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In the treatment of bowel diseases such as ulcerative colitis through oral administration, an effective drug delivery system targeting the colon is crucial for enhancing efficacy and minimizing side effects of therapeutic agents. This study focuses on the development of a novel nanocomposite hydrogel bead comprising a synergistic blend of biological macromolecules, namely sodium alginate (ALG) and hyaluronic acid (HA), reinforced with layered double hydroxide nanoparticles (LDHs) for the oral delivery of dual therapeutics. The synthesized hydrogel bead exhibits significantly enhanced gel strength and controllable release of methylprednisolone (MP) and curcumin (CUR), serving as an anti-inflammatory drug and a mucosal healing agent, compared to native ALG or ALG/HA hydrogel beads without LDHs. The physicochemical properties of the synthesized LDHs and hydrogel beads were characterized using various techniques, including scanning electron microscopy, zeta potential measurement, transmission electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. In vitro release studies of MP and CUR under simulated gastrointestinal tract (GIT) conditions demonstrate the superior controlled release property of the nanocomposite hydrogel bead, particularly in minimizing premature drug release in the upper GIT environment while sustaining release of over 82 % of drugs in the colonic environment. Thus, the modularly engineered carrier designed for oral colon targeting holds promise as a potential candidate for the treatment of ulcerative colitis.
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Alginatos , Liberação Controlada de Fármacos , Ácido Hialurônico , Hidrogéis , Nanopartículas , Alginatos/química , Ácido Hialurônico/química , Hidrogéis/química , Nanopartículas/química , Administração Oral , Portadores de Fármacos/química , Humanos , Hidróxidos/química , Curcumina/química , Curcumina/administração & dosagem , Curcumina/farmacologia , Metilprednisolona/química , Metilprednisolona/administração & dosagem , Sistemas de Liberação de Medicamentos , Colite Ulcerativa/tratamento farmacológicoRESUMO
The adsorption ability of hydrogen, hydroxide, and oxygenic intermediates plays a crucial role in electrochemical water splitting. Electron-deficient metal-active sites can prompt electrocatalytic activity by improving the adsorption ability of intermediates. However, it remains a significant challenge to synthesize highly abundant and stable electron-deficient metal-active site electrocatalysts. Herein, we present a general approach to synthesizing a hollow ternary metal fluoride (FeCoNiF2) nanoflake array as an efficient and robust bifunctional electrocatalyst for the hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). We find that the F anion withdraws electrons from the metal centers, inducing an electron-deficient metal center catalyst. The rationally designed hollow nanoflake array exhibits the overpotential of 30 mV for HER and 130 mV for UOR at a current density of 10 mA cm-2 and superior stability without decay events over 150 h at a large current density of up to 100 mA cm-2. Remarkably, the assembled urea electrolyzer using a bifunctional hollow FeCoNiF2 nanoflake array catalyst requires cell voltages of only 1.352 and 1.703 V to afford current densities of 10 and 100 mA cm-2, respectively, which are 116 mV less compared with that required for overall water splitting.
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Manganese dioxide nanomaterials have wide applications in many areas from catalysis and Li-ion batteries to gas sensing. Understanding the crystallization pathways, morphologies, and formation of defects in their structure is particularly important but still a challenging issue. Herein, we employed an arsenal of X-ray diffraction (XRD), scanning electron microscopy (SEM), neutron diffraction, positron annihilation spectroscopies, and ab initio calculations to investigate the evolution of the morphology and structure of α-MnO2 nanomaterials prepared via reduction of KMnO4 solution with C2H5OH prior to being annealed in air at 200-600 °C. We explored a novel evolution that α-MnO2 nucleation can be formed even at room temperature and gradually developed to α-MnO2 nanorods at above 500 °C. We also found the existence of H+ or K+ ions in the [1 × 1] tunnels of α-MnO2 and observed the simultaneous presence of Mn and O vacancies in α-MnO2 crystals at low temperatures. Increasing the temperature removed these O vacancies, leaving only the Mn vacancies in the samples.
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Perturbations in the gut microbiome have been associated with colorectal cancer (CRC), with the colonic overabundance of Fusobacterium nucleatum shown as the most consistent marker. Despite its significance in the promotion of CRC, genomic studies of Fusobacterium is limited. We enrolled 43 Vietnamese CRC patients and 25 participants with non-cancerous colorectal polyps to study the colonic microbiomes and genomic diversity of Fusobacterium in this population, using a combination of 16S rRNA gene profiling, anaerobic microbiology, and whole genome analysis. Oral bacteria, including F. nucleatum and Leptotrichia, were significantly more abundant in the tumour microbiomes. We obtained 53 Fusobacterium genomes, representing 26 strains, from the saliva, tumour and non-tumour tissues of six CRC patients. Isolates from the gut belonged to diverse F. nucleatum subspecies (nucleatum, animalis, vincentii, polymorphum) and a potential new subspecies of Fusobacterium periodonticum. The Fusobacterium population within each individual was distinct and in some cases diverse, with minimal intra-clonal variation. Phylogenetic analyses showed that within four individuals, tumour-associated Fusobacterium were clonal to those isolated from non-tumour tissues. Genes encoding major virulence factors (Fap2 and RadD) showed evidence of horizontal gene transfer. Our work provides a framework to understand the genomic diversity of Fusobacterium within the CRC patients, which can be exploited for the development of CRC diagnostic and therapeutic options targeting this oncobacterium.
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Neoplasias Colorretais , Microbiota , Humanos , RNA Ribossômico 16S/genética , Filogenia , Fusobacterium/genética , Genômica , Neoplasias Colorretais/microbiologia , Povo AsiáticoRESUMO
A combination of polyoxometalates with polypyrrole is introduced in this work. Our goal was to include phosphotungstic acid (PTA) in different molar concentrations (0.005, 0.01, and 0.05 M) in the electropolymerization of pyrrole doped with dodecylbenzene sulfonate (DBS) and phosphotungstinates (PT), forming PPy/DBS-PT films. Scanning electron microscopy (SEM) revealed that the PPy/DBS-PT films became denser and more compact with increasing PTA concentrations. The incorporation of PT in PPy/DBS was analyzed using Fourier-transform infrared (FTIR) and energy dispersive X-ray (EDX) spectroscopy. The linear actuation in cyclic voltammetry and potential square wave steps in an organic electrolyte revealed increasing mixed actuation, with major expansion upon oxidation found for PPy/DBS-PT films with a PTA concentration of 0.005 M. Best results of a strain of 12.8% and stress at 0.68 MPa were obtained for PPy/DBS-PT (0.01 M). The PPy/DBS-PT films polymerized in the presence of 0.05 M of PTA and showed main expansion upon reduction, changing the actuation direction. Chronopotentiometric measurements of PPy/DBS-PT samples were conducted to determine the specific capacitance optimal for a 0.01 M PTA concentration in the range of 80 F g-1 (±0.22 A g-1).
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A widely used herbicide for controlling weeds, glyphosate, is causing environmental pollution. It is necessary to remove it from environment using a cost-effective and eco-friendly method. The aims of this study were to isolate glyphosate-degrading bacteria and to optimize their degradative conditions required for bioremediation. Sixteen bacterial strains were isolated through enrichment and one strain, Rhodococcus soli G41, demonstrated a high removal rate of glyphosate than other strains. Response surface methodology was employed to optimize distinct environmental factors on glyphosate degradation of G41 strain. The optimal conditions for the maximum glyphosate degradation were found to have the NH4Cl concentration of 0.663% and glyphosate concentration of 0.115%, resulting in a maximum degradation of 42.7% after 7 days. Bioremediation analysis showed 47.1% and 40% of glyphosate in unsterile soil and sterile soil was removed by G41 strain after 14 days, respectively. The presence of soxB gene in G41 strain indicates that the glyphosate is degraded via the eco-friendly sarcosine pathway. The results indicated that G41 strain has the potential to serve as an in-situ candidate for bioremediation of glyphosate polluted environments.
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Herbicidas , Rhodococcus , Biodegradação Ambiental , Glicina/análogos & derivados , Herbicidas/metabolismo , Rhodococcus/genética , Rhodococcus/metabolismo , Solo , Microbiologia do Solo , GlifosatoRESUMO
Rheumatoid arthritis (RA), an autoimmune disease, is characterized by chronic joint inflammation and pain. We previously found that the deletion of T-cell death-associated gene 8 (TDAG8) significantly reduces disease severity and pain in RA mice. Whether it is by modulating gut microbiota remains unclear. In this study, 64 intestinal samples of feces, cecal content, and cecal mucus from the complete Freund's adjuvant-induced arthritis mouse models were compared. The α- and ß-diversity indices of the microbiome were significantly lower in RA mice. Cecal mucus showed a higher ratio of Firmicutes to Bacteroidetes in RA than healthy mice, suggesting the ratio could serve as an RA indicator. Four core genera, Eubacterium_Ventriosum, Alloprevotella, Rikenella, and Treponema, were reduced in content in both feces and mucus RA samples, and could serve microbial markers representing RA progression. TDAG8 deficiency decreased the abundance of proinflammation-related Eubacterium_Xylanophilum, Clostridia, Ruminococcus, Paraprevotella, and Rikenellaceae, which reduced local mucosal inflammation to relieve RA disease severity and pain. The pharmacological block of the TDAG8 function by a salicylanilide derivative partly restored the RA microbiome to a healthy composition. These findings provide a further understanding of specific bacteria interactions with host gut mucus in the RA model. The modulation by TDAG8 on particular bacteria can facilitate microbiota-based therapy.
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Artrite Reumatoide , Microbioma Gastrointestinal , Microbiota , Animais , Bactérias/genética , Microbioma Gastrointestinal/genética , Inflamação , Camundongos , Dor , SalicilanilidasRESUMO
Controllable linear actuation of polypyrrole (PPy) is the envisaged goal where only one ion dominates direction (here anions) in reversible redox cycles. PPy with polyethylene oxide (PEO) doped with dodecylbenzenesulfonate forms PPy-PEO/DBS films (PPy-PEO), which are applied in propylene carbonate (PC) solvent with electrolytes such as 1-ethyl-2,3-dimethylimidazolium trifluoromethanesulfonate (EDMICF3SO3), sodium perchlorate (NaClO4) and tetrabutylammonium hexafluorophosphate (TBAPF6) and compared in their linear actuation properties with pristine PPy/DBS samples. PPy-PEO showed for all applied electrolytes that only expansion at oxidation appeared in cyclic voltammetric studies, while pristine PPy/DBS had mixed-ion actuation in all electrolytes. The electrolyte TBAPF6-PC revealed for PPy-PEO best results with 18% strain (PPy/DBS had 8.5% strain), 2 times better strain rates, 1.8 times higher electronic conductivity, 1.4 times higher charge densities and 1.5 times higher diffusion coefficients in comparison to PPy/DBS. Long-term measurements up to 1000 cycles at 0.1 Hz revealed strain over 4% for PPy-PEO linear actuators, showing that combination of PPy/DBS with PEO gives excellent material for artificial muscle-like applications envisaged for smart textiles and soft robotics. FTIR and Raman spectroscopy confirmed PEO content in PPy. Electrochemical impedance spectroscopy (EIS) of PPy samples revealed 1.3 times higher ion conductivity of PPy-PEO films in PC solvent. Scanning electron microscopy (SEM) was used to investigate morphologies of PPy samples, and EDX spectroscopy was conducted to determine ion contents of oxidized/reduced films.
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Steel slag is an industrial by product of steel manufacturing processes and has been widely utilized within civil and construction materials for road materials and environmental remediation in countries like Japan, USA, and European Union nations. However, the current utilization of steel slag in Vietnam is very low mainly because of lack of quality control of slag treatment and chances for reuse of treated steel slag. This paper presents the up to date steel slag production status in Vietnam through the extensive survey and sampling at seven large steel factories. The paper also highlights the environmental and quality control issues of these steel slags to use as road construction aggregates by assessing the heavy metals concentration in the leachate. The basic oxygen furnace (BOF) and electric arc furnace (EAF) slag samples were collected to evaluate leaching properties of metals leached from the slags. The two standardized batch leaching tests of steel slag roadbed material in Japan (JIS K 0058-1) and toxicity characteristics leaching procedure (TCLP-EPA method 1311) were performed to the evaluated the hazardous metals. The results of the leaching test show that almost all of the concentration of the metals in the leached solution does not exceed the National Standard for Industrial Wastewater Discharge (QCVN 40-2011). The pH and parameters such as total chromium, nickel, copper, lead, arsenic, and manganese differ from the two test methods. The acidic conditions employed in the EPA 1311 were not representative of condition excepted during slag reuse in road constructions because in the operation condition of the road, acidic liquid is absent. The leaching test results confirmed that JIS test which uses deionized water with gentle mixing prevents the slag sample from size degradation is suitable for the environmental assessment of steel slag use for roadbed material. This research suggests that the adjustment of pH value prior to disposal or reuse as base materials and official guideline should be promulgate by the authorities to ensure the leachate meet the surface water quality standard.
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Metais Pesados , Aço , Povo Asiático , Humanos , Resíduos Industriais/análise , Controle de Qualidade , Aço/química , VietnãRESUMO
Polyoxyethylene tallow amine (POEA) is a nonionic surfactant added to insecticide and herbicide formulations. Experimental data have been shown the toxic effects of POEA on aquatic organisms and remain to be a serious concern. In this study, total of thirty-two potential bacteria that were isolated from herbicide-contaminated soil samples showed the ability to use POEA as the sole carbon and energy source. In which, a bacterial strain LA was further investigated based on the efficiency utilization of POEA and classified as Kosakonia oryzae by the 16S rRNA gene. Response surface methodology was successfully applied to understand the interaction of distinct factors on POEA degradation by LA strain. Degradation of POEA was confirmed with UV-Visible spectrophotometric analysis and HPLC analysis. The POEA utilization mechanism was explored by target gene detection and carbon source utilization. The results indicate that strain LA has the potential to serve as an in situ candidate for bioremediation polluted by POEA.
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Polietilenoglicóis , Poluentes do Solo , Aminas , Biodegradação Ambiental , Enterobacteriaceae , Gorduras , RNA Ribossômico 16S/genética , Solo , Microbiologia do SoloRESUMO
Following the natural muscle antagonist actuation principle, different adaptations for "artificial muscles" are introduced in this work. Polypyrrole (PPy) films of different polymerization techniques (potentiostatic and galvanostatic) were analyzed and their established responses were combined in several ways, resulting in beneficial actuation modes. A consecutive "one-pot" electrosynthesis of two layers with the different deposition regimes resulted in an all-PPy bending hybrid actuator. While in most cases the mixed-ion activity of conductive polymers has been considered a problem or a drawback, here for the first time, the nearly equal expansions upon oxidation and reduction of carefully selected conditions further allowed to fabricate a "mirrored" trilayer laminate, which behaved as a linear actuator.
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Modern personal protective armor has been generally based on the Kevlar fabrics, with the main goal to offer defense against bullets. In addition to the high cost and poor processability, Kevlar has the disadvantage of limited stab-proofing capability. On the other hand, a large number of crimes involving deadly injures represent knife attacks. Our goal in this work was to investigate composites based on traditional commercially available fabrics of linen and silk, using different adhesives-polymers for forming laminates. The silk composites also contained different amounts of in-woven polyester. Three different water-based adhesives of polyurethane, urea formaldehyde and polyvinyl alcohol were considered. It was found, that besides the strength of the fabrics themselves, the adhesives polymers played a crucial role in the obtained performance of the laminates. The laminates were characterized in their mechanical properties, as well as with scanning electron microscopy and FTIR spectroscopy.
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BACKGROUND: Insulinoma-associated protein 1 (INSM1), a transcriptional regulator with a zinc-finger DNA-binding domain, has been validated as a cytoplasmic marker for neuroendocrine differentiation of tumor cells. Next to its abundant expression in the fetal pancreas, it is expressed in brain tumors, pheochromocytomas, medullary thyroid carcinomas, insulinomas and pituitary and small-cell lung carcinomas. INSM1 is not expressed in normal adult tissues and/or most non-neuroendocrine tumors. It regulates various downstream signaling pathways, including the Sonic Hedgehog, PI3K/AKT, MEK/ERK1/2, ADK, p53, Wnt, histone acetylation, LSD1, cyclin D1, Ascl1 and N-Myc pathways. Although INSM1 appears to be a subtle and specific biomarker for neuroendocrine tumors, its role in tumor development has remained unclear. CONCLUSIONS: Here, we highlight INSMI expression, as well as its diagnostic significance and use as a therapeutic target in various neuroendocrine tumors. Targeting signaling pathways or gene expression alterations associated with INSM1 expression may be instrumental for the design of novel therapeutic strategies for neuroendocrine tumors.
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Biomarcadores Tumorais/metabolismo , Terapia de Alvo Molecular , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/metabolismo , Proteínas Repressoras/metabolismo , Diferenciação Celular , Humanos , Modelos Biológicos , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/patologia , Proteínas Repressoras/químicaRESUMO
Combining ink-jet printing and one of the most stable electroactive materials, PEDOT:PSS (poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)), is envisaged to pave the way for the mass production of soft electroactive materials. Despite its being a well-known electroactive material, widespread application of PEDOT:PSS also requires good understanding of its response. However, agreement on the interpretation of the material's activities, notably regarding actuation, is not unanimous. Our goal in this work is to study the behavior of trilayers with PEDOT:PSS electrodes printed on either side of a semi-interpenetrated polymer network membrane in propylene carbonate solutions of three different electrolytes, and to compare their electroactive, actuation, and energy storage behavior. The balance of apparent faradaic and non-faradaic processes in each case is discussed. The results show that the primarily cation-dominated response of the trilayers in the three electrolytes is actually remarkably different, with some rather uncommon outcomes. The different balance of the apparent charging mechanisms makes it possible to clearly select one electrolyte for potential actuation and another for energy storage application scenarios.
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Rhodosporidium toruloides strain VN1 is of special interest because of its capability for high astaxanthin production. Here, we report the draft genome sequence of R. toruloides VN1, which comprises 20.01 Mb in 424 contigs with an overall G + C content of 61.8%. This whole-genome shotgun project has been deposited at DDBJ/EMBL/GenBank under the accession number SJTE00000000.
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Bacteria in the environment play a major role in the degradation of widely used man-made recalcitrant organic compounds. Pseudomonas nitroreducens TX1 is of special interest because of its high efficiency to remove nonionic ethoxylated surfactants. In this study, a novel approach was demonstrated by a bacterial enzyme involved in the formation of radicals to attack ethoxylated surfactants. The dihydrolipoamide dehydrogenase was purified from the crude extract of strain TX1 by using octylphenol polyethoxylate (OPEOn) as substrate. The extent of removal of OPEOs during the degradation process was conducted by purified recombinant enzyme from E. coli BL21 (DE3) in the presence of the excess of metal mixtures (Mn2+, Mg2+, Zn2+, and Cu2+). The metabolites and the degradation rates were analyzed and determined by liquid chromatography-mass spectrometry. The enzyme was demonstrated to form Fenton reagent in the presence of an excess of metals. Under this in vitro condition, it was shown to be able to shorten the ethoxylate chains of OPEOn. After 2 hours of reaction, the products obtained from the degradation experiment revealed a prominent ion peak at m/z = 493.3, namely the ethoxylate chain unit is 6 (OPEO6) compared to OPEO9 (m/z = 625.3), the main undegraded surfactant in the no enzyme control. It revealed that the concentration of OPEO15 and OPEO9 decreased by 90% and 40% after 4 hours, respectively. The disappearance rates for the OPEOn homologs correlated to the length of the exothylate chains, suggesting it is not a specific enzymatic reaction which cleaves one unit by unit from the end of the ethoxylate chain. The results indicate the diverse and novel strategy by bacteria to catabolize organic compounds by using existing housekeeping enzyme(s).
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Proteínas de Bactérias/metabolismo , Di-Hidrolipoamida Desidrogenase/metabolismo , Fenóis/química , Fenóis/metabolismo , Pseudomonas/enzimologia , Tensoativos/química , Tensoativos/metabolismo , Cromatografia Líquida , Cobre/metabolismo , Escherichia coli/enzimologia , Magnésio/metabolismo , Manganês/metabolismo , Espectrometria de Massas , Zinco/metabolismoRESUMO
Emulsifiers like polysorbate family, carboxymethyl cellulose are widely used in the preparation of drugs, vaccines, food, cosmetics, and skin care products. In this study, strain SP2 is isolated for the high-efficiency utilization of emulsifier as its sole carbon and energy source. Strain grows on the polysorbate family with generation time ranging from 0.8 to 2.2 h. It is sensitive to ampicillin, gentamicin, imipenem, penicillin, and vancomycin, but resistant to amikacin, cefoxitin, erythromycin, kanamycin, nalidixic acid, and tetracycline. Based on 16S rRNA gene, strain is identified as Acinetobacter soli. Compared to M. pamicella, which is capable of degrading 50% polysorbate 80 within 3 days, isolate PS2 could dispose 51.6% polysorbate 80 within only 8 h. Using cell crude extract from strain SP2, the liberation of free fatty acid in the reaction mixture containing polysorbate 80 suggests that the mechanism for polysorbate utilization belongs to the ß-oxidation.
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Acinetobacter/metabolismo , Emulsificantes/metabolismo , Aditivos Alimentares/metabolismo , Polissorbatos/metabolismo , Acinetobacter/efeitos dos fármacos , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Ampicilina/farmacologia , Antibacterianos/farmacologia , Farmacorresistência BacterianaRESUMO
Two new alkaloids, desmorostratine (1) and discretine N-oxide (2), were isolated from the stem bark of Desmos rostrata, together with five known alkaloids, discretine (3), dehydrodiscretine (4), pseudocolumbamine (5), predicentrine (6), and aristolactam AII (7). The structures were established on the basis of spectroscopic data, including mass spectrometry and 2D-NMR. Compound 1 was cytotoxic against KB cells (IC(50) 2.4 microM), while 2, 3, and 4 inhibited Plasmodium falciparum (IC(50) of 4.2, 1.6, and 0.9 microM, respectively).
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Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Plantas Medicinais/química , Plasmodium falciparum/efeitos dos fármacos , Alcaloides/química , Animais , Antimaláricos/química , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Heterocíclicos de 4 ou mais Anéis/química , Humanos , Células KB , Estrutura Molecular , Casca de Planta/química , VietnãRESUMO
Prospective study , include 49 patients with 54 sessions were treated by the ligation method combined with endoscopic sclerotherapy in the bleeding due to esophageal variceal rupture since 3/1999-3/2002, in Binh Dan hospital. Results: 92.6% patients were moderate and severe bleeding; 100% patients have varices grade II and grade III; 89% seeing signs of severe bleeding at endoscopy; the hemostate effect in initial 48 hours is 100% with the average quantity of elastic band: 2.7 ± 0.8 and the average volume of sclerosant: 34 ± 8ml polidocanol 1%. This is a therapeutic method that have good hemostasis efficacy and safety method to patients in emergency