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1.
ACS Appl Mater Interfaces ; 15(23): 27706-27718, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37261936

RESUMO

Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, with ineffective treatment and poor prognosis. It is in great demand to develop a novel theranostic strategy for accurate diagnosis and targeted treatment of TNBC. In the present study, one nanoplatform (HA-ICG-Fe-PDA), endowed with multimodal imaging-guided chemodynamic/photodynamic/photothermal (CDT/PDT/PTT) synergistic therapy capacity toward TNBC, was innovatively constructed. The nanoplatform was prepared by covalently conjugating ICG-decorated hyaluronic acid (HA) on Fe3+-chelated polydopamine (PDA). HA facilitated the targeting and accumulating of the nanoplatform in tumor tissue and cells of TNBC, thus producing enhanced magnetic resonance signal. Upon entering into TNBC cells, the intracellular hyaluronidase-catalyzed cleavage of HA-ICG-Fe-PDA activated the prequenched near-infrared (NIR) fluorescence signal, allowing for the activatable NIR fluorescence imaging. On the other hand, Fe3+ in the nanoplatform could be reduced to reactive Fe2+ in tumor microenvironment, guaranteeing efficient Fenton reaction-mediated CDT. The combination of ICG with Fe-PDA enhanced the NIR absorption of the nanoplatform so that considerable PTT/PDT and photothermal imaging were achieved under 808 nm laser irradiation. In vitro and in vivo experiments have verified that the proposed nanoplatform integrates the potential of TNBC-targeting, precise NIR fluorescence/magnetic resonance/photothermal trimodal imaging, efficient treatment via synergistic CDT/PDT/PTT, as well as excellent biocompatibility. Therefore, this multifunctional nanoplatform provides a simple and versatile strategy for imaging-guided theranostics of TNBC.


Assuntos
Nanopartículas , Fotoquimioterapia , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Terapia Fototérmica , Linhagem Celular Tumoral , Fototerapia , Fotoquimioterapia/métodos , Nanomedicina Teranóstica , Microambiente Tumoral
2.
Antioxidants (Basel) ; 12(1)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36671015

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease characterized by progressive loss of dopaminergic neurons in the substantia nigra of the midbrain. The etiology of PD has yet to be elucidated, and the disease remains incurable. Increasing evidence suggests that oxidative stress is the key causative factor of PD. Due to their capacity to alleviate oxidative stress, antioxidants hold great potential for the treatment of PD. Vitamins are essential organic substances for maintaining the life of organisms. Vitamin deficiency is implicated in the pathogenesis of various diseases, such as PD. In the present study, we investigated whether administration of vitamin B12 (VB12) could ameliorate PD phenotypes in vitro and in vivo. Our results showed that VB12 significantly reduced the generation of reactive oxygen species (ROS) in the rotenone-induced SH-SY5Y cellular PD model. In a Parkin gene knockout C. elegans PD model, VB12 mitigated motor dysfunction. Moreover, in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse PD model, VB12 also displayed protective effects, including the rescue of mitochondrial function, dopaminergic neuron loss, and movement disorder. In summary, our results suggest that vitamin supplementation may be a novel method for the intervention of PD, which is safer and more feasible than chemical drug treatment.

3.
Front Immunol ; 13: 940929, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35860234

RESUMO

The purpose of this study is to assess the feasibility of astaxanthin-rich Oedocladium carolinianum as an immunostimulant in the diet for Trachinotus ovatus. Three experimental diets containing 0% (OC0), 1% (OC1), and 5% (OC5) O. carolinianum powder were formulated for 6-week feeding trials. The results indicated that the OC5 diet boosted the growth performance through decreasing the feed conversion ratio and increasing digestive enzyme activities and intestinal villus length. Meanwhile, fish fed with the OC5 diet promoted antioxidant ability via stimulating the Nrf2-ARE signal pathway and enhancing antioxidant enzyme activities. Furthermore, the OC5 diet exerted hepatoprotective effects by suppressing the lipid deposition and inflammation response and enhancing the transport capacity of cholesterol. Besides, the OC5 diet improved the non-specific immunity by activating the lysozyme and complement system and increasing the nitric oxide content and total nitric oxide synthase activity. Dietary O. carolinianum supplementation promoted the deposition of astaxanthin in the whole body. Therefore, a diet supplemented with 5% O. carolinianum is recommended to boost the growth, antioxidant capacity, immune response, and flesh quality of T. ovatus.


Assuntos
Antioxidantes , Perciformes , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Suplementos Nutricionais , Peixes/metabolismo , Imunidade
4.
Curr Top Med Chem ; 20(30): 2789-2800, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33076809

RESUMO

Traditional Chinese Medicine (TCM) is one of the ancient and most accepted alternative medicinal systems in the world for the treatment of health ailments. World Health Organization recognizes TCM as one of the primary healthcare practices followed across the globe. TCM utilizes a holistic approach for the diagnosis and treatment of cancers. The tumor microenvironment (TME) surrounds cancer cells and plays pivotal roles in tumor development, growth, progression, and therapy resistance. TME is a hypoxic and acidic environment that includes immune cells, pericytes, fibroblasts, endothelial cells, various cytokines, growth factors, and extracellular matrix components. Targeting TME using targeted drug delivery and nanoparticles is an attractive strategy for the treatment of solid tumors and recently has received significant research attention under precise medicine concept. TME plays a pivotal role in the overall survival and metastasis of a tumor by stimulating cell proliferation, preventing the tumor clearance by the immune cells, enhancing the oncogenic potential of the cancer cells, and promoting tumor invasion. Hepatocellular Carcinoma (HCC) is one of the major causes of cancer-associated deaths affecting millions of individuals worldwide each year. TCM herbs contain several bioactive phytoconstituents with a broad range of biological, physiological, and immunological effects on the system. Several TCM herbs and their monomers have shown inhibitory effects in HCC by controlling the TME. This study reviews the fundamentals and applications of targeting strategies for immunosuppressing TME to treat cancers. This study focuses on TME targeting strategies using TCM herbs and the molecular mechanisms of several TCM herbs and their monomers on controlling TME.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Medicina Tradicional Chinesa , Nanopartículas/química , Antineoplásicos/química , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Humanos , Neoplasias Hepáticas/patologia , Microambiente Tumoral/efeitos dos fármacos
5.
Bioresour Technol ; 316: 123902, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32738560

RESUMO

Tribonema minus was cultivated in different concentrations of sugarcane wastewater (SW) diluted with mBG-11 medium to produce biomass for biodiesel, bioproduct, and biomaterial production. The results showed that T. minus grew mixotrophically in 50%SW, with the highest biomass accumulation (7.86 g/L) and nutrient removal efficiency (84.85% of nitrogen, 62.57% of phosphorus, and 44.72% of COD). Excluding 100%SW, the chrysolaminarin and cellulose contents increased with increasing SW concentration; the highest contents of 8.11% and 25.69% dry weight were reached in 75%SW, respectively. Although fewer lipids and palmitoleic acid accumulated at higher SW concentrations, their productivities were significantly higher than those in the control due to the higher contribution of biomass. Moreover, the fatty acid profiles produced at the tested concentrations showed superior biodiesel properties. These findings suggested that the addition of mBG-11 medium to SW might be an effective strategy for valuable biomass production in T. minus and SW bioremediation.


Assuntos
Microalgas , Águas Residuárias , Biocombustíveis , Biomassa , Bengala , Nitrogênio/análise , Fósforo , Açúcares
6.
Neuromolecular Med ; 22(2): 218-226, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31664682

RESUMO

Mutations in LRRK2 are currently recognized as the most common monogenetic cause of Parkinsonism. The elevation of kinase activity of LRRK2 that frequently accompanies its mutations is widely thought to contribute to its toxicity. Accordingly, many groups have developed LRRK2-specific kinase inhibitors as a potential therapeutic strategy. Given that protein phosphorylation is a reversible event, we sought to elucidate the phosphatase(s) that can reverse LRRK2-mediated phosphorylation, with the view that targeting this phosphatase(s) may similarly be beneficial. Using an unbiased RNAi phosphatase screen conducted in a Drosophila LRRK2 model, we identified PP2A as a genetic modulator of LRRK2-induced neurotoxicity. Further, we also identified ribosomal S6 kinase (S6K), a target of PP2A, as a novel regulator of LRRK2 function. Finally, we showed that modulation of PP2A or S6K activities ameliorates LRRK2-associated disease phenotype in Drosophila.


Assuntos
Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/enzimologia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Proteína Fosfatase 2/fisiologia , Proteínas Quinases S6 Ribossômicas/fisiologia , Animais , Animais Geneticamente Modificados , Linhagem Celular , Ceramidas/farmacologia , Modelos Animais de Doenças , Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/metabolismo , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Cloridrato de Fingolimode/farmacologia , Mutação com Ganho de Função , Técnicas de Silenciamento de Genes , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Mutação de Sentido Incorreto , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/fisiologia , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 2/antagonistas & inibidores , Proteína Fosfatase 2/genética , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas Recombinantes/metabolismo , Proteínas Quinases S6 Ribossômicas/antagonistas & inibidores , Proteínas Quinases S6 Ribossômicas/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/antagonistas & inibidores , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo
7.
Neuromolecular Med ; 22(1): 56-67, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31401719

RESUMO

Parkinson's disease (PD), the most common neurodegenerative movement disorder, is characterized by the progressive loss of dopaminergic neurons in substantia nigra. The underlying mechanisms of PD pathogenesis have not been fully illustrated and currently PD remains incurable. Accumulating evidences suggest that mitochondrial dysfunction plays pivotal role in the dopaminergic neuronal death. Therefore, discovery of novel and safe agent for rescuing mitochondrial dysfunction would benefit PD treatment. Here we demonstrated for the first time that α-Arbutin (Arb), a natural polyphenol extracted from Ericaceae species, displayed significant protective effect on the rotenone (Rot)-induced mitochondrial dysfunction and apoptosis of human neuroblastoma cell (SH-SY5Y). We further found that the neuroprotective effect of Arb was associated with ameliorating oxidative stress, stabilizing of mitochondrial membrane potential, and enhancing adenosine triphosphate production. To investigate the underlying mechanism, we checked the AMP-activated protein kinase and autophagy pathway and we found that both were involved in the neuroprotection of Arb. Moreover, we explored the protective effect of Arb in drosophila PD model and found that Arb rescued parkin deficiency-induced motor function disability and mitochondrial abnormality of drosophila. Taken together, our study demonstrated that Arb got excellent neuroprotective effect on PD models both in vitro and in vivo and Arb might serve as a potent therapeutic agent for the treatment of PD.


Assuntos
Antioxidantes/uso terapêutico , Arbutina/uso terapêutico , Ericaceae/química , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Fitoterapia , Extratos Vegetais/química , Trifosfato de Adenosina/biossíntese , Adenilato Quinase/metabolismo , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Arbutina/isolamento & purificação , Arbutina/farmacologia , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/genética , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/fisiologia , Neuroblastoma/patologia , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/metabolismo , Transtornos Parkinsonianos/tratamento farmacológico , Rotenona/toxicidade , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética
8.
Adv Healthc Mater ; 8(14): e1900212, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31081268

RESUMO

Organelle-targeted photosensitizers have been reported to be effective cell apoptosis agents. Mitochondria is recognized as an ideal target for cancer treatment due to its central role in oxidative metabolism and apoptosis. Meanwhile, two-photon (TP) fluorescence microscopy has become a powerful tool for fluorescence imaging in biological events based on its minimizing photodamage/photobleaching and intrinsic 3D resolution in deep tissues and in vivo. In this study, a series of novel mitochondrial-targeted TP fluorescent photosensitizers (TP-tracers) are designed, synthesized, and systematically investigated. These TP-tracers exhibit extraordinary anti-interference capability among different cations, anions, and amino acids as well as the insensitivity to the changes of pH and complex biological environments. TP-tracers are further used in fluorescence living cells, Drosophila brains, and zebrafish imaging with low cytotoxicity, excellent mitochondria-targeting, and TP properties. The results demonstrate efficient mitochondria-targeting cell selective apoptosis based on TP-activated cancer cells with highly single cell selectivity, and the pharmacokinetic study reveals that MitoY2 does not have accumulation in rats. It is believed that these molecules hold great potential in TP-related smart phototherapy.


Assuntos
Apoptose/efeitos dos fármacos , Mitocôndrias/metabolismo , Fótons , Fármacos Fotossensibilizantes/farmacologia , Animais , Drosophila , Fluorescência , Células Hep G2 , Humanos , Masculino , Mitocôndrias/efeitos dos fármacos , Ratos Sprague-Dawley , Peixe-Zebra
9.
Front Aging Neurosci ; 10: 246, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30233351

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease, affecting about 7-10 million patients worldwide. The major pathological features of PD include loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) of the midbrain and the presence of α-synuclein-enriched Lewy bodies. Although the mechanism underlying PD pathogenesis remains to be elucidated, oxidative stress induced by the overproduction of reactive oxygen species (ROS) is widely accepted to be a key pathogenic factors. ROS cause oxidative damage to proteins, lipids, and DNA, which subsequently lead to neurodegeneration. Great efforts have been made to slow or stop the progress of PD. Unfortunately there is no effective cure for PD till now. Compounds with good antioxidant activity represent the promising candidates for therapeutics of PD. Some natural molecules from Chinese herbs are found to have good antioxidant activity. Both in vitro and in vivo studies demonstrate that these natural molecules could mitigate the oxidative stress and rescue the neuronal cell death in PD models. In present review, we summarized the reported natural molecules that displayed protective effects in PD. We also addressed the possible signal pathway through which natural molecules achieved their antioxidative effects and mitigate PD phenotypes. Hopefully it will pave the way to better recognize and utilize Chinese herbs for the treatment of PD.

10.
J Biosci Bioeng ; 126(6): 723-729, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29958771

RESUMO

Microalgae are recognized as promising producers of many bioactive products, but their utility is limited due to high production costs. We subjected the marine diatom Odontella aurita to three nitrogen supply regimes [initial low nitrogen (ILN), initial high nitrogen (IHN), and initial high nitrogen plus supplementary nitrogen (SN)] to investigate the accumulation of three high-value bioactive components: fucoxanthin, chrysolaminarin and eicosapentaenoic acid (EPA). We found that SN conditions maximized fucoxanthin accumulation: a maximum productivity of 6.01 mg L-1 d-1 was obtained, a 4.32-fold and 1.42-fold increase over production in the ILN and IHN groups, respectively. After nitrogen was depleted in the growth medium, chrysolaminarin became the dominant energy storage compound. Chrysolaminarin content rose to 60.33% of dry weight (DW) in the ILN group, and 46.27% of DW in the IHN group. Variations in fatty acid composition across the different nitrogen supply regimes indicated that EPA primarily accumulated in the glycolipids, especially when nitrogen supply was sufficient. The maximum productivity of chrysolaminarin (161.55 mg L-1 d-1) and EPA (9.37 mg L-1 d-1) was observed in the IHN group. However, IHN conditions did not maximize overall content of either compound. Our results demonstrated that O. aurita is potentially useful as a producer of a variety of bioactive products; the compounds produced by this species can be controlled by altering the nitrogen supply.


Assuntos
Diatomáceas/efeitos dos fármacos , Diatomáceas/metabolismo , Ácido Eicosapentaenoico/metabolismo , Nitrogênio/farmacologia , Xantofilas/metabolismo , beta-Glucanas/metabolismo , Técnicas de Cultura de Células/métodos , Meios de Cultura/química , Meios de Cultura/farmacologia , Relação Dose-Resposta a Droga , Ácido Eicosapentaenoico/análogos & derivados , Glicolipídeos/metabolismo , Microalgas/crescimento & desenvolvimento
11.
Neuromolecular Med ; 19(2-3): 375-386, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28695462

RESUMO

Exposure to divalent metals such as iron and manganese is thought to increase the risk for Parkinson's disease (PD). Under normal circumstances, cellular iron and manganese uptake is regulated by the divalent metal transporter 1 (DMT1). Accordingly, alterations in DMT1 levels may underlie the abnormal accumulation of metal ions and thereby disease pathogenesis. Here, we have generated transgenic mice overexpressing DMT1 under the direction of a mouse prion promoter and demonstrated its robust expression in several regions of the brain. When fed with iron-supplemented diet, DMT1-expressing mice exhibit rather selective accumulation of iron in the substantia nigra, which is the principal region affected in human PD cases, but otherwise appear normal. Alongside this, the expression of Parkin is also enhanced, likely as a neuroprotective response, which may explain the lack of phenotype in these mice. When DMT1 is overexpressed against a Parkin null background, the double-mutant mice similarly resisted a disease phenotype even when fed with iron- or manganese-supplemented diet. However, these mice exhibit greater vulnerability toward 6-hydroxydopamine-induced neurotoxicity. Taken together, our results suggest that iron accumulation alone is not sufficient to cause neurodegeneration and that multiple hits are required to promote PD.


Assuntos
Proteínas de Transporte de Cátions/fisiologia , Ferro/metabolismo , Transtornos Parkinsonianos/metabolismo , Substância Negra/metabolismo , Ubiquitina-Proteína Ligases/biossíntese , Animais , Proteínas de Transporte de Cátions/deficiência , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica , Ferro/toxicidade , Macaca fascicularis/genética , Manganês/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Oxidopamina/toxicidade , Transtornos Parkinsonianos/induzido quimicamente , Príons/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes/metabolismo , Teste de Desempenho do Rota-Rod , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética
12.
Bioresour Technol ; 172: 143-149, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25255191

RESUMO

Energy-intensive chemical conversion of crude algal oils into biodiesel is a major barrier for cost-effective algal biofuel production. To overcome this problem, we developed an enzyme-based platform for conversion of crude algal oils into fatty acid methyl esters. Crude algal oils were extracted from the oleaginous microalga Nannochloropsis oceanica IMET1 and converted by an immobilized lipase from Candida antarctica. The effects of different acyl acceptors, t-butanol as a co-solvent, oil to t-butanol ratio, oil to methanol ratio, temperature and reaction time on biodiesel conversion efficiency were studied. The conversion efficiency reached 99.1% when the conversion conditions were optimized, i.e., an oil to t-butanol weight ratio of 1:1, an oil to methanol molar ratio of 1:12, and a reaction time of 4h at 25°C. The enzymatic conversion process developed in this study may hold a promise for low energy consumption, low wastewater-discharge biochemical conversion of algal feedstocks into biofuels.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Eucariotos/metabolismo , Lipase/metabolismo , Petróleo/metabolismo , Estabilidade Enzimática , Eucariotos/enzimologia , Eucariotos/crescimento & desenvolvimento , Lipídeos/biossíntese , Metanol/metabolismo , Plantas/metabolismo , Temperatura , Fatores de Tempo
13.
Int J Mol Sci ; 15(7): 12778-90, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25046749

RESUMO

Gallbladder cancer is the most common malignancy of the bile duct, with low 5-year survival rate and poor prognosis. Novel effective treatments are urgently needed for the therapy of this disease. Here, we showed that cordycepin, the bioactive compound in genus Cordyceps, induced growth inhibition and apoptosis in cultured gallbladder cancer cells (Mz-ChA-1, QBC939 and GBC-SD lines). We found that cordycepin inhibited mTOR complex 1 (mTORC1) activation and down-regulated multiple drug resistant (MDR)/hypoxia-inducible factor 1α (HIF-1α) expression through activating of AMP-activated protein kinase (AMPK) signaling in gallbladder cancer GBC-SD cells. Contrarily, AMPKα1-shRNA depletion dramatically inhibited cordycepin-induced molecular changes as well as GBC-SD cell apoptosis. Further, our results showed that co-treatment with a low concentration cordycepin could remarkably enhance the chemosensitivity of GBC-SD cells to gemcitabine and 5-fluorouracil (5-FU), and the mechanism may be attributed to AMPK activation and MDR degradation. In summary, cordycepin induces growth inhibition and apoptosis in gallbladder cancer cells via activating AMPK signaling. Cordycepin could be a promising new drug or chemo-adjuvant for gallbladder cancer.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antineoplásicos/farmacologia , Desoxiadenosinas/farmacologia , Neoplasias da Vesícula Biliar/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Complexos Multiproteicos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Alvo Mecanístico do Complexo 1 de Rapamicina , Transdução de Sinais , Gencitabina
14.
Bioresour Technol ; 110: 496-502, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22326335

RESUMO

Flocculation induced by pH increase for harvesting microalgae and reuse of flocculated medium were evaluated. Increasing the medium pH value induced the highest flocculation efficiency of up to 90% for freshwater microalgae (Chlorella vulgaris, Scenedesmus sp., Chlorococcum sp.) with low/medium biomass concentrations and marine microalgae (Nannochloropsis oculata, Phaeodactylum tricornutum). The mechanism may be explained that Mg(2+) in the growth medium hydrolyzed to form magnesium hydroxide precipitate, which coagulated microalgal cells by sweeping flocculation and charge neutralization. Additionally, this study revealed that the microalgal biomass concentrations and released polysaccharide (RPS) from microalgae could influence the flocculation efficiencies. Furthermore, neutralizing pH and then supplementing nutrients allowed the flocculated medium to maintain an approximate growth yield to that of the fresh medium in algal cultivation. These results suggest that the method presented here is effective, and allows the reuse of the flocculated medium, thereby contributing to the economic production from algae to biodiesel.


Assuntos
Floculação , Concentração de Íons de Hidrogênio , Microalgas/metabolismo , Meios de Cultura
15.
Hepatobiliary Pancreat Dis Int ; 1(1): 146-9, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14607646

RESUMO

OBJECTIVE: To observe the role and the timing of EN in the treatment of patients with severe acute pancreatitis (SAP). METHODS: Eleven patients with severe acute pancreatitis underwent systemic nutrition support were studied. EN was given through jejunostomy tube (or Bengmark tube) after a period of PN maintenance. EN started when serum and urine amylase activity returned to normal with regular peristaltic sound, defecation or break wind. The sequence of preparation was as follows: saline glucose-->chemically defined diet-->polymeric diet-->normal diet. RESULTS: In all the patients, none died. The rate of late complications was lower, and the levels of serum albumin and transferritin significantly increased in the post-EN period as compared with the pre-EN period, although the count of lymphocytes was less changed. CONCLUSIONS: Nutritional support should be transformed from PN to EN as early as possible during the treatment of patients with severe acute pancreatitis. EN could not only continue sufficient nutritional support, but also avoid the unfavorable effects of long-time PN, thus reducing complications as well as mortality.


Assuntos
Nutrição Enteral , Pancreatite/dietoterapia , Doença Aguda , Adulto , Idoso , Feminino , Humanos , Jejunostomia , Masculino , Pessoa de Meia-Idade , Prognóstico , Albumina Sérica , Índice de Gravidade de Doença , Transferrina/metabolismo
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