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1.
BMC Anesthesiol ; 23(1): 348, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37864142

RESUMO

BACKGROUND: A simulated education, prior to surgery about postoperative nasal stuffiness and ease of breathing through the mouth may help patients tolerate discomfort after nasal surgery. This study aimed to investigate the effect of preoperative simulated education on immediate postoperative opioid requirements in patients undergoing elective nasal surgery. METHODS: This randomized controlled trial of 110 patients undergoing nasal surgery randomly allocated patients into either a control (group C) or an education group (group E). One day before surgery, patients in group E were intensively trained to breathe through the mouth by using a nasal clip, with informative explanations about inevitable nasal obstruction and discomfort following surgery. Patients in group C were provided with routine preoperative information. Total intravenous anesthesia (TIVA) with propofol and remifentanil was used for anesthesia. No further opioid was used for analgesia intraoperatively. The primary outcome was index opioid (fentanyl) requirements at the post-anesthesia recovery unit (PACU). Secondary outcomes were emergence agitation, pain scores at the PACU, and postoperative recovery using the Quality of Recovery-15 (QoR15-K). RESULTS: The rate of opioid use in the PACU was 51.0% in the group E and 39.6% in the group C (p = 0.242). Additional request for analgesics other than index opioid was not different between the groups. Emergence agitation, postoperative pain severity, and QoR15-K scores were comparable between the groups. CONCLUSION: Preoperative education with simulated mouth breathing in patients undergoing nasal surgery did not reduce opioid requirements. TRIAL REGISTRATION: KCT0006264; 16/09/2021; Clinical Research Information Services ( https://cris.nih.go.kr ).


Assuntos
Delírio do Despertar , Procedimentos Cirúrgicos Nasais , Humanos , Analgésicos Opioides/uso terapêutico , Delírio do Despertar/tratamento farmacológico , Respiração Bucal/tratamento farmacológico , Educação de Pacientes como Assunto , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Anestesia Geral
2.
Environ Sci Technol ; 50(4): 1788-95, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26771993

RESUMO

Quorum quenching (QQ) has recently been acknowledged to be a sustainable antifouling strategy and has been investigated widely using lab-scale membrane bioreactor (MBR) systems. This study attempted to bring this QQ-MBR closer to potential practical application. Two types of pilot-scale QQ-MBRs with QQ bacteria entrapping beads (QQ-beads) were installed and run at a wastewater treatment plant, feeding real municipal wastewater to test the systems' effectiveness for membrane fouling control and thus the amount of energy savings, even under harsh environmental conditions. The rate of transmembrane pressure (TMP) build-up was significantly mitigated in QQ-MBR compared to that in a conventional-MBR. Consequently, QQ-MBR can substantially reduce energy consumption by reducing coarse bubble aeration without compromising the effluent water quality. The addition of QQ-beads to a conventional MBR substantially affected the EPS concentrations, as well as microbial floc size in the mixed liquor. Furthermore, the QQ activity and mechanical stability of QQ-beads were well maintained for at least four months, indicating QQ-MBR has good potential for practical applications.


Assuntos
Fenômenos Fisiológicos Bacterianos , Reatores Biológicos/microbiologia , Percepção de Quorum , Eliminação de Resíduos Líquidos/instrumentação , Aerobiose , Proteínas de Bactérias/metabolismo , Incrustação Biológica , Floculação , Laboratórios , Membranas , Membranas Artificiais , Projetos Piloto , Polissacarídeos Bacterianos/metabolismo , Pressão , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias
3.
Environ Sci Technol ; 50(20): 10914-10922, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27634354

RESUMO

In the last 30 years, the use of membrane bioreactors (MBRs) for advanced wastewater treatment and reuse have been expanded continuously, but they still suffer from excessive energy consumption resulting from the intrinsic problem of membrane biofouling. One of the major causes of biofouling in MBRs is bacterial quorum sensing (QS) via N-acylhomoserine lactones (AHLs) and/or autoinducer-2 (AI-2), enabling intra- and interspecies communications, respectively. In this study, we demonstrate that farnesol can substantially mitigate membrane biofouling in a MBR due to its quorum quenching (QQ) activity. When Candida albicans (a farnesol producing fungus) entrapping polymer beads (AEBs) were placed in the MBR, the rate of transmembrane pressure (TMP) rise-up was substantially decreased, even for lower aeration intensities. This finding corresponds to a specific aeration energy savings of approximately 40% (25% through the physical washing effect and a further 15% through the biological QQ effect of AEBs) compared to conventional MBRs without AEBs. A real-time RT-qPCR analysis revealed that farnesol secreted from C. albicans mitigated the biofilm formation in MBRs via the suppression of AI-2 QS. Successful control of biofouling and energy savings through fungal-to-bacterial QQ could be expanded to the plant scale for MBRs in wastewater treatment with economic feasibility.


Assuntos
Percepção de Quorum/efeitos dos fármacos , Águas Residuárias , Incrustação Biológica , Reatores Biológicos/microbiologia , Membranas Artificiais , Eliminação de Resíduos Líquidos
4.
Am J Orthod Dentofacial Orthop ; 145(4): 486-95, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24703287

RESUMO

INTRODUCTION: The purpose of this study was to investigate the influence of the timing of orthodontic force application on the rates of orthodontic tooth movement into surgical alveolar defects with bone grafts in beagle dogs. METHODS: Twelve beagles were randomly divided into 2 groups according to the surgical procedure: alveolar osteotomy alone (control) or osteotomy with bone graft (experimental group). The maxillary second premolars were protracted for 6 weeks into the surgical sites: immediately, at 2 weeks, and at 12 weeks after surgery. The orthodontic tooth movement rates and alveolar remodeling concomitant with surgical defect healing were evaluated by model measurements and histomorphometry as well as microcomputed tomography and histology. One-way analysis of variance and the Scheffé post hoc comparison were performed for investigating the rates of orthodontic tooth movement and mineralized bone formation. RESULTS: Both the orthodontic tooth movement rate and the mean appositional length of mineralized bone in the tension side of teeth were significantly accelerated when force was applied at 2 weeks in the control group and immediately in the experimental group (P <0.001). The 2-week control group showed a dramatic increase in apposition rate during 4 to 6 weeks after force application, whereas the immediate protraction experimental group did within the first 3 weeks (P <0.001). Decreased orthodontic tooth movement rates and reduced bone remodeling activities were apparent in the 12-weeks groups, especially in nongrafted defects. CONCLUSIONS: A bone graft into the surgical defect can not only allow immediate force application for accelerating orthodontic tooth movement with favorable periodontal regeneration, but also decrease the risk of inhibited orthodontic tooth movement in case of delayed force application after surgery.


Assuntos
Transplante Ósseo/métodos , Doenças Maxilares/cirurgia , Técnicas de Movimentação Dentária/métodos , Processo Alveolar/patologia , Processo Alveolar/cirurgia , Animais , Dente Pré-Molar/cirurgia , Densidade Óssea/fisiologia , Matriz Óssea/transplante , Remodelação Óssea/fisiologia , Substitutos Ósseos/uso terapêutico , Calcificação Fisiológica/fisiologia , Cães , Masculino , Doenças Maxilares/patologia , Minerais/uso terapêutico , Fechamento de Espaço Ortodôntico/instrumentação , Fechamento de Espaço Ortodôntico/métodos , Osteogênese/fisiologia , Osteotomia/métodos , Distribuição Aleatória , Estresse Mecânico , Fatores de Tempo , Extração Dentária , Técnicas de Movimentação Dentária/instrumentação , Alvéolo Dental/cirurgia , Microtomografia por Raio-X
5.
Sci Rep ; 12(1): 16765, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36202918

RESUMO

Congenital hyperinsulinism (CHI) is a rare genetic condition characterized by uncontrolled insulin secretion, resulting in hypoglycemia. Although glucagon has lately been regarded as a therapeutic option for CHI, its use is severely hampered by its poor solubility and stability at physiological pH, as well as its short duration of action. To address these constraints, we developed HM15136, a novel long-acting glucagon analog composed of a glucagon analog conjugated to the Fc fragment of human immunoglobulin G4 via a polyethylene glycol linker. In this study, we established that HM15136 was more soluble than natural glucagon (≥ 150 mg/mL vs 0.03 mg/mL). Next, we confirmed that HM15136 activated glucagon receptor in vitro and induced glycogenolysis and gluconeogenesis in rat primary hepatocytes. Pharmacokinetics (PK)/Pharmacodynamics (PD) analysis of HM15136 shows that HM15136 has a markedly longer half-life (36 h vs. < 5 min) and increased bioavailability (90%) compared to native glucagon in mice. Further, HM15136 could effectively reverse acute hypoglycemia induced by insulin challenge, and multiple doses of HM15136 could sustain increased blood glucose levels in CHI rats. In conclusion, our findings indicate that HM15136 promotes sustained elevation of blood glucose, demonstrating the potential for development as a once-weekly therapy for CHI.


Assuntos
Hiperinsulinismo Congênito , Hiperinsulinismo , Animais , Humanos , Camundongos , Ratos , Glicemia/análise , Hiperinsulinismo Congênito/tratamento farmacológico , Glucagon , Meia-Vida , Hiperinsulinismo/tratamento farmacológico , Fragmentos Fc das Imunoglobulinas , Insulina/farmacologia , Polietilenoglicóis/farmacologia , Receptores de Glucagon , Roedores
6.
J Clin Med ; 10(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34074066

RESUMO

Patients with chronic renal failure (CRF) are likely to have obstructive sleep apnea (OSA) underdiagnosed, and maintaining airway patency is important during sedation. This study compared Jaw elevation device (JED) with conventional airway interventions (head lateral rotation, neck extension, oral or nasal airway insertion, and jaw thrust maneuver) during sedation and hypothesized that JED may be effective to open the airway. A total of 73 patients were allocated to a conventional group (n = 39) and a JED group (n = 34). The number of additional airway interventions was the primary outcome. Percentage of patients with no need of additional interventions and apnea-hypopnea index (AHI) were secondary outcomes. The number of additional interventions was significantly less in the JED group compared to the conventional group (0 (0-0) vs. 1 (0-2); p = 0.002). The percentage of patients with no requirement for additional interventions was significantly higher in the JED group compared to the conventional group (76.5% vs. 43.6%; p = 0.004). AHI was significantly lower in the JED group compared to the conventional group (4.5 (1.5-11.9) vs. 9.3 (3.8-21.9), p = 0.015). In conclusion, JED seems to be effective in opening the airway patency during sedation in CRF patients.

7.
Biotechnol Bioeng ; 105(1): 150-60, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19937726

RESUMO

For the synthesis of polylactic acid (PLA) and its copolymers by one-step fermentation process, heterologous pathways involving Clostridium propionicum propionate CoA transferase (Pct(Cp)) and Pseudomonas sp. MBEL 6-19 polyhydroxyalkanoate (PHA) synthase 1 (PhaC1(Ps6-19)) were introduced into Escherichia coli for the generation of lactyl-CoA endogenously and incorporation of lactyl-CoA into the polymer, respectively. Since the wild-type PhaC1(Ps6-19) did not efficiently accept lactyl-CoA as a substrate, site directed mutagenesis as well as saturation mutagenesis were performed to improve the enzyme. The wild-type Pct(Cp) was not able to efficiently convert lactate to lactyl-CoA and was found to exert inhibitory effect on cell growth, random mutagenesis by error-prone PCR was carried out. By employing engineered PhaC1(Ps6-19) and Pct(Cp), poly(3-hydroxybutyrate-co-lactate), P(3HB-co-LA), containing 20-49 mol% lactate could be produced up to 62 wt% from glucose and 3HB. By controlling the 3HB concentration in the medium, PLA homopolymer and P(3HB-co-LA) containing lactate as a major monomer unit could be synthesized. Also, P(3HB-co-LA) copolymers containing various lactate fractions could be produced from glucose alone by introducing the Cupriavidus necator beta-ketothiolase and acetoacetyl-CoA reductase genes. Fed-batch cultures were performed to produce P(3HB-co-LA) copolymers having 9-64 mol% of lactate, and their molecular weights, thermal properties, and melt flow properties were determined.


Assuntos
Aciltransferases/metabolismo , Clostridium/enzimologia , Coenzima A-Transferases/metabolismo , Ácido Láctico/biossíntese , Aciltransferases/química , Western Blotting , Escherichia coli/genética , Estrutura Molecular , Mutação , Poliésteres , Polímeros , Proteínas Recombinantes/genética , Transdução de Sinais
8.
Int J Biol Macromol ; 165(Pt A): 187-197, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32991892

RESUMO

In this work, twenty-five kinds of choline chloride (ChCl)-based deep eutectic solvents (DESs) containing acid, hydroxyl, amide, and binary hydrogen bond donors (HBDs) were prepared and successfully used to pretreat pine wood powder. As a result of the pretreatment, the glucan content in the pretreated biomass was increased, whereas the contents of hemicellulose and lignin were significantly decreased. The biomass pretreatment efficiency of the DESs had improved with increasing the polarity and hydrogen bond acidity (α) of the DESs. Among the studied DESs, ChCl:lactic acid:formic acid (1:1:1) with the highest α value was the most efficient DES in extracting lignin from biomass. The pretreated biomass also showed an enhanced enzymatic saccharification yield owing to the decreased particle size of the biomass and reduced content of hemicellulose and lignin. During the pretreatment process of biomass using DESs, the extracted lignin could be recovered successfully, with a yield of up to 60% and purity of over 90%. The molecular weight of the extracted lignin was much lower than that of the native cellulolytic enzyme lignin. The DES used for pretreatment process could be also successfully reused with high recovery yield of DES and high retention of delignification capacity.


Assuntos
Colina/química , Lignina/isolamento & purificação , Pinus/química , Madeira/química , Biomassa , Celulose/química , Ligação de Hidrogênio , Hidrólise , Lignina/química , Polissacarídeos/química , Solventes/química
9.
Biotechnol Bioeng ; 102(5): 1368-76, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19090482

RESUMO

Lignocellulose represents a key sustainable source of biomass for transformation into biofuels and bio-based products. Unfortunately, lignocellulosic biomass is highly recalcitrant to biotransformation, both microbial and enzymatic, which limits its use and prevents economically viable conversion into value-added products. As a result, effective pretreatment strategies are necessary, which invariably involves high energy processing or results in the degradation of key components of lignocellulose. In this work, the ionic liquid, 1-ethyl-3-methylimidazolium acetate ([Emim][CH3COO]), was used as a pretreatment solvent to extract lignin from wood flour. The cellulose in the pretreated wood flour becomes far less crystalline without undergoing solubilization. When 40% of the lignin was removed, the cellulose crystallinity index dropped below 45, resulting in > 90% of the cellulose in wood flour to be hydrolyzed by Trichoderma viride cellulase. [Emim] [CH3COO] was easily reused, thereby resulting in a highly concentrated solution of chemically unmodified lignin, which may serve as a valuable source of a polyaromatic material as a value-added product.


Assuntos
Biotecnologia/métodos , Celulose/metabolismo , Indústrias Extrativas e de Processamento/métodos , Lignina/isolamento & purificação , Trichoderma/metabolismo , Madeira/química , Hidrólise , Imidazóis/química , Solventes/química
10.
Adv Biochem Eng Biotechnol ; 168: 133-176, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30242432

RESUMO

Biopolymer-based composite materials have many potential applications in biomedical, pharmaceutical, environmental, biocatalytic, and bioelectronic fields, owing to their inherent biocompatibility and biodegradability. When used as solvents, ionic liquids can be used to fabricate biopolymers such as polysaccharides and proteins into various forms, including molded shapes, films, fibers, and beads. This article summarizes the processes for preparing biopolymer-based composite materials using ionic liquids. The processes include biopolymer dissolution using ionic liquids, regeneration of the biopolymer by an anti-solvent, formation of shapes, and drying of the regenerated biopolymer. In particular, the preparation and applications of biopolymer blend-based composite materials containing two or more biopolymers are addressed.


Assuntos
Biopolímeros , Líquidos Iônicos , Biopolímeros/química , Líquidos Iônicos/química , Solventes/química
11.
J Orthop Surg (Hong Kong) ; 27(1): 2309499019831480, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30827170

RESUMO

PURPOSE: Fingertip replantation is a challenging and technically demanding procedure. A variety of venous drainage techniques have been attempted for successful fingertip replantation. We present a new venous drainage technique, known as serial multifocal incision for fingertip replantation. METHODS: Between 2006 and 2014, we performed 94 fingertip replantations without vein anastomosis. Eighty of the patients were male, and 14 were female, with an overall mean age of 42 years (range: 8-67 years). All patients suffered amputations distal to the distal phalanx joint (Ishikawa subzone I, II, or III). We performed only artery anastomosis. To relieve venous congestion, we incised the fingertip 2-3 mm using a number 11 scalpel blade and allowed the vein to drain naturally. We made small serial incisions every 2-3 days for 1 week. RESULTS: The overall success rate for this procedure was 90%, with 85 surviving digits. Two patients with partial necrosis and nine patients with complete loss needed a second operation. Two patients received blood transfusions with an average of 1.5 units, but both had an accompanying injury at another site. No one complained of nail deformity or wound infection. CONCLUSIONS: Various external bleeding techniques have been reported to yield good results. The serial stab incision venous drainage technique is a modified fish-mouth external bleeding technique that overcomes the disadvantages of published methods. This technique is simple, allows for easy control of venous drainage, and reduces the need for blood transfusions compared to other venous drainage techniques that cause large amounts of bleeding. We propose a new method, the serial stab incision venous drainage technique, which is effective and associated with high rates of survival.


Assuntos
Amputação Traumática/cirurgia , Drenagem , Traumatismos dos Dedos/cirurgia , Reimplante/métodos , Procedimentos Cirúrgicos Vasculares , Adolescente , Adulto , Idoso , Anastomose Cirúrgica , Artérias , Transfusão de Sangue , Criança , Feminino , Dedos/irrigação sanguínea , Dedos/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ferida Cirúrgica , Adulto Jovem
12.
Chem Commun (Camb) ; (40): 5022-4, 2008 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-18931773

RESUMO

We report novel heparin-cellulose-charcoal composites prepared using room temperature ionic liquids (RTILs) to enhance the biocompatibility and blood compatibility of activated charcoal beads while decreasing the size of their active pores.


Assuntos
Celulose/química , Carvão Vegetal/química , Heparina/química , Líquidos Iônicos/química , Desintoxicação por Sorção/métodos , Adsorção , Animais , Materiais Biocompatíveis/química , Bovinos , Proteínas/química , Temperatura
13.
J Nanosci Nanotechnol ; 8(9): 4734-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19049097

RESUMO

General synthetic methods for silver nanoparticles are reduction of metal salt in aqueous solution or alcoholic solution. However, the preparation of silver nanoparticles in organic solvent is rarely reported. The most common preparation methods for silver nanoparticles in organic solvent are based on transfer of nanoparticles from aqueous phase to organic phase by phase transfer agent. We describe an easy synthetic method to prepare dispersed silver nanoparticles (approximately 10 nm) by reduction of silver cation in organic solvent such as toluene using a reducing agent and a capping agent. The synthesized silver nanoparticles and polycarbonate were mixed and molded to prepare a new composite in methylene chloride. The composite was tested to investigate antifungal effect by coliform (Escherichia coil ATCC 25922). The antifungal effect of the composite reached high after 24 h (99.9999%). The composite and the silver nanoparticles have been characterized using X-ray diffraction (XRD), UV-vis spectroscopy, transmission electron microscopy (TEM), and inductively coupled plasma (ICP).


Assuntos
Antifúngicos/síntese química , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Cimento de Policarboxilato/química , Prata/química , Antifúngicos/farmacologia , Cristalização , Enterobacteriaceae/metabolismo , Escherichia coli/metabolismo , Cloreto de Metileno/química , Microscopia Eletrônica de Transmissão/métodos , Nanocompostos/química , Nanoestruturas/química , Espectrofotometria Ultravioleta/métodos , Propriedades de Superfície
14.
J Microbiol Biotechnol ; 27(3): 552-560, 2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-27974728

RESUMO

Quorum quenching (QQ) bacteria entrapped in a polymeric composite hydrogel (QQ medium) have been successfully applied in membrane bioreactors (MBRs) for effective biofouling control. However, in order to bring QQ technology closer to practice, the physical strength and lifetime of QQ media should be improved. In this study, enforcement of physical strength, as well as an extension of the lifetime of a previously reported QQ bacteria entrapping hollow cylinder (QQ-HC), was sought by adding a dehydration procedure following the cross-linking of the polymeric hydrogel by inorganic compounds like Ca2+ and boric acid. Such prepared medium demonstrated enhanced physical strength possibly through an increased degree of physical cross-linking. As a result, a longer lifetime of QQ-HCs was confirmed, which led to improved biofouling mitigation performance of QQ-HC in an MBR. Furthermore, QQ-HCs stored under dehydrated condition showed higher QQ activity when the storage time lasted more than 90 days owing to enhanced cell viability. In addition, the dormant QQ activity after the dehydration step could be easily restored through reactivation with real wastewater, and the reduced weight of the dehydrated media is expected to make handling and transportation of QQ media highly convenient and economical in practice.


Assuntos
Fenômenos Fisiológicos Bacterianos , Desidratação , Íons/metabolismo , Reatores Biológicos , Meios de Cultura , Fermentação , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Viabilidade Microbiana
15.
Carbohydr Polym ; 157: 137-145, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-27987845

RESUMO

Alginate/bacterial cellulose nanocomposite beads, with well-controlled size and regular spherical shapes, were prepared in a simple manner by entrapping Gluconacetobacter xylinus in barium alginate hydrogel beads, followed by cultivation of the entrapped cells in culture media with a low sodium ion concentration. The entire surface of the alginate hydrogel beads containing the cells was covered with cellulose fibers (∼30nm) after 36h of cultivation. The cellulose crystallinity index of the alginate/bacterial cellulose beads was 0.7, which was slightly lower than that of bacterial cellulose prepared by cultivating dispersed cells. The water vapor sorption capacity of the alginate/bacterial cellulose beads increased significantly from 0.07 to 38.00 (g/g dry bead) as cultivation time increased. These results clearly indicate that alginate/bacterial cellulose beads have a much higher surface area, crystallinity, and water-holding capacity than alginate beads. The immobilization of lipase on the surface of the nanocomposite beads was also investigated as a potential application of this system. The activity and specific activity of lipase immobilized on alginate/bacterial cellulose beads were 2.6- and 3.8-fold higher, respectively, than that of lipase immobilized on cellulose beads. The alginate/bacterial cellulose nanocomposite beads prepared in this study have several potential applications in the biocatalytic, biomedical, and pharmaceutical fields because of their biocompatibility, biodegradability, high crystallinity, and large surface area.


Assuntos
Alginatos/química , Celulose/química , Gluconacetobacter xylinus/química , Lipase/química , Enzimas Imobilizadas/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Nanocompostos
16.
J Microbiol Biotechnol ; 27(3): 573-583, 2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28068666

RESUMO

Biofilm formation on the membrane surface results in the loss of permeability in membrane bioreactors (MBRs) for wastewater treatment. Studies have revealed that cellulose is not only produced by a number of bacterial species but also plays a key role during formation of their biofilm. Hence, in this study, cellulase was introduced to a MBR as a cellulose-induced biofilm control strategy. For practical application of cellulase to MBR, a cellulolytic (i.e., cellulase-producing) bacterium, Undibacterium sp. DM-1, was isolated from a lab-scale MBR for wastewater treatment. Prior to its application to MBR, it was confirmed that the cell-free supernatant of DM-1 was capable of inhibiting biofilm formation and of detaching the mature biofilm of activated sludge and cellulose-producing bacteria. This suggested that cellulase could be an effective anti-biofouling agent for MBRs used in wastewater treatment. Undibacterium sp. DM-1-entrapping beads (i.e., cellulolytic-beads) were applied to a continuous MBR to mitigate membrane biofouling 2.2-fold, compared with an MBR with vacant-beads as a control. Subsequent analysis of the cellulose content in the biofilm formed on the membrane surface revealed that this mitigation was associated with an approximately 30% reduction in cellulose by cellulolytic-beads in MBR.


Assuntos
Incrustação Biológica , Reatores Biológicos , Celulose/metabolismo , Fermentação , Oxalobacteraceae/fisiologia , Esgotos/microbiologia , Biofilmes , Celulase/metabolismo , Oxalobacteraceae/isolamento & purificação
17.
Angle Orthod ; 86(2): 206-13, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26154938

RESUMO

OBJECTIVE: To investigate combined effect of photobiomodulation with a matrix metalloproteinase (MMP) inhibitor on the relapse rate in relation to MMP expression in rats. MATERIALS AND METHODS: Fifty-two rats were divided into four groups according to the treatment modality: control group, irradiation group, doxycycline group, and irradiation with doxycycline group. During a relapse period of 5 days after orthodontic movement, maxillary central incisors were treated by low-level laser therapy (LLLT) as a photobiomodulation and/or doxycycline as a synthetic MMP inhibitor. Relapse rate was evaluated in association with MMP expression at the gene and protein levels. RESULTS: Relapse rates were increased by LLLT (1.57-fold) and decreased by doxycycline (0.83-fold) compared with the control, showing positive correlation with the levels of expression for all MMPs in the periodontal ligament (PDL). LLLT concomitant with doxycycline administration resulted in no significant differences of relapse rate and MMP expression from the control. CONCLUSIONS: The combined effect of photobiomodulation with an MMP inhibitor around the relapsing teeth proved to be antagonistic to PDL remodeling activity during relapse. This study suggests a basis for developing a novel biologic procedure targeting the MMP-dependent PDL remodeling to control the relapse rate.


Assuntos
Terapia com Luz de Baixa Intensidade , Inibidores de Metaloproteinases de Matriz/farmacologia , Ligamento Periodontal/metabolismo , Técnicas de Movimentação Dentária , Animais , Doxiciclina/farmacologia , Ligamento Periodontal/efeitos da radiação , Ratos , Recidiva
18.
J Microbiol Biotechnol ; 26(10): 1746-1754, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27381336

RESUMO

Recently, spherical beads entrapping quorum quenching (QQ) bacteria have been reported as effective moving QQ-media for biofouling control in MBRs for wastewater treatment owing to their combined effects of biological (i.e., quorum quenching) and physical washing. Taking into account both the mass transfer of signal molecules through the QQ-medium and collision efficiencies of the QQ-medium against the filtration membranes in a bioreactor, a cylindrical medium (QQ-cylinder) was developed as a new shape of moving QQ-medium. The QQ-cylinders were compared with previous QQ-beads in terms of the QQ activity and the physical washing effect under identical loading volumes of each medium in batch tests. It was found that the QQ activity of a QQ-medium was highly dependent on its specific surface area, regardless of the shape of the medium. In contrast, the physical washing effect of a QQ-medium was greatly affected by its geometric structure. The enhanced anti-biofouling property of the QQ-cylinders relative to QQ-beads was confirmed in a continuous laboratory-scale MBR with a flat-sheet membrane module.


Assuntos
Incrustação Biológica/prevenção & controle , Reatores Biológicos , Membranas Artificiais , Percepção de Quorum , Águas Residuárias/microbiologia , Purificação da Água/métodos
19.
Carbohydr Polym ; 115: 223-9, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25439889

RESUMO

Wood component-based composite hydrogels have potential applications in biomedical fields owing to their low cost, biodegradability, and biocompatibility. The controllable properties of wood mimetic composites containing three major wood components are useful for enzyme immobilization. Here, lipase from Candida rugosa was entrapped in wood mimetic beads containing cellulose, xylan, and lignin by dissolving wood components with lipase in [Emim][Ac], followed by reconstitution. Lipase entrapped in cellulose/xylan/lignin beads in a 5:3:2 ratio showed the highest activity; this ratio is very similar to that in natural wood. The lipase entrapped in various wood mimetic beads showed increased thermal and pH stability. The half-life times of lipase entrapped in cellulose/alkali lignin hydrogel were 31- and 82-times higher than those of free lipase during incubation under denaturing conditions of high temperature and low pH, respectively. Owing to their biocompatibility, biodegradability, and controllable properties, wood mimetic hydrogel beads can be used to immobilize various enzymes for applications in the biomedical, bioelectronic, and biocatalytic fields.


Assuntos
Materiais Biomiméticos/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Hidrogéis/química , Microesferas , Madeira/química , Candida/enzimologia , Celulose/química , Estabilidade Enzimática , Lignina/química , Lipase/química , Lipase/metabolismo , Xilanos/química
20.
J Chromatogr A ; 988(2): 177-84, 2003 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-12641155

RESUMO

A headspace analysis for groundwater contaminated with BTEX (benzene, toluene, ethylbenzene, and xylenes) was employed to investigate the feasibility and limitations of Carboxen-PDMS (polydimethylsiloxane) fiber during SPME (solid-phase microextraction). Although the response of the Carboxen-PDMS fiber was much higher than that of conventional PDMS fiber, a reduction of the extracted amount was also observed under multi-component conditions due to competitive replacement. The general affinity of analytes to the fiber was high in the order xylene>ethylbenzene>toluene> benzene. The behavior of the Carboxen-PDMS fiber was examined more precisely at constant compositional ratio, because the analysis of contaminants using Carboxen-PDMS fiber was reported to be possible at known composition. The relative affinity of each component was shown to differ according to the total amount of analytes. Furthermore, the extracted amounts of benzene and toluene did not show a consistent tendency as the concentration of each component increased. These results indicate that caution should be exercised if Carboxen-PDMS fibers are used for the analysis of BTEX in groundwater samples.


Assuntos
Cromatografia Gasosa/métodos , Dimetilpolisiloxanos/química , Silicones/química , Poluentes Químicos da Água/análise
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