerenos , Titânio , Titânio/química , Modelos Moleculares , Fulerenos/química , Química Computacional , Hidrogênio/química , Carbono/química
5.
Front Chem ; 10: 1001707, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262344

RESUMO

We applied the Petasites hybridus rhizome water extract as green media so that Ag/Fe3O4/CdO@ multi-walled carbon nanotubes magnetic nanocomposites (Ag/Fe3O4/CdO@MWCNTs MNCs) could be prepared. We also evaluated its activity by using in the one-pot multicomponent reaction of acetophenones, diethyl oxalate, ammonium acetate, and activated carbonyl compounds such as ninhydrin, isatin and acenaphthylene-1,2-dione, and malononitrile and hydrazoyl chlorides in an aqueous medium at room temperature for the generation of spiro-1,2,4-triazines as new derivatives with tremendous output. Moreover, reducing organic pollutants from 4-nitrophenol (4-NP) was carried out by generating Ag/Fe3O4/CdO@MWCNTs in water at room temperature. The results displayed that Ag/Fe3O4/CdO@MWCNTs reduced pollutants of organic compounds in a short time. The synthesized spiro-1,2,4-triazines have NH and OH functional groups having acidic hydrogen with high antioxidant power. Also, the spiro-1,2,4-triazines exhibited antimicrobial ability. For this purpose, the disk diffusion method was applied and two kinds of bacteria, Gram-positive and Gram-negative, were employed for the analysis. Furthermore, we applied functional theory-based quantum chemical methods in order to better understand reaction mechanism density. To generate spiro-1,2,4-triazines, the applied process showed many properties such as reactions with short time, products with good yields, and simple extraction of catalyst from a mixture of reactions.

6.
Cell J ; 23(6): 674-683, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34939761

RESUMO

OBJECTIVE: Alimta (Pemetrexed) as an antifolate drug has been approved for the treatment of lung cancer. The aim of the present study was to investigate the combination effect of 5-Azacytidine (5-aza) and Alimta on the miR-34a and its target genes expression and induction of apoptotic cell death in non-small lung cancer A549 cells. MATERIALS AND METHODS: In this experimental study, lung cancer A549 cells were treated with various concentrations of Alimta alone and combined with 5-Aza. Then, viability was assessed by trypan blue and MTT assays. mRNA expressions were performed by real time-polymerase chain reaction (PCR) and western blot. Flow cytometry used to detect apoptotic/ necrotic cells and cell cycle arrest. RESULTS: Alimta alone reduced viability of the cells in a dose dependent manner with the half-maximal inhibitory concentration (IC50) value of 12 µM. Pretreatment of the cells with 5-aza (5 µM) induced a synergistic cytotoxic effect with IC50 of 3 µM. Sequential exposure of the cells to 5-aza and Alimta enhanced miR-34a expression and significantly downregulated HMGB1, HMGA2 and BCL-2 expressions. Also, it was associated with reduction of nuclear HMGB1 and HMGA2 content. Caspase-3 activation, HMGB1 release into extracellular space and staining of the cells with annexine V/PI suggested that 5-aza reduced late apoptotic/necrotic cell death induced by Alimta. In addition, combination of 5-aza and Alimta arrested the cells at S and sub-G1 phases and inhibited colony formation. CONCLUSION: 5-aza synergistically enhances Alimta induced apoptotic cell death through HMG proteins regulation, MIR34A gene expression and intrinsic apoptosis mechanism, providing a promising combination therapy in clinical lung cancer therapy.

7.
RSC Adv ; 11(51): 32513-32525, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-35495514

RESUMO

Among the wide variety of synthetic transformations of inexpensive and abundant feedstock alkenes, vicinal difunctionalization of carbon-carbon double bonds represent one of the most powerful and effective strategies for the introduction of two distinct functional groups into target compounds in a one-pot process. In this context, the direct alkoxysulfenylation of alkenes has emerged as an elegant method to construct valuable ß-alkoxy sulfides in an atom- and pot-economic manner utilizing readily accessible starting materials. Here, we review the available literature on this appealing research topic by hoping that it will be beneficial for eliciting further research and thinking in this domain.

8.
Mol Divers ; 25(1): 67-86, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31927717

RESUMO

Novel sulfonated carbon-coated magnetic nanoparticles (SCCMNPs; Fe3O4@C@OSO3H) were designed, synthesized, characterized, and applied as an efficient nanocatalyst for green synthesis of coumarin derivatives through Pechmann condensation. The Fe3O4@C@OSO3H was manufactured through a simple and inexpensive two-step procedure and characterized by FTIR, EDX, XRD, SEM, TEM, DLS, VSM, and TGA techniques. It was identified as an efficient heterogeneous catalyst in the Pechmann condensation of phenol derivatives and ß-ketoesters, leading to high-yield coumarin derivatives under solvent-free conditions. The Fe3O4@C@OSO3H removed after reaction finishing point by an external magnet, and it was reused fifteen times at the same conditions. Besides, theoretical studies were carried out using B3LYP/6-311++G(d,p) to more consideration of the reaction mechanism. The study of the frontier molecular orbitals, NBO atomic charges, molecular electrostatic potential of reactants, as well as Pechmann condensation mechanism was known very useful in suitable reactant choice. The reaction was performed through the electrophilic attack, dehydration, and trans-esterification, respectively.


Assuntos
Compostos Férricos/química , Nanopartículas de Magnetita/química , Carbono/química , Catálise , Cumarínicos/química , Ésteres/química , Química Verde/métodos , Solventes/química
9.
Toxicol Appl Pharmacol ; 396: 114996, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278510

RESUMO

Antineoplastic drugs cause severe cytotoxicity for normal cells, especially hematopoietic stem cells (HSCs). However, bleomycin (BLM) is glycopeptide antibiotic that is effective on various cancers and has either low or no myelosuppression effects. The aim of the present study was to investigate the effect of BLM on 5-Azacitidine (5-AZA) induced cytotoxicity in bone marrow HSCs. 5-AZA reduced HSC cell viability in a time and dose-dependent manner with an IC50 value of 16 µM. However, pretreatment of the cells with BLM for 4 h induced an antagonistic cytotoxicity with an increased IC50 of 64 µM. 5-AZA decreased the colony formation ability of HSC cells in semi-solid agar culture and this effect was attenuated by BLM. 5-AZA significantly downregulated high mobility group Box1 (HMGB1) and Bcl-2 gene expression but upregulated Bax gene expression, while BLM impeded the action of 5-AZA. Pretreatment with BLM remarkably decreased HMGB1 release into culture media that was induced by 5-AZA. The cells were distribution at the sub/G1 phase. Annexin/PI staining of the cells, poly (ADP-ribose) polymerase (PARP) cleavage, and anion superoxide production indicated that BLM limited 5-AZA induced apoptotic cell death. In conclusion, BLM in combination with 5-AZA effectively reduces the adverse cytotoxic effects of 5-AZA on bone marrow hematopoietic stem cells, providing a new chemotherapeutic strategy.


Assuntos
Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Azacitidina/toxicidade , Bleomicina/farmacologia , Proteína HMGB1/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo , Animais , Azacitidina/antagonistas & inibidores , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismo
10.
BMC Infect Dis ; 20(1): 12, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906872

RESUMO

BACKGROUND: Determination of the prevalence and distribution pattern of intestinal parasites is a fundamental step to set up an effective control program to improve the health status. This study aimed to determine the prevalence of intestinal parasitic infections and associated risk factors among inhabitants of Rudbar-e Jonub county, southeast of Kerman province, southeastern Iran. METHODS: In this cross-sectional study, 861 stool specimens were collected from inhabitants of Rudbar-e Jonub county through a multistage cluster sampling method in 2018. The collected specimens were examined by parasitological methods including, direct wet-mounting (for the fresh specimens with a watery consistency), formalin-ethyl acetate sedimentation and agar plate culture. RESULTS: The prevalence of intestinal parasites was 34.2% (95% CI 30.1 to 38.2). The prevalence of protozoan parasites 32.3% (95% CI 28.4 to 36.5) was significantly higher than helminthic parasites 3.2% (95% CI 2.1 to 4.7). Blastocystis sp. (13.3%), Entamoeba coli (11.4%) and Giardia lamblia (10.6%) as protozoan parasite and Hymenolepis nana (2.4%) as helminthic parasite were the most common detected intestinal parasites in the study. Entamoeba histolytica/dispar (1.5%), Iodamoeba bütschlii (1.0%), Chilomastix mesnili (0.5%), Entamoeba hartmanni (0.4%), Enterobius vermicularis (0.3%) and Ascaris lambercoides (0.3%) were other detected parasites. Multiple logistic regression revealed a significant association of intestinal parasitic infections with source of drinking water and residency status (rural/urban). Multiple infections with 2 or 3 parasitic agents constituted 22.7% of 295 infected cases. CONCLUSIONS: This study revealed a high prevalence of intestinal protozoan infections among inhabitants of Rudbar-e Jonub county. Intestinal parasites especially protozoans remain a challenging public health problem wherever sanitation and health measures are limited in Iran.


Assuntos
Enteropatias Parasitárias/epidemiologia , Adolescente , Adulto , Animais , Criança , Estudos Transversais , Fezes/parasitologia , Feminino , Helmintíase/epidemiologia , Helmintíase/parasitologia , Humanos , Enteropatias Parasitárias/parasitologia , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Parasitos/classificação , Prevalência , Infecções por Protozoários/epidemiologia , Infecções por Protozoários/parasitologia , Fatores de Risco , Adulto Jovem
11.
Exp Clin Transplant ; 15(2): 231-234, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-26788941

RESUMO

Diabetes mellitus is a disease with no definite cure. In recent years, stem cell transplant has led to treatment of various diseases including diabetes. We sought to report a type 1 diabetic patient with a brain mass, diagnosed as transitional meningioma, after a fetal hematopoietic stem cell transplant. A 57-year-old woman with type 1 diabetes who previously had undergone a fetal hematopoietic stem cell transplant, attended the clinic with a history of progressive bifrontal headaches accompanied by nausea, vomiting, and visual disturbances over the previous 8 months. Investigations revealed a 2-cm mass in the right temporal region. The patient underwent a craniotomy, and the lesion was removed and sent for pathological and genetic investigations. The results indicated transitional meningioma with the origin of transplanted fetal hematopoietic stem cells. To our knowledge, this is the first report of transitional meningioma as a result of stem cell transplant. Despite all unanswered questions about the safety of stem cell transplant, this novel therapy provides hope for patients with type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Células-Tronco Fetais/transplante , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neoplasias Meníngeas/etiologia , Meningioma/etiologia , Craniotomia , Diabetes Mellitus Tipo 1/diagnóstico , Feminino , Células-Tronco Fetais/patologia , Humanos , Imageamento por Ressonância Magnética , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/cirurgia , Meningioma/diagnóstico , Meningioma/cirurgia , Pessoa de Meia-Idade , Resultado do Tratamento , Carga Tumoral
12.
Artigo em Inglês | MEDLINE | ID: mdl-26207222

RESUMO

BACKGROUND: Rapidly increasing prevalence of diabetes throughout the world highlights the importance of looking for new treatment options for the disease such as stem cell therapy. With regard to the increasing attention towards stem-cell therapy as a curative treatment for diabetes in recent years, it is of crucial importance to ensure the safety of this novel therapeutic technique. In this study we aim to evaluate the safety of fetal liver-derived cell suspension allotransplantation in the diabetic patients who had attended a clinical trial in 2007. METHODS: 44 out of a total number of 56 patients who had undergone either fetal liver-derived cell suspension allotransplantation or placebo injection in 2007 (IRCT number: 138811071414 N10) were contacted and recruited for the evaluation of possible complications. Patients were referred to a designated ophthalmologist and cardiologist to be screened for retinopathy and cardiovascular diseases. 24-hour urine was collected and tested for the evaluation of nephropathy; and, neuropathy was assessed by means of neuropathic symptoms and monofilament test. RESULTS: There were no life-threatening complications nor significant differences in terms of evaluated diabetes complications ( retinopathy, neuropathy, nephropathy and cardiovascular diseases ) between the case and control groups. However, one case of meningioma was reported. CONCLUSIONS: Findings of our study demonstrated that stem cell transplantation can be considered a relatively safe procedure apart from one case of meningioma; it did neither cause any life-threatening complications nor increased the rate of the diabetes micro- and macrovascular complications.

13.
Basic Clin Neurosci ; 6(3): 155-62, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26904172

RESUMO

INTRODUCTION: Recent studies suggest that glucocorticoids modulate memory reconsolidation. Moreover, cholinergic system is involved in memory reconsolidation. Since glucocorticoids interact with brain cholinergic system in modulating memory processing, we investigated whether glucocorticoid influences on the reconsolidation of emotionally arousing training depend on the cholinergic system. METHODS: Mice were trained (1mA, 3s footshock) in an inhibitory avoidance task. Forty-eight hours after training, memory reactivation was occurred (Test 1), and different treatments were given. Two (Test 2), five (Test 3), and seven days (Test 4) after memory reactivation (Test 1), animals were retested for fear memory retention. RESULTS: In the first experiment, we observed that administration of corticosterone (CORT, 0.3, 1 and 3 mg/kg) following memory reactivation impaired subsequent expression of memory in a dose-dependent manner. In the second experiment, we found that CORT-induced impairment of memory reconsolidation was reversed by the muscarinic receptor antagonist atropine (0.5 and 2 mg/kg). In the third experiment, the nicotinic receptor antagonist mecaylamine (0.5 or 2 mg/kg) was not able to block the corticosterone response. DISCUSSION: These findings indicate that glucocorticoids impair memory reconsolidation by a muscarinic cholinergic mechanism.

15.
Acta Med Iran ; 50(2): 79-96, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22359076

RESUMO

Stem cells are undifferentiated cells with the ability of proliferation, regeneration, conversion to differentiated cells and producing various tissues. Stem cells are divided into two categories of embryonic and adult. In another categorization stem cells are divided to Totipotent, Multipotent and Unipotent cells.So far usage of stem cells in treatment of various blood diseases has been studied (such as lymphoblastic leukemia, myeloid leukemia, thalassemia, multiple myeloma and cycle cell anemia). In this paper the goal is evaluation of cell therapy in treatment of Parkinson's disease, Amyotrophic lateral sclerosis, Alzheimer, Stroke, Spinal Cord Injury, Multiple Sclerosis, Radiation Induced Intestinal Injury, Inflammatory Bowel Disease, Liver Disease, Duchenne Muscular Dystrophy, Diabetes, Heart Disease, Bone Disease, Renal Disease, Chronic Wounds, Graft-Versus-Host Disease, Sepsis and Respiratory diseases. It should be mentioned that some disease that are the target of cell therapy are discussed in this article.


Assuntos
Transplante de Células-Tronco , Doença de Alzheimer/terapia , Esclerose Lateral Amiotrófica/terapia , Animais , Humanos , Doenças Inflamatórias Intestinais/terapia , Esclerose Múltipla/terapia , Distrofia Muscular de Duchenne/terapia , Doença de Parkinson/terapia , Traumatismos da Medula Espinal/terapia
16.
Brain Inj ; 23(10): 815-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19697170

RESUMO

PRIMARY OBJECTIVE: To assess the inter-rater reliability of the Modified Modified Ashworth Scale (MMAS) in lower limb muscle spasticity. RESEARCH DESIGN: Cross-sectional observational study. INTERVENTIONS: Not applicable. METHODS AND PROCEDURES: Twenty-two adults with neurological conditions (17 women, five men, age range 21-82 years; mean +/- SD, 44 +/- 18 years) participated. Hip adductor, knee extensor and ankle plantarflexor were assessed in a random order. MAIN OUTCOMES AND RESULTS: Inter-rater agreement for two raters was very good for the hip adductor and the knee extensor (weighted kappa = 0.82, p < 0.0001) and good for the ankle plantarflexor (weighted kappa = 0.74, p < 0.0001). CONCLUSIONS: The Modified Modified Ashworth Scale produced reliable measurements between raters in the assessment of lower limb muscle spasticity.


Assuntos
Esclerose Múltipla/complicações , Espasticidade Muscular/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Irã (Geográfico) , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Espasticidade Muscular/reabilitação , Variações Dependentes do Observador , Índice de Gravidade de Doença , Reabilitação do Acidente Vascular Cerebral , Adulto Jovem
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