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1.
Braz. j. med. biol. res ; 55: e12252, 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1403899

RESUMO

Nanosized copper particles (nano Cu) have been incorporated into products in multiple industries, although studies have demonstrated that these particles are nephrotoxic. We investigated the cytotoxicity of nanosized copper particles on rat mesangial cells and measured rates of apoptosis, the expression of caspase-3, and generation of reactive oxygen species. We also measured autophagy through the acridine orange (AO) staining and expression of Beclin-1, microtubule-associated protein 1 light chain 3, and p62 to screen the underlying mechanism of toxicity. Nanosized copper particles inhibited mesangial cell viability, up-regulated the activity of caspase-3, and increased the rates of apoptosis and the generation of reactive oxygen species in a concentration-dependent manner. Exposure to nano Cu increased the formation of acidic vesicular organelles and the expression of Beclin-1, microtubule-associated protein 1 light chain 3, and p62, and treatment with an autophagy inhibitor reduced nephrotoxicity. This indicated that the autophagy pathway is involved in the toxicity induced by nanosized copper particles to mesangial cells. This finding can contribute to the development of safety guidelines for the evaluation of nanomaterials in the future.

2.
Electron. j. biotechnol ; 54: 1-7, nov.2021. graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1510684

RESUMO

BACKGROUND Synthesis of selenium nanoparticles from selenite by Shewanella sp. HN-41 demonstrated that particle size depended on the reaction time and biomass of cells. The slow reaction and low biomass tended to form small particles. In this study, Shewanella sp. HN-41 was introduced into the anode of a nonexternal circuit bioelectrochemical system (nec_BES) to convert chemical energy from lactate to low electron current to the cathode, where selenite was reduced. RESULTS Our experiment with two systems, one bioelectrochemical system with a cathode flushed with nitrogen and the other with a no-nitrogen-flushing cathode, showed that the former could not produce Se nanoparticles after 21 d, but the latter formed them with an average size of 37.7 nm. The SEM and TEM images demonstrated that the particle size of 10 nm occupied over 10% and most of the particles were in the range of 30­60 nm. The XRD result and SAED image demonstrated no clear peaks of crystal and proved that the Se nanoparticles are amorphous. CONCLUSIONS : The clean Se nanoparticles were synthesized and completely separated from bacterial cells in the bioelectrochemical system. This study opened a new approach for the biological synthesis of metal nanoparticles. Finally, the Se products in the range of 30­60 nm can be tested for antimicrobial activities in medical applications


Assuntos
Selênio/química , Shewanella/metabolismo , Selênio/metabolismo , Shewanella/genética , Eletrodos , Nanopartículas/química , Técnicas Eletroquímicas
3.
Acta Pharmaceutica Sinica ; (12): 3212-3223, 2021.
Artigo em Chinês | WPRIM | ID: wpr-906817

RESUMO

Natural polysaccharides with good biocompatibility and unique tumor immunomodulatory activity are becoming an important adjuvant anticancer therapy in clinic. In the field of pharmaceutics, natural polysaccharides can be used as not only bioactive components but also drug delivery carriers, as well as tumor-targeted ligands. Besides, various novel drug delivery systems based on natural polysaccharides exhibit unique advantages in regulating tumor immune microenvironment. In this review, we summarize the progress on natural polysaccharides in tumor microenvironment (TME) regulation and the designs of nano-sized drug delivery system, and point out challenges of polysaccharide-based drug delivery systems in the future application, and also give the potential solutions for these issues.

4.
Acta Pharmaceutica Sinica ; (12): 1802-1809, 2019.
Artigo em Chinês | WPRIM | ID: wpr-780306

RESUMO

Immunotherapy has emerged as one of the major modalities for clinical cancer therapy, along with surgery, chemotherapy, radiotherapy and targeted therapy. However, tumor-targeted delivery of immune therapeutics is challenged by a series of barriers including non-specific release, poor tumor penetration capacity, and insufficient cellular uptake of the therapeutic regimens, which seriously restricted the efficiency and efficacy of immunotherapy. To address above challenges, nanosized drug delivery systems (NDDS) have been extensively exploited to achieve tumor-targeted delivery of immunotherapy drugs. It has been well investigated that solid tumors are of unique characteristics including acidic, hypoxic and enzymatic extracellular microenvironment. Meanwhile, the tumor cells are of acidic, reductant and reactive oxygen species intracellular microenvironment. In recent years, a large variety of tumor microenvironment-activatable NDDS have been exploited to respond specifically to the stimulus of extracellular or intracellular tumor microenvironment for enhancing the accumulation, retention and penetration in the tumor tissue. These NDDS were also employed to promote intracellular uptake and tunable drug release inside the tumor cells. In this review article, we summarized the recent progress of our laboratory using the tumor microenvironment-activatable NDDS for immune efficient therapeutics delivery, and improved cancer immunotherapy. We also briefly discussed the challenges and provided perspective of NDDS-based cancer immunotherapy.

5.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 81-89, 2019.
Artigo em Chinês | WPRIM | ID: wpr-804679

RESUMO

Objective@#To explore the correlation between expression level of miRNAs and pulmonary fibrosis on the basis of comparison the differential expression of miRNAs in rat pulmonary fibrosis induced by nano SiO2 and micron SiO2.@*Methods@#Thirty-six healthy male SD rats weighting 180-220 g were randomly divided into 3 groups. They were instilled intratracheally with 1 ml suspension of saline, 25 mg/ml nanosized SiO2 and microsized SiO2 particles and sacrificed at 60 d and 90 d postexposure from each group with six rats. The change of pathological morphology and ultrastructure of lung were observed by optical and transmission electron microscopy. The differentially expressed microRNAs in lung tissue of the rats after instilled intrachcally nanosized SiO2 and microsized SiO2 particles at 60 d and 90 d were determined by Illumina HiSeq 2 000 sequencing technique. Target prediction for miRNAs was conducted by databases of Target-scan. Function-significant enrichment analysis and signal pathway analysis for predicted target genes were respectively conducted by the GO and the KEGG, then target genes related to pulmonary fibrosis were screened out.@*Results@#Light microscope examination showed that wide bronchi, vessels, interlobular septa and slight fibrous connective tissue proliferation at 60 d and 90 d postexposure in 25 mg/ml nanosized SiO2 group. A few fused nodules at 30 d postexposure, a lot of fused nodules at 60 d postexposure, fibrous cell nodules and compensatory emphysema around alveolar at 90 d postexposure in 25 mg/mL microsized SiO2 group were observed. Electron microscopy demonstrated swelling and vacuolar degeneration of osmiophilic lamellar bodies in type Ⅱ alveolar epithelial cells, collagen fiber and elastic fiber hyperplasia in pulmonary interstitial at 60 d, 90 d postexposure in 25 mg/ml nanosized SiO2 group. Increased and vacuoloid changed osmiophilic lamellar bodies in type Ⅱ alveolar epithelial cells, collagen fiber and elastic fiber hyperplasia in the interstitial at 60 d, 90 d postexposure in 25 mg/ml microsized SiO2 group were observed. Comparing to saline control group, the number of miRNA up-regulated expression was 50, 70, and down-regulated expression was 22 and 24 at 60 d, 90 d postexposure in 25 mg/ml nanosized SiO2 group respectively. There were 91,70 miRNAs up-regulated expression and 34,78 miRNAs down-regulated expression at 60 d, 90 d postexposure in 25 mg/ml microscale SiO2 group. The common miRNA of differential up-regulated expression are miRNA-18a and miRNA-702-3p, down-regulated expression are miRNA-541, miRNA-127 and miRNA-379 both in nanosized SiO2 and microscale SiO2 group. The target genes related to pulmonary fibrosis were CTGF, IGF, BMP7, FGF7, TGF-β RIII, IGF1R and TGF-β1 respectively. Their biologic functions are to regulate signal pathway of TGF-β, MAPK and Wnt, and activation of fibroblast.@*Conclusion@#These findings suggested that same dose of nanosized SiO2 particles could cause mainly characterized by pulmonary interstitial fibrosis differing from silicotic nodule caused by microsized SiO2. miRNA-18a, miRNA-702-3p, miRNA-541, miRNA-127 and miRNA-379 may play a role in the process of pulmonary fibrosis in nanosized SiO2 and microscale SiO2 by regulating its target genes.

6.
Braz. J. Pharm. Sci. (Online) ; 54(3): e17382, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974400

RESUMO

Effective management of schizophrenia, acute mania, mixed episodes associated with bipolar disorders, and depression can be managed with aripiprazole moiety. In the present research work an attempt was made to minimize the dose related side effects thus improving the quality life of the patients. A novel biopolymer was isolated from the fruits of Trachyspermum ammi. Ten optimized nanosized aripiprazole loaded formulations were prepared in 1-5% concentration of biopolymer (FA1-FA5) and sodium CMC (FM1-FM5) by solvent casting technique. The formulated flexy films were evaluated for thickness, folding endurance, weight uniformity, surface pH, mucoadhesivity, In-vitro drug release studies, In-vivo pharmacodynamic study and stability studies. The isolated biopolymer showed inbuilt fimability and mucoadhesivity and consists of carbonyl, hydroxyl and thiocarbonyl functional groups. All formulations showed folding endurance from 153 to 170, mucoadhesion time in the range of 24-48hrs., and in-vitro drug release was performed using dynamic Franz Diffusion cell and analyzed using BIT-SOFTWARE. The experimental animals showed improved activity score on actophotometer. The formulated nanosized aripiprazole loaded bio-flexy films showed pharmacotherapeutic response. Conclusion can be drawn that optimized formulation showed effective Pharmacodynamic activity and can be used as for improving therapeutic efficacy of aripiprazole through this platform.


Assuntos
Esquizofrenia/diagnóstico , Aripiprazol/efeitos adversos , Mucosa Bucal , Palato Mole , Biopolímeros/agonistas , Técnicas In Vitro/instrumentação , Carum/efeitos adversos
7.
Araçatuba; s.n; 2018. 107 p. ilus, graf, tab.
Tese em Inglês, Português | LILACS, BBO | ID: biblio-914523

RESUMO

O objetivo geral deste estudo foi avaliar o efeito de um dentifrício fluoretado convencional (1100 ppm F), contendo nanopartículas de hexametafosfato de sódio (HMPnano) sobre a remineralização de lesões artificiais de cárie e desmineralização do esmalte in situ e biofilme. O estudo de remineralização, foi duplo-cego cruzado, realizado em quatro fases de três dias cada. Voluntários (n=12) usaram dispositivos palatinos contendo quatro blocos de esmalte bovino com lesões artificiais de cárie. A seguir foram distribuídos aleatoriamente nos seguintes grupos de tratamento: sem F/HMP/HMPnano (Placebo); 1100 ppm F (1100F); 1100F associado a 0,5% HMP microparticulado e nanoparticulado (1100F/HMP; 1100F/HMPnano). Os voluntários foram instruídos a escovar seus dentes naturais com os dispositivos palatinos na boca durante 1 min (3x/dia), de modo que os blocos foram tratados com slurry de dentifrícios. Após cada fase, determinou-se a porcentagem de recuperação de dureza de superfície (%SHR), recuperação integrada de dureza de subsuperfície (ΔIHR), recuperação mineral integrada (ΔIMR) e concentração de fluoreto (F) no esmalte. Os resultados foram submetidos a análise de variância de medidas repetidas seguido pelo teste Student-Newman-Keuls (p < 0,001). A superfície do esmalte tornou-se 68% mais remineralizada quando tratada com 1100F/HMPnano em comparação com 1100F (p < 0,001). O tratamento com 1100F/HMP e 1100F/HMPnano promoveu um aumento em ~ 23% e ~ 87% da ΔIHR quando comparado ao 1100F (p < 0,001). Além disso, ΔIMR foi de ~ 75% e ~ 33% maior para 1100F/HMPnano quando comparado a 1100F e 1100F/HMP, respectivamente (p < 0,001). O estudo de desmineralização foi duplo-cego cruzado, e consistiu em quatro fases (7 dias cada). Voluntários (n=12) usaram aparelhos palatinos contendo quatro blocos de esmaltes bovinos. O desafio cariogênico foi realizado pela solução de sacarose a 30% (6x/dia). Os tratamentos com os dentífricios (3x/dia) foram os seguintes: sem F/ HMP/HMPnano (Placebo); 1100 ppm F (1100F); 1100F associado a 0,5% HMP microparticulado e nanoparticulado (1100F/HMP; 1100F/HMPnano). Após sete dias determinou-se a porcentagem de perda de dureza de superfície (%SH), perda integrada de dureza subsuperfície (ΔKHN), cálcio (Ca), fósforo (P) e fluoreto (F) no esmalte. Além disso, no biofilme formado sobre os blocos analisou-se as concentrações de polissacarídeos extracelulares (EPS), F, Ca, P. Os resultados foram submetidos a análise de variância de medidas repetidas seguido pelo teste Student-Newman-Keuls (p < 0,001). Resultados: 1100F/HMPnano promoveu menor %SH e ΔKHN quando comparado aos demais grupos (p < 0,001). A adição de HMPnano a 1100F não aumentou a absorção de F e P no esmalte, mas aumentou significativamente as concentrações de Ca (p < 0,001). O grupo 1100F/HMPnano apresentou valores mais baixos de concentração de EPS quando comparado com 1100F (~ 70%) (p < 0,001). Todos os grupos foram supersaturados em relação a hidroxiapatita (HA). Somente, o grupo 1100F/HMPnano foi supersaturado em relação ao fluoreto de cálcio (CaF2) (p < 0,05). As atividades iônicas de íon fluoreto de cálcio (CaF+) e fluoreto de hidrogênio neutro (HF0) para o grupo 1100F/HMPnano foram significativamente maiores quando comparadas aos demais grupos (p < 0,001). Conclui-se que a adição de HMPnano a um dentifrício convencional promoveu um efeito remineralizador significantemente maior em lesões artificiais de cárie e demonstrou um maior efeito protetor contra a desmineralização e variáveis do biofilme in situ(AU)


The aim of this study was to evaluate the effect of a conventional fluoride toothpaste (1100 ppm F) containing nano-sizeds of sodium hexametaphosphate (HMPnano) on the remineralization of artificial caries lesions and enamel demineralization and biofilm in situ. The remineralization study was double-blinded crossed, performed in 4 phases of 3 days each. Volunteers (n = 12) used palatal devices containing four blocks of bovine enamel with artificial lesions of caries. They were then randomly assigned to the following treatment groups: without F/ HMP/HMPnano (Placebo); 1100 ppm F (1100F); 1100F associated with 0.5% HMP microparticulate and nano-sized (1100F/HMP; 1100F/ HMPnano). The volunteers were instructed to brush their natural teeth with the palatine devices in the mouth for 1 min (3x/day), so that the blocks were treated with slurry of toothpastes. After each phase, the percentage of surface hardness recovery (%SHR), integrated recovery of subsurface hardness (ΔIHR), integrated mineral recovery (ΔIMR) and fluoride (F) concentration in the enamel were determined. The results were subjected to analysis of variance of repeated measures followed by Student-Newman-Keuls test (p < 0.001). The enamel surface became 68% more remineralized when treated with 1100F/ HMPnano compared to 1100F (p < 0.001). Treatment with 1100F/HMP and 1100F/ HMPnano promoted an increase in ~ 23% and ~ 87% of ΔIHR when compared to 1100F (p < 0.001). In addition, ΔIMR was ~ 75% and ~ 33% higher for 1100F/HMPnano when compared to 1100F and 1100F/HMP, respectively (p < 0.001). The study of demineralization was double-blinded crossed, and consisted of four phases (7 days each). Volunteers (n = 12) used palatal appliances containing four blocks of bovine enamel. The cariogenic challenge was accomplished by the solution of sucrose 30% (6x/day). Treatments with the toothpaste (3x/day) were as follows: without F/HMP/HMPnano (Placebo); 1100 ppm F (1100F); 1100F associated with 0.5% HMP microparticulate and nano-sized (1100F/HMP; 1100F/HMPnano). After 7 days the percentage of surface hardness loss (%SH), integrated loss of subsurface hardness (ΔKHN), calcium (Ca), phosphorus (P) and fluoride (F) in the enamel were determined. The results were submitted to analysis of variance of repeated measurements followed by the Student-Newman-Keuls test (p < 0.001). The results were analyzed using the Student-Newman-Keuls test (p < 0.001). Results: 1100F/HMPnano promoted lower %SH and ΔKHN when compared to the other groups (p < 0.001). Addition of HMPnano to 1100F did not increase the absorption of enamel F, but significantly increased enamel Ca concentrations (p < 0.001). The 1100F/HMPnano group had lower values of EPS concentration when compared to 1100F (~ 70%) (p < 0.001). All groups were supersaturated with respect to hydroxyapatite (HA). Only, the 1100F/HMPnano group was supersaturated relative to calcium fluoride (CaF2) (p < 0.05). The ionic activities of calcium fluoride ion (CaF+) and neutral hydrogen fluoride (HF0) for the 1100F/HMPnano group were significantly higher when compared to the other groups (p < 0.001). It was concluded that the addition of HMPnano to a conventional toothpaste promoted a significantly greater remineralizing effect on artificial caries lesions and demonstrated a greater protective effect against demineralization and biofilm in situ(AU)


Assuntos
Humanos , Masculino , Feminino , Esmalte Dentário , Flúor , Fosfatos , Placa Dentária , Dentifrícios , Nanopartículas , Desmineralização do Dente , Remineralização Dentária
8.
Acta Pharmaceutica Sinica ; (12): 375-382, 2018.
Artigo em Chinês | WPRIM | ID: wpr-779885

RESUMO

Extracellular acidity has been associated with many pathological states, such as cancer, ischemic stroke, neurotrauma and infection, which makes it an effective target for therapy and diagnosis of such diseases. As a polypeptide vector, pH low insertion peptides (pHLIPs) are endowed with high sensitivity to extracellular acidic environment, which can insert the membrane and deliver payload to pathological cells in a pH dependent manner. Here, theranostic applications of pHLIP in disease, are reviewed in two aspects:pHLIP-mediated single-molecule transporter and nano-sized carrier.

9.
Journal of Pharmaceutical Practice ; (6): 103-105, 2016.
Artigo em Chinês | WPRIM | ID: wpr-790568

RESUMO

Multidrug resistance (MDR) of tumor cell is the major problem for chemotherapy.However,there is no ef-fective strategy to overcome MDR due to the complicated mechanism.The nano-sized drug delivery system could target to the tumor cell.Moreover,it could delivery different kinds of drugs.Therefore,the nano-sized drug delivery system has become a promising approach to reverse MDR.The nano-sized drug delivery system which is applied to treat the MDR of tumor (osteo-sarcoma) was summarized and the reverse mechanism was discussed.

10.
Korean Journal of Veterinary Research ; : 133-139, 2015.
Artigo em Inglês | WPRIM | ID: wpr-114942

RESUMO

The increasing uses of zinc oxide nanoparticles (nZnO) in industrial and personal care products raise possible danger of using nZnO in human. To determine whether ZnO induces size-dependent anomalies during embryonic organogenesis, mouse embryos on embryonic day 8.5 were cultured for 2 days under 50, 100, and 150 microg of nZnO (< 100 nm) or micro-sized ZnO (mZnO; 80 +/- 25 microm), after which the morphological changes, cumulative quantity of Zn particles, and expressions of antioxidant and apoptotic genes were investigated. Although embryos exposed to 50 microg of ZnO exhibited no defects on organogenesis, embryos exposed to over 100 microg of ZnO showed increasing anomalies. Embryos treated with 150 microg of nZnO revealed significant changes in Zn absorption level and morphological parameters including yolk sac diameter, head length, flexion, hindbrain, forebrain, branchial bars, maxillary process, mandibular process, forelimb, and total score compared to the same dose of mZnO-treated embryos. Furthermore, CuZn-superoxide dismutase, cytoplasmic glutathione peroxidase (GPx) and phospholipid hydroperoxidase GPx mRNA levels were significantly decreased, but caspase-3 mRNA level was greatly increased in nZnO-treated embryos as compared to normal control embryos. These findings indicate that nZnO has severer teratogenic effects than mZnO in developing embryos.


Assuntos
Animais , Humanos , Camundongos , Absorção , Caspase 3 , Citoplasma , Estruturas Embrionárias , Membro Anterior , Glutationa Peroxidase , Cabeça , Nanopartículas , Organogênese , Prosencéfalo , Rombencéfalo , RNA Mensageiro , Teratogênese , Saco Vitelino , Óxido de Zinco
11.
Araçatuba; s.n; 2014. 159 p. tab, ilus, graf.
Tese em Inglês, Português | LILACS | ID: lil-756117

RESUMO

O objetivo deste estudo foi avaliar a capacidade de dentifrícios convencionais (1100 ppm F) suplementados com trimetafosfato de sódio micrométrico ou nanoparticulado (TMP; TMPnano), em reduzir a desmineralização (in vitro), promover a remineralização (in situ) e reduzir a erosão dentária (in vitro). No estudo de desmineralização, blocos de esmalte bovino (n = 96) selecionados pela dureza de superfície inicial (SHi) foram divididos em oito grupos de dentifrícios (n = 12): sem fluoreto e sem TMP (Placebo); 1100 ppm F (1100 ppm F); 1100 ppm F associado 1% TMP micrométrico e nanoparticulado (1100 1%TMP; 1100 1%TMPnano), 1100 ppm F associado a 3% TMP micrométrico e nanoparticulado (1100 3%TMP; 1100 3%TMPnano), 1110 ppm F associado a 6% TMP micrométrico e nanoparticulado (1100 6%TMP; 1100 6%TMPnano). Os blocos foram submetidos a ciclagem de pH durante cinco dias, sendo o tratamento com os respectivos dentifrícios realizados 2x/dia. A seguir, determinou-se a dureza de superfície final (SHf), perda mineral integrada (IML), diferencial da perda mineral integrada (ΔIML) e fluoreto (F) no esmalte. Os resultados foram submetidos à análise de variância seguida pelo teste Student-Newman-Keuls (p < 0,001). O grupo 1100 3%TMPnano apresentou a menor perda mineral (SHf, IML e ΔIML) seguido pelo grupo 1100 3%TMP (p < 0,001). O grupo 1100 3%TMPnano apresentou a maior concentração de F no esmalte, seguido pelo 1100 6%TMPnano (p < 0,001). Para o estudo de remineralização, blocos de esmalte bovinos (n = 192) foram selecionados pela dureza de superfície pós-desmineralização (SH1), e divididos em quatro grupos experimentais: Placebo, 1100 ppm F, 1100 3% TMP micrométrico (1100 TMP), 1100 3% TMP nanoparticulado (1100 TMPnano). Doze voluntários utilizaram dispositivos palatinos, com quatro blocos de esmalte desmineralizados, durante três dias, sendo a escovação realizada 3x/dia. Após o período de remineralização determinou-se a porcentagem de recuperação de dureza de superfície (%SHR)...


The aim of this study was to evaluate the ability of conventional toothpaste (1100 ppm F) supplemented with micrometric or nano-sized sodium trimetaphosphate (TMP; TMPnano ), in reducing demineralization (in vitro), promote remineralization ( in situ ) and reduce erosion tooth (in vitro). In the study of demineralization of bovine enamel blocks (n = 96 ) selected by the initial surface hardness ( SHi ) were divided into eight groups of toothpaste (n = 12) without fluoride and without TMP (Placebo), 1100 ppm F (1100 ppm F) 1100 ppm F associated 1% TMP micrometric and nano-sized (1100 1%TMP; 1100 1%TMPnano), 1100 ppm F associated with 3% TMP micrometric and nano-sized (1100 3%TMP; 1100 3%TMPnano), 1110 ppm F associated with 6% TMP micrometric and nano-sized TMP (1100 6%TMP; 1100 6%TMPnano). The blocks were subjected to pH cycling for five days, and treatment with their toothpastes made 2x/day. Next, we determined the final surface hardness (SHf), integrated mineral loss (IML), differential integrated mineral loss (ΔIML) and fluoride (F) in the enamel. The results were subjected to analysis of variance followed by Student-Newman-Keuls test (p < 0.001). The group 1100 3 %TMPnano had the lowest mineral loss (SHF, IML and ΔIML) followed by 1100 3%TMP group (p < 0.001). The group 100 3%TMPnano showed a higher concentration of F in the enamel, followed by 1100 6%TMPnano (p < 0.001). For the study of remineralization of bovine enamel blocks (n = 192) were selected by the hardness of the surface after demineralization (SH1), and divided into four groups: Placebo, 1100 ppm F, 1100 3 % TMP micrometric (1100 TMP) and 1100 3% TMP nano-sized (1100 TMPnano ). Twelve volunteers wore palatal appliances with four blocks of demineralized enamel, for three days, and brushing held 3x/day. After the period of remineralization determined the percentage of recovery of surface hardness (%SHR), recovery of integrated mineral loss (IMLR), and F ΔIML enamel. The %SHR, ΔIML and F were...


Assuntos
Humanos , Masculino , Feminino , Adulto , Esmalte Dentário , Dentifrícios , Flúor , Nanopartículas , Fosfatos , Desmineralização do Dente , Erosão Dentária , Remineralização Dentária
12.
Araçatuba; s.n; 2014. 159 p. tab, ilus, graf.
Tese em Inglês, Português | LILACS, BBO | ID: biblio-867179

RESUMO

O objetivo deste estudo foi avaliar a capacidade de dentifrícios convencionais (1100 ppm F) suplementados com trimetafosfato de sódio micrométrico ou nanoparticulado (TMP; TMPnano), em reduzir a desmineralização (in vitro), promover a remineralização (in situ) e reduzir a erosão dentária (in vitro). No estudo de desmineralização, blocos de esmalte bovino (n = 96) selecionados pela dureza de superfície inicial (SHi) foram divididos em oito grupos de dentifrícios (n = 12): sem fluoreto e sem TMP (Placebo); 1100 ppm F (1100 ppm F); 1100 ppm F associado 1% TMP micrométrico e nanoparticulado (1100 1%TMP; 1100 1%TMPnano), 1100 ppm F associado a 3% TMP micrométrico e nanoparticulado (1100 3%TMP; 1100 3%TMPnano), 1110 ppm F associado a 6% TMP micrométrico e nanoparticulado (1100 6%TMP; 1100 6%TMPnano). Os blocos foram submetidos a ciclagem de pH durante cinco dias, sendo o tratamento com os respectivos dentifrícios realizados 2x/dia. A seguir, determinou-se a dureza de superfície final (SHf), perda mineral integrada (IML), diferencial da perda mineral integrada (ΔIML) e fluoreto (F) no esmalte. Os resultados foram submetidos à análise de variância seguida pelo teste Student-Newman-Keuls (p < 0,001). O grupo 1100 3%TMPnano apresentou a menor perda mineral (SHf, IML e ΔIML) seguido pelo grupo 1100 3%TMP (p < 0,001). O grupo 1100 3%TMPnano apresentou a maior concentração de F no esmalte, seguido pelo 1100 6%TMPnano (p < 0,001). Para o estudo de remineralização, blocos de esmalte bovinos (n = 192) foram selecionados pela dureza de superfície pós-desmineralização (SH1), e divididos em quatro grupos experimentais: Placebo, 1100 ppm F, 1100 3% TMP micrométrico (1100 TMP), 1100 3% TMP nanoparticulado (1100 TMPnano). Doze voluntários utilizaram dispositivos palatinos, com quatro blocos de esmalte desmineralizados, durante três dias, sendo a escovação realizada 3x/dia. Após o período de remineralização determinou-se a porcentagem de recuperação de dureza de superfície (%SHR)...


The aim of this study was to evaluate the ability of conventional toothpaste (1100 ppm F) supplemented with micrometric or nano-sized sodium trimetaphosphate (TMP; TMPnano ), in reducing demineralization (in vitro), promote remineralization ( in situ ) and reduce erosion tooth (in vitro). In the study of demineralization of bovine enamel blocks (n = 96 ) selected by the initial surface hardness ( SHi ) were divided into eight groups of toothpaste (n = 12) without fluoride and without TMP (Placebo), 1100 ppm F (1100 ppm F) 1100 ppm F associated 1% TMP micrometric and nano-sized (1100 1%TMP; 1100 1%TMPnano), 1100 ppm F associated with 3% TMP micrometric and nano-sized (1100 3%TMP; 1100 3%TMPnano), 1110 ppm F associated with 6% TMP micrometric and nano-sized TMP (1100 6%TMP; 1100 6%TMPnano). The blocks were subjected to pH cycling for five days, and treatment with their toothpastes made 2x/day. Next, we determined the final surface hardness (SHf), integrated mineral loss (IML), differential integrated mineral loss (ΔIML) and fluoride (F) in the enamel. The results were subjected to analysis of variance followed by Student-Newman-Keuls test (p < 0.001). The group 1100 3 %TMPnano had the lowest mineral loss (SHF, IML and ΔIML) followed by 1100 3%TMP group (p < 0.001). The group 100 3%TMPnano showed a higher concentration of F in the enamel, followed by 1100 6%TMPnano (p < 0.001). For the study of remineralization of bovine enamel blocks (n = 192) were selected by the hardness of the surface after demineralization (SH1), and divided into four groups: Placebo, 1100 ppm F, 1100 3 % TMP micrometric (1100 TMP) and 1100 3% TMP nano-sized (1100 TMPnano ). Twelve volunteers wore palatal appliances with four blocks of demineralized enamel, for three days, and brushing held 3x/day. After the period of remineralization determined the percentage of recovery of surface hardness (%SHR), recovery of integrated mineral loss (IMLR), and F ΔIML enamel. The %SHR, ΔIML and F were...


Assuntos
Humanos , Masculino , Feminino , Adulto , Esmalte Dentário , Dentifrícios , Flúor , Nanopartículas , Fosfatos , Desmineralização do Dente , Erosão Dentária , Remineralização Dentária
13.
Artigo em Inglês | IMSEAR | ID: sea-162300

RESUMO

Aims: The goal of the study was to evaluate concentrations of nanosized TiO2 at 0, 5, 20, 40, 60 and 80 mg L-1 with same concentrations of bulk TiO2 on sage (Salvia officinalis L.) seed germination and early growth stage. Study Design: Experiment was performed in a completely randomized design with four replications. Place and Duration of Study: The study was performed in a laboratory condition for 21 days at the College of Agriculture, Ferdowsi University of Mashhad, Iran. Methodology: The treatments in the experiment were five concentrations (5, 20, 40, 60 and 80 mg L-1) of bulk and five concentrations (5, 20, 40, 60 and 80 mg L-1) of nanosized TiO2 and an untreated control. The experiment was done in a germinator with an average temperature of 25 ±1ºC. The size of TiO2 bulk and nanoparticles were determined through Scanning Tunneling Microscope (STM). Analysis of variance was performed between treatments samples. The data were subjected to analysis of variance using SAS software. Significant levels of difference for all measured traits were calculated and means were compared by the LSD test at 5% level. Results: After 21 days of seed incubation, germination percentage improved following exposure to 60 mg L-1 bulk and nanosized TiO2. Studied treatments had not significant effects on shoot, root and seedling elongation and biomass. Exposure of sage seeds to 60 mg L-1 bulk and nanosized TiO2 obtained the lowest mean germination time (8.42 and 8.7 days, respectively) but higher concentrations did not improve mean germination time. Exposure of sage seeds to 60 mg L-1 concentrations of bulk and nano TiO2 particles led to enhanced germination rate. Conclusion: In general, there was a significant response by sage seed to nanosized TiO2 presenting the possibility of a new approach to overcome problems with seed germination in some plant species, especially medicinal plants.

14.
Artigo em Inglês | IMSEAR | ID: sea-162295

RESUMO

treatments. Increasing nanoparticles concentration above 100 ppm reduced seed germination rate. It has not found any significant effects by bulk and nanoparticles on elongation of shoot, root and seedling of wheat. Application of 100 ppm concentration of nanosized Fe2O3 reduced mean germination time (MGT) by 38.5% in comparison to the control, while 100 ppm concentration of bulk Fe2O3 did not decrease MGT in comparison with the control. The highest root biomass was achieved from concentration of 100 ppm nano- Fe2O3, but an increased concentrations of nanoparticles Fe2O3 significantly reduced root weight. Nevertheless, on the basis of these results it is highly recommended that the influence of low dose nanomaterial be assessed in order to encourage seed germination and seedling growth.

15.
J Environ Biol ; 2013 Mar; 34(2): 283-287
Artigo em Inglês | IMSEAR | ID: sea-148527

RESUMO

The aim of the study was to examine the liver tissue damage induced by nanosized-TiO2 in mouse. The biochemical parameters of liver, namely glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase and alkaline phosphatase were enhanced approximately 18%, 35% and 69% by exposure to nanosized-TiO2, respectively. The nanosized-TiO2 accumulated in the periphery of sinusoid in liver when the ultrastructure was examined through transmission electron microscopy. Enzymes, such as superoxide dismutase, catalase and aldehyde dehydrogenase were significantly inhibited by 22%, 38% and 15%, respectively, whereas glutathione peroxidase was constant following exposure to nanosized-TiO2.

16.
Chinese Pharmaceutical Journal ; (24): 1429-1433, 2013.
Artigo em Chinês | WPRIM | ID: wpr-860243

RESUMO

OBJECTIVE: To review the advances in non-invasive nano-sized preparations for ocular administration were systemically reviewed in this paper, which would aid in the development of non-invasive nano-sized ocular delivery system. METHODS: Six preparations were classified on the basis of the properties of formulations and excipients. The quality control, transportation mechanism and safety evaluation of all the dosage forms were focused on. RESULTS AND CONCLUSION: The nano-sized preparations have been grudually used in the eye disease treatment owing to their advantages including the enhancement of stability, solubility and corneal permeability, sustained ocular retention time, and improvement of the bioavailability and curative efficacy. Noninvasive administration with minimal damage to patients and side effects might have a good application prospect. However, the quality control, transportation mechanism and safety evaluation were noteworthy. It will be necessary to further develop such non-invasive nano-sized preparations for the drug delivery to ocular posterior segment.

17.
Korean Journal of Dermatology ; : 609-613, 2012.
Artigo em Coreano | WPRIM | ID: wpr-81289

RESUMO

BACKGROUND: Nano-sized water particles have been thought to moisturize the skin more effectively. However, clear benefits of humidifier generating nano-sized water particles on the skin have not been studied. OBJECTIVE: The aim of this study is to examine the effects of humidifier generating nano-sized water particles on the skin by measuring the levels of the skin hydration state and skin barrier function with an objective, quantifiable method. METHODS: A 4-week, randomized, case-control study was conducted in 40 healthy Korean women, aged between 20 and 39, and they were divided into two groups, the experimental and control groups. The experimental group used humidifier generating nano-sized water particles for 8 hours every night, during 4 weeks. Skin hydration and transepidermal water loss (TEWL) were measured every week on the forehead and cheek using corneometer and tewameter, respectively. Safety evaluations were also performed at each visit. RESULTS: The baseline skin hydration and TEWL values showed no significant differences between the two groups. After 1 week of use, the experimental group showed significantly increased skin hydration values (p<0.001, p<0.0001) and decreased levels of TEWL values (p=0.017, p=0.025) as compared to the control group. During a 4-week study period, increased skin hydration and decreased TEWL were sustained in the experimental group. No adverse effects were observed in all the volunteers. CONCLUSION: These results show that humidifier, which generates nano-sized water particles, seems to positively affect skin hydration and skin barrier function. More studies and sufficient follow-up time are needed for the assessment of the humidifier generating nano-sized water particles.


Assuntos
Idoso , Feminino , Humanos , Estudos de Casos e Controles , Bochecha , Seguimentos , Testa , Pele , Água
18.
Artigo em Inglês | IMSEAR | ID: sea-135025

RESUMO

Background: Calcium phosphate cements (CPC) is a promising materials for bone defect repair. Nanosized apatite or calcium orthophosphate has a better bioactivity than coarser crystals. Chitosan is produced commercially from chitin that is the structural element in the exoskeleton of crustaceans such as crabs and shrimp. The mixing of nanosized apatite and chitosan may provide the consistency cement, improving mechanical properties of the set bone cement. Objective: Develop nanosized apatite powder with chitosan for bone composite cement. Materials and method: Nanosized apatite was synthesized by chemical method at low temperature and used as the single-component for bone cement. The nanosized apatite powder was characterized using X-ray diffraction method, Fourier transform infrared spectroscopy, and transmission electron microscopy. CPCs were developed based on chitosan/nanosized apatite and calcium sulfate hemihydrate. The compressive strength of the set cement was measured after one to four weeks. The phase composition and the morphology of the set cements were investigated. Results: Calcium sulfate hemihydrate was effective in increasing the compressive strength after setting in a simulated body fluid for seven days. The compressive strength of chitosan/nanosized apatite composite was about 18 MPa after soaking. Conclusion: The workability and setting time of this composite were suitable to handling for bone cement. These composite cements had a significant clinical advantage for substitution of the regenerated bone.

19.
Safety and Health at Work ; : 282-289, 2011.
Artigo em Inglês | WPRIM | ID: wpr-220900

RESUMO

OBJECTIVES: We sought to establish a novel method to generate nano-sized carbon black particles (nano-CBPs) with an average size smaller than 100 nm for examining the inhalation exposure risks of experimental rats. We also tested the effect of nano-CBPs on the pulmonary and circulatory systems. METHODS: We used chemical vapor deposition (CVD) without the addition of any additives to generate nano-CBPs with a particle size (electrical mobility diameter) of less than 100nm to examine the effects of inhalation exposure. Nano-CBPs were applied to a nose-only inhalation chamber system for studying the inhalation toxicity in rats. The effect on the lungs and circulatory system was determined according to the degree of inflammation as quantified by bronchoalveolar lavage fluid (BALF). The functional alteration of the hemostatic and vasomotor activities was measured by plasma coagulation, platelet activity, contraction and relaxation of blood vessels. RESULTS: Nano-CBPs were generated in the range of 83.3-87.9 nm. Rats were exposed for 4 hour/day, 5 days/week for 4 weeks to 4.2 x 10(6), 6.2 x 10(5), and 1.3 x 10(5) particles/cm3. Exposure of nano-CBPs by inhalation resulted in minimal pulmonary inflammation and did not appear to damage the lung tissue. In addition, there was no significant effect on blood functions, such as plasma coagulation and platelet aggregation, or on vasomotor function. CONCLUSION: We successfully generated nano-CBPs in the range of 83.3-87.9 nm at a maximum concentration of 4.2 x 10(6) particles/cm3 in a nose-only inhalation chamber system. This reliable method can be useful to investigate the biological and toxicological effects of inhalation exposure to nano-CBPs on experimental rats.


Assuntos
Animais , Ratos , Plaquetas , Líquido da Lavagem Broncoalveolar , Carbono , Contratos , Inflamação , Inalação , Exposição por Inalação , Pulmão , Tamanho da Partícula , Plasma , Agregação Plaquetária , Pneumonia , Relaxamento , Fuligem
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