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1.
Inorg Chem ; 62(33): 13387-13399, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37560902

RESUMO

Regeneration of terminal oxidants by molecular oxygen in metal-catalyzed oxidations of organic substrates has the advantage of avoiding the use of stoichiometric amounts of hazardous and/or expensive reagents to meet (some of) the green chemistry requirements. In the present study, photosensitized singlet oxygen oxidation of iodate to periodate has been used to regenerate the oxidant in polyoxometalate (POM)-catalyzed oxidation of sulfides to sulfoxides with periodate in water. To the best of our knowledge, it is the first report on singlet oxygen oxidation of iodate to periodate. In order to determine the contribution of photooxidation and oxidation pathways in the formation of sulfoxide, the oxidation of diphenyl sulfide with a very low reactivity toward aerobic photooxidation was studied; a sevenfold increase in the conversion of the sulfide to the diphenyl sulfoxide was observed for the reaction conducted in the presence of H2TMPyP-PW12O40/IO3-/O2/hν compared to that in the presence of H2TMPyP-PW12O40/O2/hν. Also, under the same conditions, a ca. 1.5-fold increase was observed in the case of methyl phenyl sulfide, which shows high reactivity toward both the oxidation and photooxidation reactions. A porphyrin-POM nanocomposite formed by the electrostatic immobilization of meso-tetra(N-methylpyridinium-4-yl)porphyrin (H2TMPyP) on PW12O40 was employed for the one-pot oxidation and photooxidation reactions. Field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), diffuse-reflectance UV-vis spectroscopy, thermal gravimetric analysis, and Fourier transform infrared were used to characterize the formation of the hybrid compound. An average particle size of 42 nm was estimated for H2TMPyP-PW12O40 from XRD peak broadening using the Scherrer equation. Also, FESEM images showed the formation of nearly spherical nanoparticles with a size of ca. 200 nm. The redshift of the Soret band of H2TMPyP upon immobilization on POM was attributed to strong N-H···O hydrogen-bond interactions between POM and porphyrin.

2.
Inorg Chem ; 62(14): 5468-5478, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36992610

RESUMO

From the environmental protection and human health perspectives, the design and synthesis of efficient and reusable oxidative desulfurization nanocatalysts has always been sought after by scientists and industries. In this regard, a new heterogeneous nanocatalyst (V-SPM@PANI@CH) was synthesized by immobilizing Keggin-type vanadium-substituted phosphomolybdate ([PVMo11O39]4-) (named V-SPM) clusters on the surface of polyaniline (PANI) and chitosan (CH) polymers. The features of the assembled nanocatalyst were detected by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy, and energy-dispersive X-ray spectroscopy techniques in detail. The XRD studies indicated that the average crystallite size of V-SPM@PANI@CH was estimated to be about 36 nm. The catalytic performance of V-SPM@PANI@CH was investigated in the extractive and catalytic oxidation desulfurization (ECOD) procedure of real and thiophenic model gasoline by H2O2/AcOH (volume proportion of 2:1) as an oxidizing system. The optimal desulfurization conditions for ECOD reactions were as follows: 50 mL of model/real gasoline, 0.1 g of V-SPM@PANI@CH, reaction time of 60 min, and reaction temperature of 35 °C. Under the experimental conditions outlined above and the designed ECOD system, the content of sulfur in real gasoline could decline from 0.4985 to 0.0193 wt %, which corresponds to an efficiency of 96%. Moreover, the removal percentage of aromatic hydrocarbons, including thiophene (Th), benzothiophene (BT), and di-benzothiophene (DBT) as model fuels decreases in the order of DBT ≥ BT > Th under identical operating conditions. High catalytic activity was maintained with only a slight loss during five cycles. This work offers the ECOD system (V-SPM@PANI@CH/AcOH/H2O2) for the desulfurization of liquid fuels, which had a great repercussion on the ECOD efficiency.

3.
Reprod Domest Anim ; 58(4): 537-547, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36645789

RESUMO

A hypothesis was tested that quantitative feed restriction affects the reproductive performance and offspring sex ratio of female Chukar breeder partridges. A total of 160 2.5-year-old male and female partridges were randomly allotted to four treatment groups. The birds in the control group were fed ad libitum, whereas those in treatments G95 , G90 , and G85 received 26.1, 24.7, and 23.3 g of feed per bird/day to provide 95%, 90%, and 85% of ad libitum feeding level, respectively. The reproductive performances of female Chukar partridges including egg production, egg quality, fertility rate, duration of fertility, hatchability, chick quality, mortality rate, and offspring sex ratio (using a PCR procedure) were investigated. Feed restriction of all levels decreased the body weight and egg production compared with the ad libitum birds; however, restricted feeding had no significant effect on the egg quality traits. Non-significant effects of treatment on fertility and hatchability rate were found. The restricted feeding reduced the duration of fertility. Furthermore, maternal restricted feeding resulted in decreased chick weights. The results of this study showed that embryonic mortality was not affected by the restricted feeding of Chukar breeder partridges. Interestingly, restricted feeding was associated with a decreased proportion of male offspring. Overall, body weight, egg production, duration of fertility, progeny chick weight, and sex ratio were responsive to restricted feeding where their changes make the restricted feeding regimens to not be practically recommended in breeder partridge production. These results are in contrast to the conventional restricted feeding program implemented in broiler breeder industry.


Assuntos
Galliformes , Animais , Feminino , Masculino , Peso Corporal , Reprodução , Razão de Masculinidade
4.
Environ Geochem Health ; 45(12): 9495-9505, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37358715

RESUMO

Finding a method, which may indicate the contribution of soil parameters including organic matter, pH and clay to pretilachlor leaching (persistence) in the soil, with the use of a suitable indicator, which indicates pretilachlor presence in the soil is of significance. Accordingly, using undisturbed soil columns, four paddy fields (A, B, C, D) in the suburbs of Babol city (Mazandaran province, northern Iran) were sampled before the preparation and irrigation of the fields in April 2021. Soil samples were transferred into PVC pipes (divided into 2 cm layers) measuring 12 (height) × 10 cm (diameter), and were injected with pretilachlor at the recommended (1.75 L/ha) and high doses (3.5 L/ha). The surface layers of all fields had a higher concentration of pretilachlor and organic matter with the highest contribution to pretilachlor persistence followed by clay and pH. In the 0-4 cm depth, herbicide concertation was the lowest in field A (139 mg/kg) and the highest in field C (161 mg/kg). The corresponding values for organic matter were equal to 1.88 and 5.68%, respectively. The bioassay of rice (the indicator plant), with a significant correlation with chemical analysis results, indicated field A and field C had the pretilachlor infiltration of 6 and 4 cm, respectively. Accordingly, rice is a suitable plant indicator for measuring the presence of pretilachlor as examining its shoot length is a good criterion for bioassay. Additionally, changes in the amount of organic matter in different soil layers can be used to predict the leaching level of pretilachlor.


Assuntos
Herbicidas , Oryza , Solo , Argila , Acetanilidas/análise , Herbicidas/análise , Plantas
5.
Technol Forecast Soc Change ; 193: 122633, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37223653

RESUMO

While there have been numerous studies investigating the impact of the COVID-19 pandemic on tourism, few research projects have examined the impact of the outbreak on using smart tourism technologies (STT), especially in developing countries. This study adopted thematic analysis, with data collected using in-person interviews. The participants for the study were selected using the snow-balling technique. We explored the process of developing smart technologies during the pandemic and its impact on smart rural tourism technology development upon travel restart. The subject was investigated by focusing on five selected villages in central Iran which have tourism dependent economies. Overall, the results indicated that the pandemic partially changed the government's resistance towards the fast development of smart technologies. Thus, the role of smart technologies in curbing the virus spread was officially recognized. This change of policy led to the implementation of Capacity Building (CB) programs to improve digital literacy and minimize the digital gap that exists between urban and rural areas in Iran. Implementing CB programs during the pandemic directly and indirectly contributed to the digitalization of rural tourism. Implementing such programs enhanced tourism stakeholders' individual and institutional capacity to gain access to and creatively use STT in rural area. The results of this study improve our understanding and knowledge of the impact of crises on the degree of acceptability and use of STT in traditional rural societies.

6.
Bull Environ Contam Toxicol ; 108(1): 151-157, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34476543

RESUMO

More has yet to be indicated on the adsorption and degradation processes, determining herbicides recycling in the environment. The sorption and degradation of 2, 4-D, affected by organic carbon (1.92-2.81%), soil clay (20-30%) and pH of the citrus orchards of Mazandaran province, Iran was investigated using HPLC equipped with UV detector for the identification and quantification of soil 2, 4-D. The adsorption (kd) and degradation (Kdeg) coefficients were determined using Freundlich and the first-degree kinetic equations. Gardens C (2.45 mL g-1), and B (0.3 mL g-1), with the highest (8.2 g day-1) and least (2.7 g day-1) degradation coefficients, had the highest and lowest Kd values. Kd variations with pH indicated higher adsorption of 2, 4-D in acidic pH. Due to the high presence of functional groups and soil biological activities, organic carbon affected the adsorption and degradation rates more effectively, which is of economic and environmental significance.


Assuntos
Herbicidas , Poluentes do Solo , Adsorção , Carbono , Argila , Herbicidas/análise , Solo , Poluentes do Solo/análise
7.
Reprod Fertil Dev ; 33(7): 447-454, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33751926

RESUMO

Polycystic ovary syndrome (PCOS) is one of the most common ovarian diseases among women of reproductive age. The reproductive and metabolic traits of PCOS are underpinned by adipocyte dysfunction, especially diminished adiponectin secretion. Based on evidence that niacin stimulates adiponectin secretion, this study evaluated the effects of niacin on adiponectin concentrations and reproductive traits in a rat model of PCOS. PCOS was induced by single injection of 4mg kg-1 oestradiol valerate (i.m.), and PCOS groups were administered orally with saline or niacin (10 or 25mg kg-1) daily for 30 days after PCOS induction. The control group received 0.2mL sesame oil (i.m.) only. At the end of the experimental period, serum samples and ovaries were collected for adiponectin, histological and molecular analyses. Niacin reduced the bodyweight gain and increased ovary weights in PCOS rats. Niacin also increased the number of normal antral follicles and corpora lutea while reducing the number of cystic follicles and the thickness of theca interna. Moreover, niacin significantly increased serum adiponectin concentration and the gene expression of adiponectin and its type 1 receptor. In conclusion, this study indicates that niacin reduces cystic follicles and improves ovulation in PCOS rats. Adiponectin signalling may have contributed, in part, to the beneficial effects.


Assuntos
Adiponectina/sangue , Niacina/administração & dosagem , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Síndrome do Ovário Policístico/tratamento farmacológico , Administração Oral , Animais , Modelos Animais de Doenças , Feminino , Tamanho do Órgão , Folículo Ovariano/metabolismo , Folículo Ovariano/patologia , Folículo Ovariano/fisiopatologia , Ovário/metabolismo , Ovário/patologia , Ovário/fisiopatologia , Ovulação/efeitos dos fármacos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/patologia , Síndrome do Ovário Policístico/fisiopatologia , Ratos Wistar , Receptores de Adiponectina/genética , Receptores de Adiponectina/metabolismo , Aumento de Peso/efeitos dos fármacos
8.
Andrologia ; 53(6): e14022, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33942906

RESUMO

Zona pellucida (ZP)-bound spermatozoa have normal morphology and motility and can enhance the ICSI outcomes. Selection of zona pellucida-bound spermatozoa is recently considered to find functional spermatozoa for ICSI. This study reviewed the efficacy of ZP-bound sperm selection on the ICSI outcomes includes fertilisation rate, embryo quality, embryo transfer rate and clinical pregnancy rate. The databases searched include PubMed, Scopus and Cochrane databases up to January 2019. All research reports with full text and in English language that addressing the relation between ZP-sperm selection and ICSI outcomes were included. Fifty studies were suitable after screening of the 845 identified articles. After exclusions, five of these studies were included. Meta-analytic pooling of data indicated no association between the ICSI outcomes and ZP-bound sperm selection except a marginal effect on implantation rate. Eliminating one study indicated that ZP-bound sperm selection technique improves embryo quality, implantation rate and clinical pregnancy rate. This study revealed that ZP-bound sperm selection produces only a slight improvement in implantation rate. However, further studies with a large number of couples must be done to clarify the potential beneficial effect of ZP-bound spermatozoa on ICSI outcomes.


Assuntos
Interações Espermatozoide-Óvulo , Zona Pelúcida , Feminino , Humanos , Masculino , Gravidez , Seleção Genética , Injeções de Esperma Intracitoplásmicas , Espermatozoides
9.
Trop Anim Health Prod ; 53(5): 486, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34586503

RESUMO

The aim of this study was to evaluate the effects of partial replacement of forage and concentrate with pomegranate pulp silage (PPS) and dried pomegranate seed pulp (PSP) on performance, dry matter intake (DMI), and carcass characteristics of fattening Mehraban lambs. Twenty-four male lambs (mean body weight 27.0 ± 3.5 kg) were fed with three isonitrogenous and isoenergetic diets (n = 8 per diet), consisting of a control diet, a PPS diet containing 27.2% pomegranate pulp silage, and a PSP diet containing 31.4% dried pomegranate seed pulp. The experimental diets were fed ad libitum as total mixed rations for 65-day fattening period, on two meals per day, and then the growth performance, feed intake, and carcass characteristics were determined. The initial BW, final BW, average daily gain (ADG), and feed conversion ratio (FCR) were not different among the experimental diets. The amount of DMI in PSP diet was higher than that in the control diet (P = 0.023) but was not different between the control and PPS diets. There was no significant difference among diets for carcass characteristics. Using PPS and PSP in the diets decreased (P < 0.05) the kidney fat, but had no impact on the heart, liver, kidneys, spleen, and lungs. The results showed that PPS and PSP could be used to replace part of the diet for fattening lambs, while decreasing the dietary cost without having any negative effects on animal performance.


Assuntos
Punica granatum , Silagem , Ração Animal/análise , Animais , Sementes , Ovinos , Carneiro Doméstico , Silagem/análise
10.
Gen Dent ; 69(3): 68-72, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33908882

RESUMO

The fracture of restorations used for diastema closure is a clinical concern. The objective of this study was to perform a finite element-based comparative analysis of functional stress patterns in composite resin veneer restorations used for diastema closure to determine the influence of factors such as the preparation design, proximal extension, loading level, and vector of stress (loading angle). Three-dimensional finite element stress analysis was performed on a maxillary central incisor model to examine the stress distribution resulting from a nanofilled composite veneer restoration with 4 different extensions of unsupported composite (0.5, 1.0, 1.5, or 2.0 mm) and 2 different preparation designs (partial or full) under 3 loads (50, 150, or 250 N) and 3 loading angles (60°, 90°, or 125°). The maximum stress was found to be concentrated on the full-preparation design with a 0.5-mm mesial extension under a 250-N load and 60° loading angle. The minimum stress was found with the partial-preparation design with a 0.5-mm mesial extension under a 50-N load and 90° loading angle. Based on the results of the present study, a partial-preparation design is preferred when nanofilled composite resins are used for diastema closure.


Assuntos
Diastema , Resinas Compostas , Porcelana Dentária , Análise do Estresse Dentário , Facetas Dentárias , Diastema/terapia , Análise de Elementos Finitos , Humanos , Estresse Mecânico
11.
J Cell Physiol ; 235(10): 6969-6977, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32026477

RESUMO

Inflammatory cytokine, interleukin-6 (IL-6), plays an important role in the pathogenesis of cardiac hypertrophy. Recent studies have documented that resveratrol exhibits cardioprotective effects. The present study attempts to explore whether resveratrol suppreses IL-6 in hypertrophied H9c2 cardiomyoblasts through histone deacetylase, sirtuin 1 (SIRT1). To induce hypertrophy, the cells were incubated with angiotensin II (Ang II). Treatment groups were treated with different doses (1, 10, 25, 50, 75, and 100 µM) of resveratrol (R). Cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Cell size was determined using crystal violet staining. Gene expression was assessed by real-time polymerase chain reaction technique. Enzyme-linked immunosorbent assay was used to measure IL-6 concentration. The results showed that cell area and ANP messenger RNA (mRNA) levels decreased significantly in R25+Ang, R50+Ang, and R100+Ang groups, as compared with Ang group. Therefore, 10, 20, 30, 40, and 50 µM of resveratrol were used to to evaluate its anti-inflammatory effects. The results revealed that Ang II upregulated IL-6 at both mRNA and protein levels (p < .001 vs. normal) and resveratrol (50 µM) decreased IL-6 mRNA (p < .01) and protein (p < .05) significantly in comparison to Ang group. However, in groups in which the cells were pretreated with SIRT1 inhibitor, EX-527, the response of resveratrol was partially reversed. Transcription levels of IL-6 receptor components (gp130 and gp80) did not change significantly among the experimental groups. The current data suggests that resveratrol protects H9c2 cells against Ang II-induced hypertrophy by suppression of IL-6 through SIRT1 activation.


Assuntos
Cardiomegalia/tratamento farmacológico , Cardiomegalia/metabolismo , Interleucina-6/metabolismo , Resveratrol/farmacologia , Sirtuína 1/metabolismo , Angiotensina II/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Miócitos Cardíacos , RNA Mensageiro/metabolismo , Ratos , Transcrição Gênica/efeitos dos fármacos
12.
Eur J Clin Microbiol Infect Dis ; 38(11): 2005-2019, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31372904

RESUMO

Human oral cavity (mouth) hosts a complex microbiome consisting of bacteria, archaea, protozoa, fungi and viruses. These bacteria are responsible for two common diseases of the human mouth including periodontal (gum) and dental caries (tooth decay). Dental caries is caused by plaques, which are a community of microorganisms in biofilm format. Genetic and peripheral factors lead to variations in the oral microbiome. It has known that, in commensalism and coexistence between microorganisms and the host, homeostasis in the oral microbiome is preserved. Nonetheless, under some conditions, a parasitic relationship dominates the existing situation and the rise of cariogenic microorganisms results in dental caries. Utilizing advanced molecular biology techniques, new cariogenic microorganisms species have been discovered. The oral microbiome of each person is quite distinct. Consequently, commonly taken measures for disease prevention cannot be exactly the same for other individuals. The chance for developing tooth decay in individuals is dependent on factors such as immune system and oral microbiome which itself is affected by the environmental and genetic determinants. Early detection of dental caries, assessment of risk factors and designing personalized measure let dentists control the disease and obtain desired results. It is necessary for a dentist to consider dental caries as a result of a biological process to be targeted than treating the consequences of decay cavities. In this research, we critically review the literature and discuss the role of microbial biofilms in dental caries.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cárie Dentária/microbiologia , Microbiota/fisiologia , Boca/microbiologia , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Cárie Dentária/genética , Cárie Dentária/prevenção & controle , Doenças da Polpa Dentária/genética , Doenças da Polpa Dentária/microbiologia , Doenças da Polpa Dentária/prevenção & controle , Gengiva/microbiologia , Gengiva/fisiologia , Humanos , Doenças Periodontais/genética , Doenças Periodontais/microbiologia , Doenças Periodontais/prevenção & controle , Saliva/química
13.
J Prosthodont ; 28(1): e172-e180, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28273681

RESUMO

PURPOSE: To evaluate the effect of overglazing and two polishing procedures on flexural strength and quality and quantity of surface roughness of a monolithic lithium disilicate ceramic computer-aided design (CAD) after grinding. MATERIALS AND METHODS: This in vitro study was conducted on 52 partially crystalized bar-shaped specimens (16 × 4 × 1.6 mm) of monolithic lithium disilicate ceramic. The specimens were wet polished with 600-, 800-, and 1200-grit silicon carbide papers for 15 seconds using a grinding/polishing machine at a speed of 300 rpm. Then, the specimens were crystalized and glaze-fired in one step simultaneously and randomly divided into four groups of 13: (I) Glazing group (control); (II) Grinding-glazing group, subjected to grinding with red band finishing diamond bur (46 µm) followed by glazing; (III) Grinding-D+Z group, subjected to grinding and then polishing by coarse, medium, and fine diamond rubber points (D+Z); and (IV) Grinding-OptraFine group, subjected to grinding and then polishing with a two-step diamond rubber polishing system followed by a final polishing step with an OptraFine HP brush and diamond polishing paste. The surface roughness (Ra and Rz) values (µm) were measured by a profilometer, and the mean values were compared using one-way ANOVA and Tamhane's test (post hoc comparison). One specimen of each group was evaluated under a scanning electron microscope (SEM) for surface topography. The three-point flexural strength values of the bars were measured using a universal testing machine at a 0.5 mm/min crosshead speed and recorded. The data were analyzed using one-way ANOVA and Tamhane's test (α = 0.05). RESULTS: Statistically significant differences were noted among the experimental groups for Ra, Rz (p < 0.0001), and flexural strength values (p < 0.009). The lowest Ra and Rz values were found in the grinding-OptraFine group (0.465 ± 0.153), which were significantly lower than those in glazing (p < 0.03) and grinding-glazing (p < 0.001) groups. The Ra and Rz values were not significantly different between the two polishing systems (p = 0.23 and p = 0.25, respectively). The highest flexural strength was found in the glazing group (283.350 ± 49.854 MPa) without significant differences compared to grinding-glazing (p = 0.98) and grinding-OptraFine groups (p = 0.86). The lowest flexural strength was found in grinding-D+Z group (225.070 ± 17.299), which was significantly different from the value in glazing (p < 0.03) and grinding-glazing (p < 0.04) groups. SEM analysis of polished surfaces revealed regular morphology with some striations. CONCLUSIONS: The OptraFine system created smoother and more uniform surfaces in terms of quantity (p < 0.03 for Ra, p < 0.01 for Rz) and quality of roughness compared to glazing. The flexural strength of lithium disilicate ceramic after polishing with the OptraFine system was similar to that after glazing (p = 0.86). Despite similar surface roughness after polishing with the two systems, the D+Z system reduced the flexural strength of ceramic (p < 0.03).


Assuntos
Cerâmica/química , Polimento Dentário/métodos , Porcelana Dentária/química , Resistência à Flexão , Compostos Inorgânicos de Carbono , Desenho Assistido por Computador , Materiais Dentários/química , Polimento Dentário/instrumentação , Restauração Dentária Permanente , Diamante , Humanos , Técnicas In Vitro , Teste de Materiais , Ajuste Oclusal , Compostos de Silício , Estresse Mecânico , Propriedades de Superfície
14.
Anticancer Drugs ; 29(9): 847-853, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30157040

RESUMO

Targeting oncogenic signaling pathways by small molecules has emerged as a potential treatment strategy for cancer. reactivation of p53 and induction of tumor cell apoptosis (RITA) is a promising anticancer small molecule that reactivates p53 and induces exclusive apoptosis in tumor cells. Less well appreciated was the possible effect of small molecule RITA on p53-null leukemia cells. In this study, we demonstrated that RITA has potent antileukemic properties against p53-null chronic myeloid leukemia (CML)-derived K562 cells. RITA triggered apoptosis through caspase-9 and caspase-3 activation and poly (ADP-ribose) polymerase cleavage. RITA decreased STAT5 tyrosine phosphorylation, although it did not inhibit phosphorylation of the direct BCR-ABL substrate CrkL. Real-time PCR analysis showed that RITA downregulates antiapoptotic STAT5 target genes Bcl-xL and MCL-1. The downregulation of nuclear factor-κB (NF-κB), as evidenced by inhibition of IκB-α phosphorylation and its degradation, was associated with inhibition of Akt phosphorylation in RITA-treated cells. Furthermore, consistent with the decrease of mRNA levels, protein levels of the nuclear factor-κB-regulated antiapoptotic (cIAP1, XIAP, and Bcl-2) and proliferative (c-Myc) genes were downregulated by RITA in K562 cells. In conclusion, the ability of RITA to inhibit prosurvival signaling pathways in CML cells suggests a potential application of RITA in CML therapeutic protocols.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Furanos/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Regulação para Baixo/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
15.
J Musculoskelet Neuronal Interact ; 18(2): 200-207, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29855442

RESUMO

OBJECTIVES: This study investigated the benefits of regular recreational table tennis games for body composition, physical performance and muscle strength of older adult men. METHODS: We compared twenty older male regular table tennis players (RTTP) and twenty age- and weight-matched sedentary participants (SP). Body composition (LM, lean mass; FM, fat mass; BMD, bone mineral density), physical function, and muscle strength were analyzed with dual-energy X-ray absorptiometry, short physical performance battery (SPPB) and a hand-held dynamometer, respectively. RESULTS: The RTTP had a higher elbow flexor, knee extensor and plantar flexor muscle strength than the SP. The RTTP had a higher total, regional (arm, leg and lumbar spine), and site-specific (trochanter and Ward's triangle) BMD, and a lower fat mass, in total and regional terms (arm, leg, and truck) as well as percentage of body mass, than the SP. RTTP had a higher SPPB score and performed the 400-m walk in a shorter time than SP. CONCLUSIONS: These data suggest that regular table tennis has beneficial effects on muscle strength, physical performance and body composition, and is a potent activity to improve health in older adults.


Assuntos
Envelhecimento/fisiologia , Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Força Muscular/fisiologia , Aptidão Física/fisiologia , Esportes/fisiologia , Absorciometria de Fóton , Idoso , Estudos Transversais , Teste de Esforço , Nível de Saúde , Humanos , Masculino , Músculo Esquelético/fisiologia , Comportamento Sedentário , Caminhada/fisiologia
16.
Sci Eng Ethics ; 24(2): 779-784, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28397173

RESUMO

The main objective of the present paper is to introduce some features of fake/bogus conferences and some viable approaches to differentiate them from the real ones. These fake/bogus conferences introduce themselves as international conferences, which are multidisciplinary and indexed in major scientific digital libraries. Furthermore, most of the fake/bogus conference holders offer publishing the accepted papers in ISI journals and use other techniques in their advertisement e-mails.


Assuntos
Pesquisa Biomédica , Congressos como Assunto , Enganação , Fraude/prevenção & controle , Correio Eletrônico , Humanos , Editoração
17.
J Prosthet Dent ; 118(5): 658-665, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28385438

RESUMO

STATEMENT OF PROBLEM: Limited information is available for the best polishing systems and methods to obtain minimally abrasive monolithic zirconia surfaces after contouring and occlusal adjustment. PURPOSE: The purpose of this in vitro study was to evaluate the effect of grinding and polishing procedures on the flexural strength, quality and quantity of surface roughness, topography, and phase transformation of a zirconia-based ceramic system. MATERIAL AND METHODS: Fifty bar-shaped yttrium-stabilized zirconium oxide specimens (20×4×2 mm) were cut from presintered zirconia blanks. The specimens were wet-polished and divided into 5 groups (n=10): standard polishing without any surface treatment (group SP); grinding with a diamond rotary instrument (group Gr); grinding with a diamond rotary instrument (DRI) and over-glazing (group Gl); grinding with a DRI and polishing with an intraoral zirconia polishing kit in a 2-step procedure (group BP); and grinding with a DRI and polishing with an intraoral polishing kit (group MP). The Ra and Rz surface roughness values (µm) were measured with a profilometer. One specimen of each group was subjected to x-ray diffraction (XRD) to estimate the monoclinic phase and evaluated using scanning electron microscopy (SEM) for surface topography. The 3-point flexural strength of the bars was measured in a universal testing machine at a crosshead speed of 0.5 mm/min. The mean flexural strength (MPa) and surface roughness values were calculated, and the results were analyzed using 1-way ANOVA and Tukey honest significant difference tests (α=.05). RESULTS: Statistically significant differences were noted among the experimental groups for Ra, Rz (P<.001), and flexural strength values (P<.001). The highest Ra and Rz values were found in group Gr (P<.001) and the lowest in group Gl, which were significantly lower than the values in group Gr (P<.001). The 2 polishing systems (BP and MP) were not significantly different in terms of Ra and Rz values (P=.755 for Ra and P=.319 for Rz). The highest flexural strength was found in group Gr (283.35 ±49.85 MPa) without significant differences from those of MP and BP (P=.958 for BP and P=.404 for MP). The lowest flexural strength was found in Gl, which had no significant differences from those of the control group (P=1.000). In XRD the monoclinic phase was observed in Gr (26%), BP (24%), and MP (23%) groups. However, groups Gl and SP did not have any monoclinic phase. SEM showed deep unidirectional scratches after grinding that were smoothened by glazing and polishing. CONCLUSIONS: Roughness increased significantly after grinding, but polishing and glazing similarly diminished it. Glazing after grinding significantly decreased the flexural strength values, but polishing did not.


Assuntos
Cerâmica/uso terapêutico , Prótese Dentária , Ítrio/uso terapêutico , Zircônio/uso terapêutico , Polimento Dentário , Humanos , Técnicas In Vitro , Propriedades de Superfície , Resistência à Tração
18.
Water Sci Technol ; 75(10): 2381-2389, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28541946

RESUMO

In this paper, cobalt ferrite magnetic nanoparticle was modified by N-(2-aminoethyl)-3-(trimethoxysilyl) propyl amine. Polyoxometalate was immobilized on the modified bi-amino surface functionalized nanoparticle to prepare the environmentally friendly catalyst nanoparticle (EFCN). The synthesized EFCN was characterized using Fourier transform infrared, scanning electron microscopy and X-ray powder diffraction. The EFCN was used for photocatalytic dye degradation. Acid Red 18 and Direct Red 81 were used as model dyes. The effect of catalyst dosage, dye concentration and salt on dye degradation was studied. Dye degradation increases by catalyst dosage. The results showed that decolorization followed a zero-order kinetic model.


Assuntos
Corantes/química , Modelos Químicos , Nanocompostos/química , Compostos de Tungstênio/química , Catálise , Corantes/análise
19.
Tumour Biol ; 37(10): 14117-14128, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27517565

RESUMO

Imatinib mesylate (IM) is a frontline treatment in the early chronic phase of chronic myeloid leukemia (CML). However, intrinsic and acquired resistance against this drug has been defined and this issue has become a problem and a challenge in CML treatment. According to new findings, the inhibition of Janus kinase 2 (Jak2) in Bcr-Abl+ cells can promote apoptosis in IM-resistant cells. microRNAs (miRNAs) regulate the gene expression by targeting the messenger RNA (mRNA) for degradation. Recently, a growing body of evidence has implicated that dysregulation of miRNAs is associated with cancer initiation and development. In this report, we proposed that miRNA-101 targets Jak2 mRNA and regulates its expression and induces K562 leukemia cell apoptosis. Here, we transduced the K562 cell line with a miR-101-overexpressing vector and evaluated the Jak2 mRNA level. Our results showed that miR-101 overexpression in Bcr-Abl+ cells reduced the Jak2 mRNA level. Moreover, imatinib treatment and miR-101 upregulation led to miR-23a overexpression, which has putative binding site(s) on 3'-untranslated regions (3'-UTRs) of STAT5, CCND1, and Bcl-2 genes. Our results also indicated that miR-101 overexpression inhibited cell proliferation indicated by the MTT assay and promoted apoptosis detected via flow cytometry. Importantly, mRNA expression of NF-kappa B-regulated anti-apoptotic (Bcl-2, Bcl-xl, MCL-1, XIAP, and survivin) and proliferative (c-Myc and CCND1) genes was decreased. These findings suggest that miR-101 acts as a tumor suppressor by downregulating Jak2 expression and sensitizing K562 cells to imatinib. Therefore, restoration of miR-101 may be a therapeutic approach for CML treatment.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Mesilato de Imatinib/farmacologia , Janus Quinase 2/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , MicroRNAs/genética , NF-kappa B/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/genética , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , NF-kappa B/genética , NF-kappa B/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
20.
J Contemp Dent Pract ; 17(8): 635-8, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27659079

RESUMO

INTRODUCTION: Since one of the most important disadvantages of soft drinks includes their adverse effect on mineral content of enamel because of their low pH, this study examined the microhardness of enamel before and after exposure to a soft drink containing different concentrations of nano-hydroxyapatite (nano-HA) as an additive. MATERIALS AND METHODS: Sixty caries free human premolars were mounted in epoxy resin. After polishing, the baseline micro-hardness was recorded three times for each specimen using a Vickers indenter at 50 gm load. Subsequently, the samples were divided into six groups, which were treated for 5 minutes at 9°C by a cola-based drink contacting 0, 0.5, 1, 5, and 10 wt.% of nano-HA while the control group was immersed in artificial saliva. Ultimately, the final microhardness was assessed three times again for each specimen. RESULTS: Paired t-test showed that in groups containing 0 and 0.5 wt.% of nano-HA, the microhardness was significantly reduced after treatment protocol (p = 0.00 and 0.01 respectively). Whereas in the other groups the microhardness was not significantly changed after treatment (p > 0.05). CONCLUSION: Pure cola-based drink has a pronounced adverse effect on enamel microhardness, while admixing it with nano-HA could act as a protective factor. CLINICAL SIGNIFICANCE: Although soft beverages are hazardous to tooth structure, some additives could compensate their adverse effect.


Assuntos
Bebidas Gaseificadas/efeitos adversos , Durapatita/administração & dosagem , Nanoestruturas/administração & dosagem , Erosão Dentária/prevenção & controle , Esmalte Dentário/efeitos dos fármacos , Dureza , Humanos , Concentração de Íons de Hidrogênio , Erosão Dentária/etiologia
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