RESUMO
We present a size-based sorting method for nanoparticles in microfluidics with the aid of light-patterned dielectrophoresis (DEP) force. In a microfluidic channel, we have succeeded in manipulating a random distribution of particles into a single stream with the DEP force as well as the hydrodynamic force, and more strikingly, the trajectory of particles is found to be size-dependent, implicating that we can precisely separate nanoparticles based on their sizes even if they are identical in mass. We have numerically predicted the behavior of sorting nanoparticles, emphasizing on the size, velocity and electrical permittivity, so as to know their influences on the effective sorting, particularly in terms of high throughput. Our work confirms that what we believe to be the novel manipulation of nanoparticles features its flexibility as well as high throughput.
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ß-alanine is the only naturally occurring ß-amino acid, which is widely used in medicine, food, and feed fields, and generally produced through synthetic biological methods based on engineered strains of Escherichia coli or Corynebacterium glutamicum. However, the ß-alanine biosynthesis in Bacillus subtilis, a traditional industrial model microorganism of food safety grade, has not been thoroughly explored. In this study, the native l-aspartate-α-decarboxylase was overexpressed in B. subtilis 168 to obtain an increase of 842% in ß-alanine production. A total of 16 single-gene knockout strains were constructed to block the competitive consumption pathways to identify a total of 6 genes (i.e., ptsG, fbp, ydaP, yhfS, mmgA, and pckA) involved in ß-alanine synthesis, while the multigene knockout of these 6 genes obtained an increased ß-alanine production by 40.1%. Ten single-gene suppression strains with the competitive metabolic pathways inhibited revealed that the inhibited expressions of genes glmS, accB, and accA enhanced the ß-alanine production. The introduction of heterologous phosphoenolpyruvate carboxylase increased the ß-alanine production by 81.7%, which was 17-fold higher than that of the original strain. This was the first study using multiple molecular strategies to investigate the biosynthetic pathway of ß-alanine in B. subtilis and to identify the genetic factors limiting the excessive synthesis of ß-alanine by microorganisms.
Assuntos
Bacillus subtilis , Corynebacterium glutamicum , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Redes e Vias Metabólicas , beta-Alanina/metabolismo , Vias BiossintéticasRESUMO
BACKGROUND: Heme is an iron/porphyrin complex compound, widely used in the health care, food, and pharmaceutical industries. It is more advantageous and attractive to develop microbial cell factories to produce heme by fermentation, with lower production costs and environmentally more friendly procedures than those of the traditional extraction based on animal blood. In this study, Bacillus subtilis, a typical industrial model microorganism of food safety grade, was used for the first time as the host to synthesize heme. RESULTS: The heme biosynthetic pathway was engineered as four modules, the endogenous C5 pathway, the heterologous C4 pathway, the uroporphyrinogen (urogen) III synthesis pathway, and the downstream synthesis pathway. Knockout of hemX encoding the negative effector of the concentration of HemA, overexpression of hemA encoding glutamyl-tRNA reductase, and knockout of rocG encoding the major glutamate dehydrogenase in the C5 pathway, resulted in an increase of 427% in heme production. Introduction of the heterologous C4 pathway showed a negligible effect on heme biosynthesis. Overexpression of hemCDB, which encoded hydroxymethylbilane synthase, urogen III synthase, and porphobilinogen synthase participating in the urogen III synthesis pathway, increased heme production by 39%. Knockouts of uroporphyrinogen methyltransferase gene nasF and both heme monooxygenase genes hmoA and hmoB in the downstream synthesis pathway increased heme production by 52%. The engineered B. subtilis produced 248.26 ± 6.97 mg/L of total heme with 221.83 ± 4.71 mg/L of extracellular heme during the fed-batch fermentation in 10 L fermenter. CONCLUSIONS: Strengthening endogenous C5 pathway, urogen III synthesis pathway and downstream synthesis pathway promoted the biosynthesis of heme in B. subtilis. The engineered B. subtilis strain has great potential as a microbial cell factory for efficient industrial heme production.
Assuntos
Bacillus subtilis , Heme , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Heme/metabolismo , Engenharia Metabólica/métodos , Fermentação , Uroporfirinogênios/metabolismoRESUMO
OBJECTIVE: To explore the relationships between plasma adiponectin levels and risk of breast cancer by molecular subtype. METHODS: A case-control study including 437 histopathologic confirmed primary breast cancer cases and 469 healthy female controls was conducted between April 2014 and May 2015. Basic information of the participants were collected using a structured questionnaire. Blood samples were collected and the plasma adiponectin levels were measured by enzyme-linked immunosorbent assay (ELASA). Analysis of variance (ANOVA) was used to compare the differences of plasma adiponectin levels among the control group and the breast cancer groups with different molecular subtypes. Multinomial logistic regression was used to investigate the association between plasma adiponectin levels and risk of breast cancer by molecular subtypes. All the statistical analyses were stratified by menopausal status. RESULTS: Among the 437 breast cancer cases, there were 310 Luminal breast cancer cases, 83 HER-2-enriched breast cancer cases and 44 basal-like breast cancer cases. The median (P25, P75) of plasma adiponectin level of the controls was 14.85 (9.69, 21.35) µg/mL. The medians (P25, P75) of plasma adiponectin levels of the cases were 11.74 (8.15, 16.14) µg/mL, 12.02(8.43, 16.96) µg/mL and 12.67(8.25, 17.27) µg/mL for Luminal, HER-2-enriched and basal-like subtype respectively, which were statistically different from the controls (P < 0.001). Multinomial logistic regression showed that, after adjustment for the confounders, the higher levels of plasma adiponectin were associated with the lower risks of pre-menopausal Luminal breast cancer (ORpre-menopausal Luminal=0.50, 95%CI: 0.27-0.92, Ptrend=0.001), post-menopausal Luminal breast cancer (ORpost-menopausal Luminal=0.06, 95%CI: 0.02-0.23, Ptrend < 0.001) and post-menopausal HER-2-enriched breast cancer (ORpost-menopausal HER-2-enriched=0.06, 95%CI: 0.01-0.62, Ptrend=0.001). CONCLUSION: Lower levels of plasma adiponectin may increase the risk of pre-menopausal and post-menopausal Luminal breast cancer and post-menopausal HER-2-enriched breast cancer.
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Adiponectina/sangue , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/sangue , Neoplasias da Mama/classificação , Estudos de Casos e Controles , Feminino , Humanos , Fatores de RiscoRESUMO
Lanthanide upconversion nanophosphors (Ln-UCNPs) have attracted great attention in a variety of fields, benefiting from low background fluorescence interference and a high signal-to-noise ratio of upconversion luminescence. However, the establishment of Ln-UCNPs with dual near-infrared (NIR) emission channels still remains challenging. Herein, we report the design and synthesis of Nd3+-sensitized NaYbF4:Tm@NaYF4:Yb@NaNdF4:Yb hierarchical-structured nanoparticles that emit NIR luminescence at 696 and 980 nm under excitation at 808 nm. The sensitizer-rich NaYbF4 core promotes efficient energy transfer to Tm3+. The interlayer of NaYF4:Yb effectively prevents the cross-relaxation process from Tm3+ to Nd3+ and thus enhances the luminescence emission. The introduction of Nd3+ ion as the sensitizer transforms the excitation wavelength from 980 to 808 nm, which subtly averts the laser-induced thermal effect and offers a new pathway for the NIR emission channel at 980 nm. The as-prepared nanoparticles were further applied in developing latent and blood fingerprint images, which exhibited high signal-to-noise ratio and distinguishable details under 808 nm excitation with negligible thermal damage to the sample. Our work provides a promising strategy to realize NIR-to-NIR dual-channel emissions in Ln-UCNPs. With further functionalization, such nanoparticles are expected to have great potential in forensic and biological sciences.
Assuntos
Substâncias Luminescentes/química , Nanopartículas/química , Neodímio/química , Manchas de Sangue , Dermatoglifia , Calefação , Humanos , Raios Infravermelhos , Medições Luminescentes , Razão Sinal-Ruído , TemperaturaRESUMO
Nitroreductase (NTR) can be overexpressed in hypoxic tumors, thus the selective and efficient detection of NTR is of great importance. To date, although a few optical methods have been reported for the detection of NTR in solution, an effective optical probe for NTR monitoring in vivo is still lacking. Therefore, it is necessary to develop a near-infrared (NIR) fluorescent detection probe for NTR. In this study, five NIR cyanine dyes with fluorescence reporting structure decorated with different nitro aromatic groups, Cy7-1-5, have been designed and explored for possible rapid detection of NTR. Our experimental results presented that only a para-nitro benzoate group modified cyanine probe (Cy7-1) could serve as a rapid NIR fluorescence-enhanced probe for monitoring and bioimaging of NTR. The structure-function relationship has been revealed by theoretical study. The linker connecting the detecting and fluorescence reporting groups and the nitro group position is a key factor for the formation of hydrogen bonds and spatial structure match, inducing the NTR catalytic ability enhancement. The in vitro response and mechanism of the enzyme-catalyzed reduction of Cy7-1 have been investigated through kinetic optical studies and other methods. The results have indicated that an electro-withdrawing group induced electron-transfer process becomes blocked when Cy7-1 is catalytically reduced to Cy7-NH2 by NTR, which is manifested in enhanced fluorescence intensity during the detection process. Confocal fluorescence imaging of hypoxic A549 cells has confirmed the NTR detection ability of Cy7-1 at the cellular level. Importantly, Cy7-1 can detect tumor hypoxia in a murine hypoxic tumor model, showing a rapid and significant enhancement of its NIR fluorescence characteristics suitable for fluorescence bioimaging. This method may potentially be used for tumor hypoxia diagnosis.
Assuntos
Benzotiazóis/química , Carbocianinas/química , Corantes Fluorescentes/química , Nitrorredutases/análise , Imagem Óptica , Animais , Linhagem Celular Tumoral , Fluorescência , Humanos , Hipóxia/enzimologia , Camundongos , Microscopia Confocal , Microscopia de Fluorescência , Simulação de Acoplamento Molecular , Neoplasias/enzimologia , Imagem Corporal TotalRESUMO
Deposition of extracellular amyloid-ß (Aß) peptide is one of the pathological hallmarks of Alzheimer's disease (AD). Accumulation of Aß is thought to associate with cognition deficits, neuroinflammation and apoptosis observed in AD. However, effective neuroprotective approaches against Aß neurotoxicity are unavailable. In the present study, we analysed the effects of pranlukast, a selective cysteinyl leukotriene receptor 1 (CysLT1R) antagonist, on the impairment of learning and memory formation induced by Aß and the probable underlying electrophysiological and molecular mechanisms. We found that bilateral intrahippocampal injection of Aß1â42 resulted in a significant decline of spatial learning and memory of mice in the Morris water maze (MWM) and Y-maze tests, together with a serious depression of in vivo hippocampal long-term potentiation (LTP) in the CA1 region of the mice. Importantly, this treatment caused significant increases in CysLT1R expression and subsequent NF-κB signaling, caspase-3 activation and Bcl-2 downregulation in the hippocampus or prefrontal cortex. Oral administration of pranlukast at 0.4 or 0.8 mg/kg for 4 wk significantly reversed Aß1â42-induced impairments of cognitive function and hippocampal LTP in mice. Furthermore, pranlukast reversed Aß1â42-induced CysLT1R upregulation, and markedly suppressed the Aß1â42-triggered NF-κB pathway, caspase-3 activation and Bcl-2 downregulation in the hippocampus and prefrontal cortex in mice. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay confirmed its presence in the brain after oral administration of pranlukast in mice. These data disclose novel findings about the therapeutic potential of pranlukast, revealing a previously unknown therapeutic possibility to treat memory deficits associated with AD.
Assuntos
Peptídeos beta-Amiloides/farmacologia , Cromonas/farmacologia , Transtornos Cognitivos/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Antagonistas de Leucotrienos/farmacologia , Fragmentos de Peptídeos/farmacologia , Peptídeos beta-Amiloides/administração & dosagem , Animais , Comportamento Animal/efeitos dos fármacos , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/fisiopatologia , Cromonas/administração & dosagem , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/fisiopatologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Hipocampo/fisiopatologia , Aprendizagem/efeitos dos fármacos , Antagonistas de Leucotrienos/administração & dosagem , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/fisiologia , Masculino , Memória/efeitos dos fármacos , Camundongos Endogâmicos ICR , Fragmentos de Peptídeos/administração & dosagem , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiopatologia , Receptores de Leucotrienos/efeitos dos fármacosRESUMO
Research-oriented hospitals are responsible for medical services tasks, medical education, and scientific research, playing an important role in medical research and application. The research efficiency of a clinical specialty is influenced by factors such as the characteristics of the specialty, the organizational atmosphere, and the clinical director's leadership. The present study aimed to describe the research efficiency of clinical specialties, explore the factors influencing it, and clarify the argument of co-evolution theory regarding the collaborative development of medical services, education, and research. Logistic regression and multiple linear regression were adopted to estimate the correlation between influencing factors and scientific research efficiency. Hospital H, which is representative of research hospitals in China, was taken as an example. Taking three efficiency values-comprehensive technical efficiency (CTE), pure technical efficiency (PTE), and scale efficiency (SE)-as dependent variables, the independent variables affecting research productivity were statistically analyzed. This study also examined the scientific research efficiency of 41 specialties between 2013 and 2017, and found that the independent variables affected CTE, PTE, and SE to various degrees. Collaborative innovation in medical education and research must be based on clinical research; how to balance medical and teaching quality, and research efficiency requires further discussion. While young people play a major role on the research team because of their creativity and initiatives, which improve CTE and PTE, high-level researchers with better research and leadership abilities lead to the rational allocation and effective utilization of resources, thus improving SE. In 2013-2017, discipline construction focused on scale expansion, resulting in the decline of SE in China. Therefore, this study suggests further improvements for the efficiency of clinical specialties in research hospitals.
Assuntos
Pesquisa Biomédica/normas , Recursos em Saúde/normas , Hospitais , Biometria , China/epidemiologia , Eficiência Organizacional , Humanos , LiderançaRESUMO
A specific and rational index system is key to scientific research evaluation. According to the characteristics and status of research-oriented hospitals in China, this study aimed to construct a comprehensive and methodical system for scientific research evaluation. Using bibliometric research, we sorted and refined indices for both domestic and international scientific research evaluation systems, established two-dimensional indices of input and output, and constructed the theoretical framework of evaluation after experts. The Delphi method was adopted to determine the evaluation indices at all levels, and the Analytic Hierarchy Process was used to calculate the weights of the indices at all levels. Twenty experts from different medical fields were involved in the 2 rounds study. Altogether, 7 primary, 14 secondary, and 37 tertiary indices were included in the evaluation system. A matrix was built to conduct the maximum eigenvalue, the consistency indices, and the consistency ratio of each expert in the survey. The index weight coefficients of the indices were calculated accordingly. The model exhibited high consistency, and the credibility of the results was verified. The evaluation system for research-oriented hospitals that we established had high specificity, credibility, and rationality. The evaluation system that we established combines some quantitative evaluation indicators, which are subsequently weighted according to their importance in the field of research-oriented hospital. Evaluation index system will provide the practical manner in the future for comparing the potential academic level and impact of research-oriented hospitals. Moreover, further verification, adjustments, and optimization of the system and indicators will be performed in follow-up empirical studies.
Assuntos
Hospitais , China , Técnica Delphi , Humanos , Inquéritos e QuestionáriosRESUMO
Combinational administration of chemotherapy (CT) and photothermal therapy (PTT) has been widely used to treat cancer. However, the scheduling of CT and PTT and how it will affect the therapeutic efficacy has not been thoroughly investigated. The challenge is to realize the sequence control of these two therapeutic modes. Herein, we design a temperature sensitive upconversion nanocomposite for CT-PTT combination therapy. By monitoring the microscopic temperature of the nanocomposite with upconversion luminescence, photothermal effect can be adjusted to achieve thermally triggered combination therapy with a sequence of CT, followed by PTT. We find that CT administered before PTT results in better therapeutic effect than other administration sequences when the dosages of chemodrug and heat are kept at the same level. This work proposes a programmed method to arrange the process of combination cancer therapy, which takes full advantage of each therapeutic mode and contributes to the development of new cancer therapy strategies.
Assuntos
Doxorrubicina/farmacologia , Nanocompostos/química , Neoplasias/terapia , Fototerapia/métodos , Temperatura , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Terapia Combinada/métodos , Doxorrubicina/química , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos SCID , Nanocompostos/ultraestrutura , Neoplasias/patologia , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/efeitos da radiação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: The incidence of cancer, diabetes, and autoimmune diseases has been increasing. Furthermore, there are more and more patients with solid organ transplants. The survival rate of these immunocompromised individuals is extremely low when they are severely hit-on. In this study, we established cardiac arrest cardiopulmonary resuscitation (CPR) model in severe combined immunodeficient (SCID) mice, analyzed the expression and activation of mitochondrial autophagy and NLRP3 inflammasome/caspase-1, and explored mitochondrial repair and inflammatory injury in immunodeficiency individual during systemic ischemia-reperfusion injury. METHODS: A potassium chloride-induced cardiac arrest model was established in C57BL/6 and nonobese diabetic/SCID (NOD/SCID) mice. One hundred male C57BL/6 mice and 100 male NOD/SCID mice were randomly divided into five groups (control, 2 h post-CPR, 12 h post-CPR, 24 h post-CPR, and 48 h post-CPR). A temporal dynamic view of alveolar epithelial cells, macrophages, and neutrophils from bronchoalveolar lavage fluid (BALF) was obtained using Giemsa staining. Spatial characterization of phenotypic analysis of macrophages in the lung interstitial tissue was analyzed by flow cytometry. The morphological changes of mitochondria 48 h after CPR were studied by transmission electron microscopy and quantified according to the Flameng grading system. Western blotting analysis was used to detect the expression and activation of the markers of mitochondrial autophagy, NLRP3 inflammasome, and caspase-1. RESULTS: (1) In NOD/SCID mice, macrophages were disintegrated in BALF, and many alveolar epithelial cells were shed at 48 h after resuscitation. Compared with C57BL/6 mice, the ratio of macrophages/total cells peaked at 12 h and was significantly higher in NOD/SCID mice (31.17 ± 4.13 vs. 49.69 ± 2.43, t = 14.46, P = 0.001). After 24 h, the results showed a downward trend. Furthermore, a large number of macrophages were disintegrated in the BALF. (2) Mitochondrial autophagy was present in both C57BL/6 and NOD/SCID mice after CPR, but it began late in the NOD/SCID mice. Compared with C57BL/6 mice, phos-ULK1 (Ser327) expression was significantly lower at 2 h and 12 h after CPR (2 h after CPR: 1.88 ± 0.36 vs. 1.12 ± 0.11, t = -1.36, P < 0.01 and 12 h after CPR: 1.52 ± 0.16 vs. 1.05 ± 0.12, t = -0.33, P < 0.01), whereas phos-ULK1 (Ser757) expression was significantly higher at 2 h and 12 h after CPR in NOD/SCID mice (2 h after CPR: 1.28 ± 0.12 vs. 1.69 ± 0.14, t = 1.7, P < 0.01 and 12 h after CPR: 1.33 ± 0.10 vs. 1.94 ± 0.13, t = 2.75, P < 0.01). (3) Furthermore, NLRP3 inflammasome/caspase-1 activation in the pulmonary tissues occurred early and for only a short time in C57BL/6 mice, but this phenomenon was sustained in NOD/SCID mice. The expression of the NLRP3 inflammasome increased modestly in the C57 mice, but the increase was higher in the NOD/SCID mice than in the C57BL/6 mice, especially at 12, 24, 48 h after CPR (48 h after CPR: 1.46 ± 0.13 vs. 2.97 ± 0.19, t = 5.34, P = 0.001). The expression of caspase-1-20 generally followed the same pattern as the NLRP3 inflammasome. CONCLUSIONS: There is a regulatory relationship between the NLRP3 inflammasome and mitochondrial autophagy after CPR in the healthy mice. This regulatory relationship was disturbed in the NOD/SCID mice because the signals for mitochondrial autophagy occurred late, and NLRP3 inflammasome- and caspase-1-dependent cell injury was sustained.
Assuntos
Autofagia/fisiologia , Inflamassomos/metabolismo , Animais , Parada Cardíaca/metabolismo , Parada Cardíaca/fisiopatologia , Pulmão/metabolismo , Pulmão/fisiopatologia , Macrófagos/metabolismo , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Mitocôndrias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismoRESUMO
Development of multidrug resistance (MDR) is a continuous clinical challenge partially due to the overexpression of P-glycoprotein (P-gp) for chronic myelogenous leukemia (CML) patients. Herein, we evaluated the inhibitory potency of emodin, a natural anthraquinone derivative isolated from Rheum palmatum L, on P-gp in P-gp positive K562/ADM cells. Competition experiments combined with molecular docking analysis were utilized to investigate the binding modes between emodin and binding sites of P-gp. Emodin reversed adriamycin resistance in K562/ADM cells accompanied with the decrease of P-gp protein expression, further increasing the uptake of rhodamine123 in both K562/ADM and Caco-2 cells, indicating the inhibition of P-gp efflux function. Moreover, when incubated with emodin under different conditions where P-gp was inhibited, K562/ADM cells displayed increasing intracellular uptake of emodin, suggesting that emodin may be the potential substrate of P-gp. Importantly, rhodamine 123 could increase the Kintrinsic (Ki) value of emodin linearly, whereas, verapamil could not, implying that emodin competitively bound to the R site of P-gp and noncompetition existed between emodin and verapamil at the M site, in a good accordance with the results of molecular docking that emodin bound to the R site of P-gp with higher affinity. Based on our results, we suggest that emodin might be used to modulate P-gp function and expression.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Emodina/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos Fitogênicos/química , Sítios de Ligação , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Emodina/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Simulação de Acoplamento MolecularRESUMO
Photothermal therapy (PTT) at present, following the temperature definition for conventional thermal therapy, usually keeps the temperature of lesions at 42-45 °C or even higher. Such high temperature kills cancer cells but also increases the damage of normal tissues near lesions through heat conduction and thus brings about more side effects and inhibits therapeutic accuracy. Here we use temperature-feedback upconversion nanoparticle combined with photothermal material for real-time monitoring of microscopic temperature in PTT. We observe that microscopic temperature of photothermal material upon illumination is high enough to kill cancer cells when the temperature of lesions is still low enough to prevent damage to normal tissue. On the basis of the above phenomenon, we further realize high spatial resolution photothermal ablation of labelled tumour with minimal damage to normal tissues in vivo. Our work points to a method for investigating photothermal properties at nanoscale, and for the development of new generation of PTT strategy.
Assuntos
Retroalimentação , Temperatura Alta/uso terapêutico , Mioblastos , Nanocompostos , Nanopartículas , Neoplasias/terapia , Fototerapia , Animais , Linhagem Celular , Sobrevivência Celular , Células HeLa , Humanos , Técnicas In Vitro , Camundongos , Nanotecnologia , TemperaturaRESUMO
Hormone replacement therapy (HRT) plays an important role in the treatment and prevention of osteoporosis. Here, 17ß-estradiol (E2)-loaded PEGlyated upconversion nanoparticles (E2-UCNP@pPEG) were synthesized that retained E2 bioactivity and improved delivery efficiency over a relatively long time-period. E2-UCNP@pPEG was synthesized and characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR), among other methods. The loading efficiency of E2 was determined to be 14.5 wt %, and the nanocarrier effectively facilitated sustained release. Confocal upconversion luminescence (UCL) imaging using the CW 980 nm laser as excitation resource revealed significant interactions of E2-UCNP@pPEG with preosteoblasts. E2-UCNP@pPEG treatment of preosteoblasts induced positive effects on differentiation, matrix maturation, and mineralization. Moreover, in situ and ex vivo UCL imaging studies disclosed that E2 encapsulated in the nanocomposite was passively delivered to bone. Our results collectively suggest that this nanoreservoir provides an effective drug-loading system for hormonelike drug delivery and support its considerable potential as a therapeutic agent for osteoporosis.
Assuntos
Preparações de Ação Retardada/química , Estradiol/administração & dosagem , Estradiol/química , Nanocápsulas/química , Osteoblastos/química , Polietilenoglicóis/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/toxicidade , Difusão , Estradiol/toxicidade , Terapia de Reposição Hormonal/métodos , Camundongos , Nanocápsulas/toxicidade , Nanocápsulas/ultraestrutura , Osteoblastos/efeitos dos fármacos , Polietilenoglicóis/toxicidadeRESUMO
Montelukast, known as a cysteinyl leukotriene receptor 1 (CysLT1R) antagonist, is currently used for treatment of inflammatory diseases such as asthma. Here, we investigated effects of montelukast on neuroinflammatory, apoptotic responses, and memory performance following intracerebral infusions of amyloid-ß (Aß). The data demonstrated that intracerebroventrical infusions of aggregated Aß1-42 (410 pmol/mouse) produced deficits in learning ability and memory, as evidenced by increase in escape latency during acquisition trials and decreases in exploratory activities in the probe trial in Morris water maze (MWM) task, and by decrease in the number of correct choices and increase in latency to enter the shock-free compartment in Y-maze test, and caused significant increases in pro-inflammatory cytokines such as NF-κB p65, TNF-α and IL-1ß as well as pro-apoptotic molecule caspase-3 activation and anti-apoptotic protein Bcl-2 downregulation in hippocampus and cortex. Interestingly, this treatment resulted in upregulation of protein or mRNA of CysLT1R in both hippocampus and cortex. Blockade of CysLT1R by repeated treatment with montelukast (1 or 2 mg/kg, ig, 4 weeks) reduced Aß1-42-induced CysLT1R expression and also suppressed Aß1-42-induced increments of NF-κB p65, TNF-α, IL-1ß and caspase-3 activation, and Bcl-2 downregulation in the hippocampus and cortex. Correspondingly, montelukast treatment significantly improved Aß1-42-induced memory impairment in mice, but had little effect on normal mice. Our results show that montelukast may ameliorate Aß1-42-induced memory impairment via inhibiting neuroinflammation and apoptosis mediated by CysLT1R signaling, suggesting that CysLT1R antagonism represents a novel treatment strategy for Alzheimer's disease.
Assuntos
Acetatos/farmacologia , Peptídeos beta-Amiloides/metabolismo , Apoptose/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/metabolismo , Quinolinas/farmacologia , Receptores de Leucotrienos/metabolismo , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/fisiologia , Caspase 3/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiopatologia , Ciclopropanos , Citocinas/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Antagonistas de Leucotrienos/farmacologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/fisiopatologia , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/metabolismo , Nootrópicos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , SulfetosRESUMO
AIMS: Pioglitazone, known as a peroxisome proliferator-activated receptor γ (PPARγ) agonist, is used to treat type 2 diabetes mellitus (T2DM). T2DM has been associated with reduced performance on numerous domains of cognitive function. Here, we investigated the effects of pioglitazone on memory impairment in a mouse model with defects in insulin sensitivity and secretion, namely high-fat diet (HFD) streptozotocin (STZ)-induced diabetic mice. METHODS: ICR mice were fed with HFD for 4 weeks and then injected with a single low dose of STZ followed by continued HFD feeding for an additional 4 weeks. Pioglitazone (18 mg/kg, 9 mg/kg body weight) was orally administered for 6 weeks once daily. Y-maze test and Morris water maze test (MWM) were employed for testing learning and memory. Serum glucose, serum insulin, serum triglyceride, brain ß-amyloid peptide (Aß), brain ß-site amyloid precursor protein cleaving enzyme (BACE1), brain nuclear factor κB (NF-κB), and brain receptor for advanced glycation end products (RAGE) were also tested. RESULTS: The STZ/HFD diabetic mice, characterized by hyperglycemia, hyperlipemia and hypoinsulinemia, performed poorly on Y-maze and MWM hence reflecting impairment of learning and memory behavior with increases of Aß40/Aß42, BACE1, NF-κB, and RAGE in brain. Treatment of PPARγ agonist, pioglitazone (18 or 9 mg/kg body weight), significantly reversed diabetes-induced impairment of learning and memory behavior, which is involved in decreases of Aß40/Aß42 via inhibition of NF-κB, BACE1 and RAGE in brain as well as attenuation of hyperglycemia, hyperlipemia, and hypoinsulinemia. CONCLUSIONS: It is concluded that PPARγ agonist pioglitazone may be considered as potential pharmacological agents for the management of cognitive dysfunction in T2DM.