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3.
World J Cardiol ; 15(10): 508-517, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37900904

RESUMO

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is a leading cause of death worldwide. AIM: To explore factors influencing prehospital return of spontaneous circulation (P-ROSC) in patients with OHCA and develop a nomogram prediction model. METHODS: Clinical data of patients with OHCA in Shenzhen, China, from January 2012 to December 2019 were retrospectively analyzed. Least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression were applied to select the optimal factors predicting P-ROSC in patients with OHCA. A nomogram prediction model was established based on these influencing factors. Discrimination and calibration were assessed using receiver operating characteristic (ROC) and calibration curves. Decision curve analysis (DCA) was used to evaluate the model's clinical utility. RESULTS: Among the included 2685 patients with OHCA, the P-ROSC incidence was 5.8%. LASSO and multivariate logistic regression analyses showed that age, bystander cardiopulmonary resuscitation (CPR), initial rhythm, CPR duration, ventilation mode, and pathogenesis were independent factors influencing P-ROSC in these patients. The area under the ROC was 0.963. The calibration plot demonstrated that the predicted P-ROSC model was concordant with the actual P-ROSC. The good clinical usability of the prediction model was confirmed using DCA. CONCLUSION: The nomogram prediction model could effectively predict the probability of P-ROSC in patients with OHCA.

4.
Huan Jing Ke Xue ; 43(10): 4502-4510, 2022 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-36224136

RESUMO

The "bacteria-algae" system plays an important role in water ecosystems. The effects of bacteria in phycospheres on the growth of Microcystis aeruginosa under in-situ nutrient stimulation were studied to explore the bacteria-algae interaction during a cyanobacteria bloom. The results showed that LB medium could inhibit the growth of M. aeruginosa, and the algicidal rate was 86.49%. Sodium acetate, glucose, and sodium citrate could promote M. aeruginosa, and the growth rate was more than 50%. The addition of nutrients in M. aeruginosa could have changed the biocoenosis in the phycosphere and increased the species richness by 16S rRNA gene sequencing, and the number of bacteria in the phycosphere increased dramatically in the LB medium and peptone groups. The physiological and biochemical responses showed that algae suffered serious lipid peroxidation, and superoxide dismutase (SOD) and catalase (CAT) activities first increased significantly and subsequently decreased under the oxidative stress of LB medium or peptone. Scanning electron microscopy (SEM) indicated that the surface of algae cells appeared wrinkled, invaded, and atrophied under LB medium stimulation, whereas bacteria in the phycosphere significantly increased. Furthermore, six strains of algicidal bacteria were isolated from the LB medium and peptone groups, and the algicidal rate of Bacillus sp. A1 was 97.55%, which confirmed that the phycosphere of M. aeruginosa included algicidal bacteria. Therefore, appropriate external nutrient stimulation can produce algicidal bacteria in situ to prevent cyanobacterial blooms.


Assuntos
Microcystis , Antioxidantes , Catalase , Ecossistema , Glucose , Proliferação Nociva de Algas , Nutrientes , Peptonas/farmacologia , RNA Ribossômico 16S/genética , Acetato de Sódio/farmacologia , Citrato de Sódio/farmacologia , Superóxido Dismutase , Água
5.
J Oncol ; 2022: 8656865, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432534

RESUMO

The goal of this study was to investigate the homeobox (HOX) gene expression status and its prognostic value in glioblastoma multiforme (GBM) and to uncover the biological processes related to its expression. The prognostic value of HOX genes in GBM was systematically investigated by a genome-wide analysis of HOX gene expression profiles in GBM patient samples in The Cancer Genome Atlas (TCGA) project (microarray dataset) and validation datasets. Using the differentially expressed gene (DEG) analysis and a Cox regression model, we discovered that the HOXC6 could stratify patients into significantly different survival (p = 0.0012, log-rank test) groups in the training cohort. TCGA RNA-seq and GSE16011 datasets were used for validation. Multivariate Cox and stratification analysis indicated that HOXC6 was an independent prognostic factor after adjusting for other clinical covariates. Bioinformatic analysis suggested that the HOXC6 might be involved in the cell cycle-related biological processes and pathways that are well established in the context of glioblastoma tumorigenesis. We further explored the bioinformatic implications by gene set enrichment analysis (GSEA). Tumor cell biology experiments verified the role of HOXC6 in proliferation and cell cycle progression. In conclusion, HOXC6 might be a candidate biomarker gene for individual treatment optimization of glioblastoma. HOXC6 expression has a significant prognostic value and is related to the cell cycle process in glioblastoma.

6.
Neoplasma ; 69(1): 242-250, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35014536

RESUMO

The number of circulating endothelial progenitor cells (EPCs) was found to increase in patients with breast cancer, but the alteration in EPC function remains to be elusive. We conducted this study to evaluate the number and function of peripheral EPCs of breast cancer patients and its possible underlying mechanism. Besides, the vascular endothelial growth factor (VEGF), VCAM-1, IL-6, and IL-34 levels were measured in blood samples and also in vitro in a medium of EPCs. We found that the number of circulating EPCs in breast cancer patients was significantly higher than that in normal control and remarkably augmented in a stage-dependent manner. Meanwhile, a similar enhancement was observed in the migratory, proliferative, and adhesive activity of circulating EPCs originating from breast cancer patients. More importantly, the VEGF level in blood samples was dramatically elevated in comparison to the control, which was correlated positively with the number and activity of circulating EPCs from breast cancer patients. Moreover, in vitro medium of EPCs from breast cancer patients highly expressed VEGF compared with that from the control, which also had a positive correlation with the number and activity of circulating EPCs from breast cancer patients. This is the first time to demonstrate that the number and function of circulating EPCs are promoted in breast cancer patients, which are positively related to an enhanced VEGF production. These may provide a novel target for improving the outcome of breast cancer.


Assuntos
Neoplasias da Mama , Células Progenitoras Endoteliais , Feminino , Humanos , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
7.
Theranostics ; 11(3): 1059-1078, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33391521

RESUMO

Emerging clinical and experimental evidence demonstrates that neuroinflammation plays an important role in cognitive impairment associated with neuropathic pain. However, how peripheral nerve challenge induces remote inflammation in the brain remains largely unknown. Methods: The circulating leukocytes and plasma C-X-C motif chemokine 12 (CXCL12) and brain perivascular macrophages (PVMs) were analyzed by flow cytometry, Western blotting, ELISA, and immunostaining in spared nerve injury (SNI) mice. The memory function was evaluated with a novel object recognition test (NORT) in mice and with Montreal Cognitive Assessment (MoCA) in chronic pain patients. Results: The classical monocytes and CXCL12 in the blood, PVMs in the perivascular space, and gliosis in the brain, particularly in the hippocampus, were persistently increased following SNI in mice. Using the transgenic CCR2RFP/+ and CX3CR1GFP/+ mice, we discovered that at least some of the PVMs were recruited from circulating monocytes. The SNI-induced increase in hippocampal PVMs, gliosis, and memory decline were substantially prevented by either depleting circulating monocytes via intravenous injection of clodronate liposomes or blockade of CXCL12-CXCR4 signaling. On the contrary, intravenous injection of CXCL12 at a pathological concentration in naïve mice mimicked SNI effects. Significantly, we found that circulating monocytes and plasma CXCL12 were elevated in chronic pain patients, and both of them were closely correlated with memory decline. Conclusion: CXCL12-mediated monocyte recruitment into the perivascular space is critical for neuroinflammation and the resultant cognitive impairment in neuropathic pain.


Assuntos
Quimiocina CXCL12/metabolismo , Sistema Glinfático/metabolismo , Inflamação/metabolismo , Transtornos da Memória/metabolismo , Monócitos/metabolismo , Neuralgia/metabolismo , Neurônios/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Sistema Glinfático/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Inflamação/patologia , Masculino , Transtornos da Memória/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/patologia , Neuralgia/patologia , Neurônios/patologia , Traumatismos dos Nervos Periféricos/metabolismo , Traumatismos dos Nervos Periféricos/patologia , Receptores CXCR4/metabolismo
8.
J Spinal Cord Med ; 42(3): 355-359, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-29920172

RESUMO

CONTEXT/OBJECTIVE: Following acute spinal cord injury (ASCI) in rabbits, subarachnoid space injection of Danshen was performed to protect the neurological damage. In this study, we established rabbit models of spinal cord injury using a modified Allen's method. DESIGN: After the operation introducing the injuries, the rabbits were randomized into two different groups, control group (normal saline, NS) and Danshen, a component extracted from Chinese herb, treatment group. Each rabbit was supplied with either the drug or placebo at 0.3 ml/kg each day through subarachnoid cavity. SETTING: Rabbit model of acute spinal cord injury were used for the response to Danshen treatment. PARTICIPANTS: Total 48 Chinese rabbits aged four∼ five months old provided by Experimental Animal Center of Hubei Province were used for this study. INTERVENTIONS: Danshen drug or placebo was administered via a silicon tube embedded under the spinal dura mater to administer the drugs into subarachnoid cavity. OUTCOME MEASURES: After the treatment, damage indicators including cell apoptosis, morphological changes and oxidative damages were assessed. RESULTS: We found out that cell apoptosis was decreased after Danshen injection as determined by downregulation of apoptosis index (AI) by TUNEL analysis as well as propidium iodide (PI) percentage by FACS analysis. In the meanwhile, we observed cells after the treatment have increased numbers of BCL-2 positive cells, this indicated the antiapoptotic gene expression is increased after Danshen treatment. When we check the oxidative damage indicators, we found superoxide dismutase (SOD) was increased and malondiadehyde (MDA) levels were decreased after the treatment. CONCLUSION: Danshen can protect ASCI through inhibition of oxidative damage in the injured cells and thus reduce the subsequent cell apoptosis in the spinal.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Traumatismos da Medula Espinal/patologia , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Estresse Oxidativo/efeitos dos fármacos , Coelhos , Distribuição Aleatória , Salvia miltiorrhiza , Espaço Subaracnóideo
9.
J Cancer Res Clin Oncol ; 143(6): 991-1004, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28285404

RESUMO

BACKGROUND: ZFAS1 is a newly identified long noncoding RNA (lncRNA) that promotes tumor growth and metastasis. Exosomes mediate cellular communications in cancer by transmitting active molecules. The presence of ZFAS1 in the circulating exosomes and the roles of exosomal ZFAS1 in gastric cancer (GC) remains unknown. The aim of this study was to investigate the potential roles of exosomal ZFAS1 in GC. METHODS: The expression of ZFAS1 was examined in the tumor tissues, serum samples, serum exosomes of GC patients and cell lines using qRT-PCR. The correlation between ZFAS1 expression and the clinicopathological characteristics was analyzed. The characteristics of exosomes were identified using transmission electron microscope (TEM), Nanoparticle Tracking Analysis (NTA), and western blot. The biological roles of ZFAS1 in GC cell growth and mobility were investigated using cell counting, cell colony formation, and transwell migration assay. The potential mechanism of ZFAS1 was demonstrated using flow cytometry, western blot, and qRT-PCR. RESULTS: ZFAS1 expression was elevated in GC cells, tumor tissues, serum and serum exosomes of GC patients. The increased ZFAS1 expression was significantly correlated with lymphatic metastasis and TNM stage. ZFAS1 knockdown inhibited the proliferation and migration of GC cells by suppressing cell cycle progression, inducing apoptosis, and inhibiting epithelial-mesenchymal transition (EMT). On the contrary, ZFAS1 overexpression promoted the proliferation and migration of GC cells. Moreover, ZFAS1 was present in exosomes and could be transmitted by exosomes to enhance GC cell proliferation and migration. CONCLUSION: ZFAS1 could be delivered by exosomes to promote GC progression, which suggests that ZFAS1 may serve as a potential diagnostic and prognostic biomarker for GC.


Assuntos
Exossomos/fisiologia , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Exossomos/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Transporte de RNA/fisiologia , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Células Tumorais Cultivadas
10.
Ying Yong Sheng Tai Xue Bao ; 26(6): 1871-6, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26572044

RESUMO

The accumulation of Cd2+ and Hg2+ in Phascolosoma esculenta and its effects on its growth and main nutrient components were investigated using atomic absorption spectrometer analysis and atomic fluorescence spectrometer examination. The results showed that within the experimental heavy metal concentrations, the amounts of Cd2+ and Hg2+ accumulated in the somatic muscles increased with increasing exposure time and reached their saturated levels at the end of the experiment. Exposure of higher heavy metal concentrations speeded up the accumulation of Cd2+ and Hg2+ and subsequently took less time to reach their saturated levels, which were greater than those of lower concentration groups. The rate of mass gain of P. esculenta decreased with increasing the heavy metal exposure concentrations. The combination exposure of Cd2+ and Hg2+ led to a significantly lower mass gain rate compared to those exposed to Cd2+ or Hg2+. The protein content of somatic muscles increased with the increase of exposure concentration and reached the maximum values at 0.05 and 0.02 mg · L(-1) for Cd2+ and Hg2+, respectively. After that, the protein content of somatic muscles began to decrease. The combined exposure of the two heavy metals showed similar effect trends but more significant impacts on the protein content of somatic muscles. The lipid content of somatic muscles decreased with increasing the concentration of Cd2+ or Hg2+ exposure, and the combination of Cd2+ and Hg2+ led to lower lipid content.


Assuntos
Cádmio/química , Mercúrio/química , Poliquetos/química , Animais , Metais Pesados/química , Músculos/química , Espectrometria de Fluorescência , Espectrofotometria Atômica
11.
Biochem Pharmacol ; 85(6): 772-9, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23178656

RESUMO

Hyperacute rejection (HAR) is a main barrier in xenotransplantation, which is mediated by the combination of natural antibody to the xenograft and complement activation. Current therapies have focus on the inhibition of complement by development of complement inhibitor and transgenic animal organ. Here, we investigated the effects of rFII, a recombinant fibrinogenase from Agkistrodon acutus venom, on complement and HAR. The degradation effect of rFII on complement was tested by SDS-PAGE, CH50 examination, ELISA Kit and cofocal immunofluorescence microscopy in vitro and in vivo. An ex-vivo rat-to-human perfusion model and a vivo guinea-pig-to-rat heat HAR model were used to determine the protection of rFII against HAR. Our investigation indicated that rFII could significantly degrade human C5, C6, and C9, decrease the activity of complement, and inhibit the MAC deposition on HUVECs membrane in vitro. In addition, serum levels of C1q, C3 and C4 in rat were gradually reduced after infusion of rFII. Importantly, in an ex vivo rat-to-human perfusion model, the survival of rat hearts perfused with human serum treated with rFII (83.36 ± 16.63 min) were significantly longer than that of hearts perfused with fresh human serum(15.94 ± 4.75 min). At the time of 15 minutes after perfusion, functions of hearts added with 50 ug/ml rFII sustained well with heart rates at 283 ± 65.32 beats/minute and LVDP at 13.70 ± 5.45 Kpa, while that of hearts perfused with fresh human serum were severely damaged by HAR with heart rates at 107.77 ± 40.31 beats/minute and LVDP at 1.01 ± 0.83 Kpa. We also found that rFII significantly decreased the levels of C1q, C3 and C4 in human fresh serum perfusate. In a vivo guinea-pig-to-rat heat HAR model, the survival of rat hearts treated with rFII were significantly longer than that of hearts perfused with normal saline; and relieved heart damage by complete activation. Our finding demonstrates the anti-complement property of rFII and its protection against HAR, indicating that rFII might be as a potential therapeutic agent for xenotransplantation.


Assuntos
Proteínas do Sistema Complemento/metabolismo , Venenos de Crotalídeos/enzimologia , Venenos de Crotalídeos/farmacologia , Rejeição de Enxerto/prevenção & controle , Metaloendopeptidases/farmacologia , Animais , Cobaias , Transplante de Coração , Hemólise , Imuno-Histoquímica , Microscopia de Fluorescência , Proteólise , Ratos , Proteínas Recombinantes/farmacologia
12.
Chin Med J (Engl) ; 125(11): 1908-14, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22884052

RESUMO

BACKGROUND: Anxiety and fear frequently causes an aversion to applying a face mask and increases difficulty during pediatric induction. There is at present little study of this problem. Therefore, the aim of this study was to investigate the effect of the combination of mask preconditioning and midazolam pretreatment on mask acceptance during pediatric induction and on postoperative mask fear. METHODS: One hundred and sixty children were randomly assigned into four groups: the mask preconditioning group (MaG), the midazolam pretreatment group (MiG), the mask/midazolam combination group (Ma/MiG), and the saline group (SaG). The Modified Yale Preoperative Anxiety Scale (m-YPAS) was employed to assess the anxiety in the operation room (OR). A Mask Acceptance Score (MAS) was measured during inhalational induction and the incidence of mask fear (MAS ≤ 2) was evaluated postoperatively. RESULTS: The MaG and Ma/MiG groups had the highest mask acceptance scores but there were no differences between these two groups (P < 0.05). The average anxiety level of children entering the OR was much lower in the MaG and Ma/MiG groups than in the SaG group (P < 0.05). During induction, the anxiety level increased in the SaG and MaG groups but decreased in the MiG and Ma/MiG groups (P < 0.05). At the postoperative third day, the incidence of mask fears was as high as 23% in the SaG group, 15% in the MiG group, but only 2.5% in the MaG and Ma/MiG groups. CONCLUSIONS: The single use of mask preconditioning has a better influence than midazolam for increasing mask acceptance during inhalational induction and reducing postoperative mask fear, reducing the anxiety level during induction, improving induction compliance and shortening the total mask time. A mask preconditioning and midazolam combination did not increase mask acceptance during inhalational induction, reduce mask fears postoperatively, improve induction compliance, nor shorten the total mask time. But it can better reduce the anxiety level during induction.


Assuntos
Ansiedade/prevenção & controle , Medo/efeitos dos fármacos , Máscaras , Midazolam/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Masculino
13.
Biochem Pharmacol ; 84(7): 905-13, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22728069

RESUMO

The incidence of disseminated intravascular coagulation (DIC), which leads to multiple organ dysfunction and high mortality, has remained constant in recent years. At present, treatments of DIC have focused on preventing cytokine induction, inhibiting coagulation processes and promoting fibrinolysis. Recent clinical trials have supported the use of antithrombin and activated protein C supplementation in DIC. To better understand the mechanism of treatment on DIC, we here report a novel fibrinogenase from Agkistrodon acutus (FIIa) that effectively protected against LPS-induced DIC in a rabbit model, and detected the tissue factors expression in HUVE cells after using FIIa. In vivo, administration of FIIa reduced hepatic and renal damage, increased the concentration of fibrinogen, the activities of protein C, the platelet count, APTT, PT, FDP, the level of AT-III and t-PA, decreased the level of PAI-1, and increased survival rate in LPS-induced DIC rabbits. In vitro experiments, we further confirmed that FIIa up-regulated the expression of t-PA and u-PA, down-regulated the expression of PAI-1, and directly activated protein C. Our findings suggest that FIIa could effectively protect against DIC via direct degradation of microthrombi and activation of protein C as well as provide a novel strategy to develop a single proteinase molecule for targeting the main pathological processes of this disease.


Assuntos
Agkistrodon/fisiologia , Venenos de Crotalídeos/enzimologia , Coagulação Intravascular Disseminada/tratamento farmacológico , Proteína C/metabolismo , Serina Endopeptidases/metabolismo , Trombose/metabolismo , Animais , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Coagulação Intravascular Disseminada/induzido quimicamente , Coagulação Intravascular Disseminada/prevenção & controle , Células Endoteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Nefropatias/induzido quimicamente , Nefropatias/tratamento farmacológico , Nefropatias/prevenção & controle , Lipopolissacarídeos/toxicidade , Masculino , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Proteína C/genética , Coelhos , Serina Endopeptidases/farmacologia , Serina Endopeptidases/uso terapêutico , Trombose/tratamento farmacológico , Ativador de Plasminogênio Tecidual/efeitos dos fármacos , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/efeitos dos fármacos , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
14.
J Mater Sci Mater Med ; 23(8): 1921-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22580754

RESUMO

Histidine-hyaluronic acid (His-HA) conjugates were synthesized using hyaluronic acid (HA) as a hydrophilic segment and histidine (His) as hydrophobic segment by 1-ethyl-3(3-dimethylaminopropyl)carbodiimide (EDC) mediated coupling reactions. The structural characteristics of the His-HA conjugates were investigated using (1)H NMR. His-HA nanoparticles (HH-NPs) were prepared based on His-HA conjugates, and the characteristics of HH-NPs were investigated using dynamic light scattering, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and fluorescence spectroscopy. The particles were between 342 and 732 nm in size, depending on the degree of substitution (DS) of the His. TEM and SEM images indicated that the morphology of HH-NPs was spherical in shape. The critical aggregation concentrations of HH-NPs ranged from 0.034 to 0.125 mg/ml, which decreased with an increase in the DS of the His. Images of fluorescence microscopy indicate that HH-NPs were taken up by the cancer cell line (MCF-7), and significantly decreased by competition inhibition of free HA. From the cytotoxicity test, it was found that DOX-loaded HH-NPs exhibited similar dose and time-dependent cytotoxicity against MCF-7 cells with free DOX.


Assuntos
Neoplasias da Mama/metabolismo , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Portadores de Fármacos/síntese química , Ácido Hialurônico/química , Nanocápsulas/química , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/síntese química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Histidina , Humanos
15.
J Agric Food Chem ; 59(5): 1962-7, 2011 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-21288023

RESUMO

Hydrophobic alginate derivative was prepared by modification of alginate by acid chloride reaction using oleoyl chloride without organic solvents. The conjugate of oleoyl alginate ester (OAE) was confirmed by FT-IR and (1)H NMR. The degree of substitution (DS) of OAE was determined by (1)H NMR, and it ranged from 0.84 to 3.85. In distilled water, OAE formed self-assembled nanoparticles at low concentrations in aqueous medium, and nanoparticles retained their structural integrity both in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF). The loading and release characteristics of nanoparticles based on OAE were investigated using vitamin D(3) as a model nutraceutical. As the concentration of vitamin D(3) increased, the loading capacity (LC) increased, whereas the loading efficiency (LE) decreased. Nanoparticles could release vitamin D(3) at a sustained rate in gastrointestinal fluid. These results revealed the potential of OAE nanoparticles as oral carriers for sustained release of vitamin D(3).


Assuntos
Alginatos/química , Colecalciferol/administração & dosagem , Portadores de Fármacos/síntese química , Nanopartículas/química , Preparações de Ação Retardada , Trato Gastrointestinal/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Ácidos Oleicos/química , Espectroscopia de Infravermelho com Transformada de Fourier
16.
World J Gastroenterol ; 6(3): 377-380, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11819602

RESUMO

AIM:To construct the recombinant of HDV cDNA and HBV specific ribozyme gene by recombinant PCR in order to use HDV as a transporting vector carrying HBV-specific ribozyme into liver cells for inhibiting the replication of HBV.METHODS:We separately cloned the ribozyme (RZ) gene and recombinant DVRZ (comprising HDV cDNA and HBV-specific ribozyme gene) into the downstream of T7 promoter of pTAdv-T vector and studied the in vitro cleavage activity of their transcripts (rRZ, rDVRZ) on target RNA (rBVCF) from in vitro transcription of HBV C gene fragment(BVCF).RESULTS:Both the simple (rRZ) and the recombinant ribozyme rDVRZ could efficiently catalyze the cleavage of target RNA (rBVCF) under different temperatures (37°, 42° and 55°) and Mg(2+) concentrations (10mmol/L, 15mmol/L and 20mmol/L) and their catalytic activity tended to increase as the temperature was rising. But the activity of rRZ was evidently higher than that of rDVRZ.CONCLUSION:The recombinant of HDV cDNA and ribozyme gene had the potential of being further explored and used in gene therapy of HBV infection.

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