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1.
Arch Microbiol ; 204(1): 5, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34870749

RESUMO

Vibrio cholerae and Vibrio vulnificus are critical foodborne pathogens that need to be intensively controlled for their infection due to the intake and distribution of seafood, especially raw oysters. For this reason, various methods have already been developed for the detection and enumeration of these bacteria. The most probable number (MPN)-PCR (polymerase chain reaction) method is commonly used with the selective-differential medium for the efficiency and convenience of cell enumeration. One of the most frequently used for detecting Vibrio spp. is thiosulfate-citrate-bile salts-sucrose (TCBS) agar. But this selective-differential medium can fail to distinguish between V. cholerae, V. vulnificus, and Vibrio alginolyticus. For this reason, the conventional MPN-PCR method with TCBS medium for the detection of Vibrio spp. has a problem with processing PCR two times. This study suggests a simple and minimized detection method using one-time PCR and non-NaCl Luria-Bertani (LB-0) medium culture. This detection method is based on the difference in salt requirement between V. cholerae and V. vulnificus. Employing the developed methodology, the simultaneous cell enumeration of V. cholerae and V. vulnificus can be possible at a low cost. Furthermore, this study proposes a new specific primer to detect virulence-related genes from V. cholerae and V. vulnificus. This advanced MPN-PCR method was verified using bioaccumulated pacific oysters (Crassostrea gigas) by V. cholerae and V. vulnificus.


Assuntos
Ostreidae , Vibrio cholerae , Vibrio parahaemolyticus , Vibrio vulnificus , Animais , Reação em Cadeia da Polimerase , Vibrio cholerae/genética , Vibrio parahaemolyticus/genética , Vibrio vulnificus/genética
2.
Inorg Chem ; 60(16): 11825-11829, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34060321

RESUMO

Metal-organic frameworks (MOFs) undergo structural decomposition or phase transformation upon hydration in aqueous media or under harsh conditions, limiting their industrial commercialization. Herein, we present mechanochemical strategies to reconstruct four selected MOFs (MOF-5, MOF-177, UiO-67, and ZIF-65). To verify the effectiveness of this approach, these MOFs were intentionally decomposed in aqueous media and subsequently treated by ball milling under optimized conditions. As confirmed by X-ray diffraction analysis and N2 sorption isotherms, regardless of the MOF degradation pathway, the original structure could be recovered by a tailored mechanochemical reaction. This approach expands the practical applications of MOFs by enabling the regeneration of deteriorated MOFs quickly at a large scale.

3.
Appl Microbiol Biotechnol ; 104(2): 799-816, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31820066

RESUMO

Pseudomonas aeruginosa is known as an opportunistic pathogen whose one of the antibiotic resistance mechanisms includes biofilm formation and virulence factor production. The present study showed that the sub-minimum inhibitory concentration (sub-MIC) of streptomycin inhibited the formation of biofilm and eradicated the established mature biofilm. Streptomycin at sub-MIC was also capable of inhibiting biofilm formation on the urinary catheters. In addition, the sub-MIC of streptomycin attenuated the bacterial virulence properties as confirmed by both phenotypic and gene expression studies. The optimal conditions for streptomycin to perform anti-biofilm and anti-virulence activities were proposed as alkaline TSB media (pH 7.9) at 35 °C. However, sub-MIC of streptomycin also exhibited a comparative anti-biofilm efficacy in LB media at similar pH level and temperature. Furthermore, this condition also improved the biofilm inhibition and eradication properties of streptomycin, tobramycin and tetracycline towards the biofilm formed by a clinical isolate of P. aeruginosa. Findings from the present study provide an important insight for further studies on the mechanisms of biofilm inhibition and dispersion of pre-existing biofilm by streptomycin as well as tobramycin and tetracycline under a specific culture environment.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Estreptomicina/farmacologia , Virulência/efeitos dos fármacos , Catéteres/microbiologia , Meios de Cultura/química , Perfilação da Expressão Gênica , Concentração de Íons de Hidrogênio , Temperatura , Tetraciclina/farmacologia , Tobramicina/farmacologia , Fatores de Virulência/biossíntese
4.
Acc Chem Res ; 50(11): 2684-2692, 2017 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-28990760

RESUMO

Nanostructured materials such as porous metal oxides, metal nanoparticles, porous carbons, and their composites have been intensively studied due to their applications, including energy conversion and storage devices, catalysis, and gas storage. Appropriate precursors and synthetic methods are chosen for synthesizing the target materials. About a decade ago, metal-organic frameworks (MOFs) and coordination polymers (CPs) emerged as new precursors for these nanomaterials because they contain both organic and inorganic species that can play parallel roles as both a template and a precursor under given circumstances. Thermal conversions of MOFs offer a promising toolbox for synthesizing functional nanomaterials that are difficult to obtain using conventional methods. Although understanding the conversion mechanism is important for designing MOF precursors for the synthesis of nanomaterials with desired physicochemical properties, comprehensive discussions revealing the transformation mechanism remain insufficient. This Account reviews the utilization of MOFs/CPs as precursors and their transformation into functional nanomaterials with a special emphasis on understanding the relationship between the intrinsic nature of the parent MOFs and the daughter nanomaterials while discussing various experimental approaches based on mechanistic insights. We discuss nanomaterials categorized by materials such as metal-based nanomaterials and porous carbons. For metal-based nanomaterials transformed from MOFs, the nature of metal ions in the MOF scaffolds affects the physicochemical properties of the resultant materials including the phase, composite, and morphology of nanomaterials. Organic ligands are also involved in the in situ chemical reactions with metal species during thermal conversion. We describe these conversion mechanisms by classifying the phase of metal components in the resultant materials. Along with the metal species, carbon is a major element in MOFs, and thus, the appropriate choice of precursor MOFs and heat treatment can be expected to yield carbon-based nanomaterials. We address the relationship between the nature of the parent MOF and the porosity of the daughter carbon material-a controversial issue in the synthesis of porous carbons. Based on an understanding of the mechanism of MOF conversion, morphologically or compositionally advanced materials are synthesized by adopting appropriate MOF precursors and thermolysis conditions. Despite the progressive understanding of conversion phenomena of MOFs/CPs, this research field still has rooms to be explored and developed, ultimately in order to precisely control the properties of resultant nanomaterials. In this sense, we should pay more attention to the mechanism investigations of MOF conversion. We believe this Account will facilitate a deeper understanding of MOF/CP conversion routes and will accelerate further development in this field.

5.
Inorg Chem ; 55(4): 1920-5, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26819090

RESUMO

Flexible metal-organic frameworks (MOFs) show the structural transition phenomena, gate opening and breathing, upon the input of external stimuli. These phenomena have significant implications in their adsorptive applications. In this work, we demonstrate the direct capture of these gate-opening and breathing phenomena, triggered by CO2 molecules, in a well-designed flexible MOF composed of rotational sites and molecular gates. Combining X-ray single crystallographic data of a flexible MOF during gate opening/closing and breathing with in situ X-ray powder diffraction results uncovered the origin of this flexibility. Furthermore, computational studies revealed the specific sites required to open these gates by interaction with CO2 molecules.

6.
Pharm Biol ; 53(2): 212-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25243868

RESUMO

CONTEXT: Schizandra chinensis Baill (Magnoliaceae) fruit extract (SCE) is considered a traditional herbal medicine for the treatment and alleviation of various diseases. Gastric cancer is the second most common cause of cancer-related death worldwide, and the first most common in Korea. OBJECTIVES: This study investigates the mechanism of SCE-induced apoptosis in AGS human gastric cancer cells. MATERIALS AND METHODS: SCE concentrations from 100 to 400 µg/ml were used. Cell viabilities were determined using MTT assay. Members of the Bcl-2 family and Bax were detected by Western blotting. RT-PCR was performed to measure the expression level of the Fas/FasL pro-apoptotic genes. RESULTS: SCE inhibited the proliferation AGS cells for 24 or 72 h (inhibition by 3.1% ± 5.2% at 100 µg/ml and 87.3% ± 7.6% at 400 µg/ml at 24 h and by 40.2% ± 5.3% 100 µg/ml and 95.3% ± 1.3% 400 µg/ml at 72 h) and increased the sub-G1 phase (25.3% ± 5.2% at 100 µg/ml and 370.2% ± 7.2% at 400 µg/ml) and the mitochondrial membrane depolarization (11.2% ± 2.1% at 100 µg/ml and 311.5% ± 6.1% at 400 µg/ml). The SCE-induced apoptotic cell death showed the down-regulation of Bcl-2, but up-regulation of Bax. Subsequently, SCE increased the expression level of Fas/FasL, activated caspase-9 and -3, and increased reactive oxygen species generation. Also, JNK II inhibitor or a p38 MAPK inhibitor inhibited SCE-induced cell death. DISCUSSION AND CONCLUSION: These results indicate that SCE might be an effective chemotherapeutic for the treatment of human gastric cancer.


Assuntos
Apoptose/efeitos dos fármacos , MAP Quinase Quinase 4/metabolismo , Mitocôndrias/efeitos dos fármacos , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Schisandra/química , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ativação Enzimática , Frutas/química , Humanos , Mitocôndrias/metabolismo , Extratos Vegetais/isolamento & purificação , Transdução de Sinais , Neoplasias Gástricas/patologia
7.
Metabolites ; 14(5)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38786727

RESUMO

Soft tissue sarcoma (STS) is a relatively rare malignancy, accounting for about 1% of all adult cancers. It is known to have more than 70 subtypes. Its rarity, coupled with its various subtypes, makes early diagnosis challenging. The current standard treatment for STS is surgical removal. To identify the prognosis and pathophysiology of STS, we conducted untargeted metabolic profiling on pre-operative and post-operative plasma samples from 24 STS patients who underwent surgical tumor removal. Profiling was conducted using ultra-high-performance liquid chromatography-quadrupole time-of-flight/mass spectrometry. Thirty-nine putative metabolites, including phospholipids and acyl-carnitines were identified, indicating changes in lipid metabolism. Phospholipids exhibited an increase in the post-operative samples, while acyl-carnitines showed a decrease. Notably, the levels of pre-operative lysophosphatidylcholine (LPC) O-18:0 and LPC O-16:2 were significantly lower in patients who experienced recurrence after surgery compared to those who did not. Metabolic profiling may identify aggressive tumors that are susceptible to lipid synthase inhibitors. We believe that these findings could contribute to the elucidation of the pathophysiology of STS and the development of further metabolic studies in this rare malignancy.

8.
J Am Chem Soc ; 135(24): 8940-6, 2013 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-23651169

RESUMO

Nanoporous metal oxide materials are ubiquitous in the material sciences because of their numerous potential applications in various areas, including adsorption, catalysis, energy conversion and storage, optoelectronics, and drug delivery. While synthetic strategies for the preparation of siliceous nanoporous materials are well-established, nonsiliceous metal oxide-based nanoporous materials still present challenges. Herein, we report a novel synthetic strategy that exploits a metal-organic framework (MOF)-driven, self-templated route toward nanoporous metal oxides via thermolysis under inert atmosphere. In this approach, an aliphatic ligand-based MOF is thermally converted to nanoporous metal oxides with highly nanocrystalline frameworks, in which aliphatic ligands act as the self-templates that are afterward evaporated to generate nanopores. We demonstrate this concept with hierarchically nanoporous magnesia (MgO) and ceria (CeO2), which have potential applicability for adsorption, catalysis, and energy storage. The pore size of these nanoporous metal oxides can be readily tuned by simple control of experimental parameters. Significantly, nanoporous MgO exhibits exceptional CO2 adsorption capacity (9.2 wt %) under conditions mimicking flue gas. This MOF-driven strategy can be expanded to other nanoporous monometallic and multimetallic oxides with a multitude of potential applications.

9.
Cell Physiol Biochem ; 31(4-5): 542-54, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23571358

RESUMO

BACKGROUND/AIMS: In this study, we studied the effects of cholecystokinin (CCK) on pacemaker potentials in cultured interstitial cells of Cajal (ICCs) from mouse small intestine using the whole cell patch clamp technique. METHODS: ICCs are pacemaker cells that exhibit periodic spontaneous depolarization, which is responsible for the production of slow waves in gastrointestinal smooth muscle, and generate periodic pacemaker potentials in current-clamp mode. RESULTS: Exposure to CCK (100 nM-5 µM) decreased the amplitudes of pacemaker potentials and depolarized resting membrane potentials. To identify the type of CCK receptors involved in ICCs, we examined the effects of CCK agonists and found that the addition of CCK1 agonist (A-71323, 1 µM) depolarized resting membrane potentials, whereas exposure to CCK2 agonist (gastrin, 1 µM) had no effect on pacemaker potentials. To confirm these results, we examined the effects of CCK antagonists and found that pretreatment with CCK1 antagonist (SR 27897, 1 µM) blocked CCK-induced effects. However, pretreatment with CCK2 antagonist (LY 225910, 1 µM) did not. Furthermore, intracellular GDPßS suppressed CCK-induced effects. To investigate the involvements of phospholipase C (PLC), protein kinase C (PKC), and protein kinase A (PKA) in the effects of CCK in cultured ICCs, we used U-73122 (an active PLC inhibitor), chelerythrine (a PKC inhibitor), SQ-22536 (an inhibitor of adenylate cyclase), or mPKAI (an inhibitor of myristoylated PKA). All inhibitors blocked the CCK-mediated effects on pacemaker potentials. In addition, we found that transient receptor potential classical 5 (TRPC5) channel was involved in CCK-activated currents in cultured ICCs. CONCLUSION: These results suggest that the CCK induced depolarization of pacemaking activity occurs in a G-protein-, PLC-, PKC-, and PKA-dependent manner via CCK1 receptor and TRPC5 channel is a candidate for CCK-activated currents in cultured ICCs in murine small intestine. Therefore, the ICCs are targets for CCK and their interaction can affect intestinal motility.


Assuntos
Colecistocinina/farmacologia , Células Intersticiais de Cajal/metabolismo , Intestino Delgado/fisiologia , Potenciais da Membrana/efeitos dos fármacos , Animais , Células Cultivadas , Quimiocinas CC , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Estrenos/farmacologia , Gastrinas/farmacologia , Ácidos Indolacéticos/farmacologia , Células Intersticiais de Cajal/citologia , Intestino Delgado/citologia , Camundongos , Camundongos Endogâmicos BALB C , Técnicas de Patch-Clamp , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Pirrolidinonas/farmacologia , Quinazolinonas/farmacologia , Receptor de Colecistocinina B/agonistas , Receptor de Colecistocinina B/antagonistas & inibidores , Receptor de Colecistocinina B/metabolismo , Receptores da Colecistocinina/agonistas , Receptores da Colecistocinina/antagonistas & inibidores , Receptores da Colecistocinina/metabolismo , Canais de Cátion TRPC/metabolismo , Tiazóis/farmacologia , Fosfolipases Tipo C/antagonistas & inibidores , Fosfolipases Tipo C/metabolismo
10.
Inorg Chem ; 52(2): 589-95, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23270469

RESUMO

A luminescent lithium metal-organic framework (MOF) is constructed from the solvothermal reaction of Li(+) and a well-designed organic ligand, bis(4-carboxyphenyl)-N-methylamine (H(2)CPMA). A Li-based MOF can detect an explosive aromatic compound containing nitro groups as an explosophore, by showing a dramatic color change with concurrent luminescence quenching in the solid state. The detection sites are proven directly through single-crystal-to-single-crystal transformations, which show strong interactions between the aromatic rings of the electron-rich CPMA(2-) molecules and the electron-deficient nitrobenzene.

11.
Artigo em Inglês | MEDLINE | ID: mdl-37001203

RESUMO

Vitamin D is important because it has roles in maintaining musculoskeletal health, redox homeostasis, and the immune system; however, it is commonly dysregulated by endocrine disrupting chemicals, particularly phthalates and bisphenol A (BPA). Continuous exposure to phthalates and BPA may alter the endogenous metabolite profiles associated with vitamin D activity, although the specific metabolites are yet to be identified. In this study, we identified the endogenous metabolites altered by phthalates and BPA exposure through untargeted metabolic profiling and investigated the role of these metabolites in vitamin D activity. Plasma metabolic profiling using liquid chromatography-mass spectrometry was performed in two groups: severe 25-hydroxyvitamin D (25(OH)D) deficiency and high exposure to phthalates and BPA (Group A) and 25(OH)D deficiency and low exposure to phthalates and BPA (Group B). Multivariate analysis revealed a distinct separation between the two groups. A total of six metabolites were annotated, of which levels of two were significantly different between the two groups: platelet-activating factor (PAF) C16 or lysophosphatidylcholine (lysoPC) 18:0, and 11Z-eicosenamide. Plasma levels of PAF C16 or lysoPC 18:0 were increased in Group A and exhibited an area under the curve of 0.769 with an accuracy of 74.4% in a receiver operating characteristic curve analysis. These metabolites are generated as byproducts of lipid peroxidation, which supports the fact that phthalates and BPA induce oxidative stress in cells. Furthermore, PAF C16 and lysoPC 18:0 may be involved in the network that interferes with the antioxidant activity of vitamin D upon exposure to phthalates and BPA. This study results provide useful information on how the activity of vitamin D on the antioxidant system is inhibited when exposure to phthalates and BPA.


Assuntos
Antioxidantes , Ácidos Ftálicos , Humanos , Antioxidantes/farmacologia , Vitamina D , Compostos Benzidrílicos , Vitaminas , Cromatografia Líquida , Espectrometria de Massas
12.
Transl Clin Pharmacol ; 31(2): 105-113, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37440782

RESUMO

Two open-label, randomized, two-period crossover studies were conducted to investigate the pharmacokinetic (PK) properties, safety, and bioequivalence of the test formulation (KD4004), a new fixed-dose combination (FDC) formulation of dapagliflozin and metformin extended release (XR) tablets, relative to the reference formulation (10 mg dapagliflozin/1,000 mg metformin XR FDC tablet) in healthy subjects under fasting (Part A) and fed (Part B) conditions. After giving the dose, serial blood samples were collected for a period of 48 hours. Primary PK parameters (AUC0-t and Cmax) were used to assess bioequivalence between two dapagliflozin/metformin XR (10/1,000 mg) FDC formulations under fed and fasting conditions. Safety and tolerability were also evaluated. Part A and Part B were completed by 32 and 37 subjects, respectively. Bioequivalence of the two FDC formulations of dapagliflozin and metformin XR tablets was established in both the fasted and the fed conditions as the 90% confidence interval of the ratios of adjusted geometric means for AUC0-t and Cmax were contained within the predefined range of 0.800-1.250 bioequivalence criteria. Single-dose administration of dapagliflozin and metformin XR was safe and well tolerated as the two FDC formulations. In conclusion, both FDC formulations of dapagliflozin and metformin XR tablets were bioequivalent in fed and fasted subjects. All treatments were well tolerated. Trial Registration: Clinical Research Information Service Identifier: KCT0004026.

13.
Bioprocess Biosyst Eng ; 34(1): 113-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20640446

RESUMO

The marine alginate lyase from Streptomyces sp. ALG-5, which specifically degrades poly-G block of alginate, was functionally expressed as a His-tagged form with an Escherichia coli expression system. The recombinant alginate lyase expressed with pColdI at 15 °C exhibited the highest alginate-degrading activity. The recombinant alginate lyase was efficiently immobilized onto two types of magnetic nanoparticles, superparamagnetic iron oxide nanoparticle, and hybrid magnetic silica nanoparticle, based on the affinity between His-tag and Ni(2+) that displayed on the surfaces of nanoparticles. An alginate oligosaccharide mixture consisting of dimer and trimer was prepared by the immobilized alginate lyase. The immobilized enzymes were re-used repeatedly more than 10 times after magnetic separation.


Assuntos
Enzimas Imobilizadas/metabolismo , Escherichia coli/enzimologia , Polissacarídeo-Liases/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Streptomyces/enzimologia , Alginatos/metabolismo , Clonagem Molecular , Enzimas Imobilizadas/química , Escherichia coli/genética , Magnetismo , Nanopartículas/química , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/isolamento & purificação , Proteínas Recombinantes de Fusão/isolamento & purificação
14.
HERD ; 14(2): 16-29, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33745330

RESUMO

PURPOSE: The purpose of this article is to define design thinking, provide insights into how it may be integrated into the healthcare design process, and provide a checklist for future implementation. BACKGROUND: Design thinking is a collaborative method of inquiry that fosters innovative, team-generated solutions to complex scenarios, known as "wicked problems," that are extraordinarily difficult to solve. It is a practical tool in the toolbox of the codesign team, which includes the client and design professionals as primary stakeholders. It is powered by team-based creativity that adaptively responds to a need for new approaches and products in an innovative and practically applicable way. The need for design thinking in healthcare is steadily increasing as the healthcare system and its care environments continue to grow in complexity. Although major medical breakthroughs have undeniably expanded the average human life span, the current healthcare system is inefficient. Now, more than ever, design thinking and the innovative, human-centered solutions it enables are needed within healthcare design. Although the use of design thinking as a method within the field of architecture is not new, many design teams struggle integrating it fully within the design process, particularly in healthcare. The knowledge, design method, checklists, and direction provided in this article can benefit healthcare design teams to successfully integrate the method into practice. CONCLUSION: If design thinking is integrated into the healthcare architectural design process with the creative problem-solving method, opportunities will arise for innovative solutions and deeper insights into problems to benefit healthcare delivery.


Assuntos
Criatividade , Resolução de Problemas , Atenção à Saúde , Instalações de Saúde , Humanos , Projetos de Pesquisa
15.
Chem Commun (Camb) ; 57(57): 6960-6974, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34159973

RESUMO

Increasing the complexity of nanomaterials in terms of their structure and chemical composition has attracted significant attention, because it can yield unique scientific outcomes and considerable improvements for practical applications. Various approaches are being developed for the synthesis of nanostructured composites. Coordination polymers (CPs) emerged as new precursors in solid-state reactions for nanomaterials nearly two decades ago; the repetitively arranged inorganic and organic units can facilitate the production of nanoscale particles and porous carbon upon thermal decomposition. Metal-organic frameworks (MOFs), a subgroup of CPs featuring crystalline and porous structures, have subsequently become primary objects of interest in this field, as can be seen by the rapidly increasing number of reports on this topic. However, unique composite materials with increasingly complex nanostructures, which cannot be achieved via conventional methods, have been rarely realised, even though conventional MOF research has enabled the delicate control of structures at the molecular level and extensive applications as templates. In this regard, a comprehensive review of the fabrication strategies of MOF-based precursors and the thermal transformation into functional nanomaterials is provided herein, with a particular emphasis on the recent developments in nanocomposite research. We briefly introduce the roles and capabilities of MOFs in the synthesis of nanomaterials and subsequently discuss diverse synthetic routes for obtaining morphologically or compositionally advanced composite nanomaterials, based on our understanding of the MOF conversion mechanism.

16.
Food Sci Biotechnol ; 30(5): 765-771, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34025128

RESUMO

The present study aimed to evaluate the efficacy of a depuration system equipped with UV-irradiation to control Vibrio vulnificus infection such as septicemia (or sepsis) using alive oysters. After 6 h of bioaccumulation of V. vulnificus, Pacific oyster Crassostrea gigas were found to be contaminated by > 8.0 log MPN/g of V. vulnificus cells. After 60 h of depuration, the V. vulnificus cell number significantly decreased to < 4.0 log MPN/g. The present depuration process meets the standard effectiveness in reducing V. vulnificus cells by > 3.52 log and < 30 MPN/g as recommended by the National Shellfish Sanitization Procedure Molluscan Shellfish Control guidelines. Furthermore, no significant changes in pH value and glycogen content indicate that the depuration process did not affect the freshness and quality of the oyster samples. The present study could help control any potential infection associated with the consumption of raw oysters without losing their quality.

17.
J Microbiol Biotechnol ; 19(2): 161-6, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19307765

RESUMO

Certain microalgae have been known to use light and various carbon sources to produce carbohydrates, mainly in the form of starch. This is one of the pertinent feedstocks replacing agricultural products for the production of bioethanol by yeast. This study focuses upon dilute acid hydrothermal pretreatments at low cost and high efficiency to compete with current methods, and employs Chlamydomonas reinhardtii UTEX 90 as the feedstock. With dry cells of 5% (w/v), the algal biomass was pretreated with sulfuric acid (1-5%) under temperatures from 100 to 120oC, from 15 to 120 min. As a result, the glucose release from the biomass was maximum at 58% (w/w) after pretreatment with 3% sulfuric acid at 110 degrees for 30 min. This method enabled not only starch, but also the hydrolysis of other oligosaccharides in the algal cell in high efficiency. Arrheniustype of model equation enabled extrapolation of some yields of glucose beyond this range. The pretreated slurry was fermented by yeast, Saccharomyces cerevisiae S288C, resulting in an ethanol yield of 29.2% from algal biomass. This study suggests that the pretreated algal biomass is a suitable feedstock for ethanol production and can have a positive impact on large-scale applied systems.


Assuntos
Biomassa , Chlamydomonas reinhardtii/metabolismo , Etanol/metabolismo , Ácidos Sulfúricos/farmacologia , Animais , Reatores Biológicos , Chlamydomonas reinhardtii/efeitos dos fármacos , Fermentação , Glucose/metabolismo , Temperatura Alta , Saccharomyces cerevisiae/metabolismo
18.
Chem Commun (Camb) ; 55(60): 8832-8835, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31150029

RESUMO

An isostructural series of flexible metal-organic frameworks based on macrocycles having diverse pendant arms was developed to tune flexibility depending on functional groups. The pendant arms directing into the pores were found to play a key role in imparting different gate-opening behaviours in the threshold pressure and sorption capacity upon interaction with guest molecules.

19.
Nat Commun ; 10(1): 3620, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399593

RESUMO

Composite metal-organic frameworks (MOFs) tend to possess complex interfaces that prevent facile and rational design. Here we present a joint computational/experimental workflow that screens thousands of MOFs and identifies the optimal MOF pairs that can seamlessly connect to one another by taking advantage of the fact that the metal nodes of one MOF can form coordination bonds with the linkers of the second MOF. Six MOF pairs (HKUST-1@MOF-5, HKUST-1@IRMOF-18, UiO-67@HKUST-1, PCN-68@MOF-5, UiO-66@MIL-88B(Fe) and UiO-67@MIL-88C(Fe)) yielded from our theoretical predictions were successfully synthesized, leading to clean single crystalline MOF@MOF, demonstrating the power of our joint workflow. Our work can serve as a starting point to accelerate the discovery of novel MOF composites that can potentially be used for many different applications.

20.
Cancer Sci ; 99(12): 2502-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19032368

RESUMO

Ca2+ and Mg2+ have a fundamental role in many cellular processes and ion channels are involved in normal physiologic processes and in the pathology of various diseases. The aim here was to show that the presence and potential role of transient receptor potential melastatin 7 (TRPM7) channels in the growth and survival of AGS cells, the most common human gastric adenocarcinoma cell line. The patch-clamp technique for whole-cell recording was used in AGS cells. TRPM7-specific small interfering RNAs were used for specific inhibition of TRPM7. Whole-cell voltage-clamp recordings revealed the TRPM7-like currents that activated spontaneously following loss of intracellular Mg2+. The current had a non-linear current-voltage relationship with the characteristic steep outward rectification associated with TRPM7 channels. Reverse transcription-polymerase chain reaction, western blotting, and immunoreactivity all showed abundant expression of TRPM7 messenger RNA and protein in AGS cells. Transfection of AGS cells with TRPM7 siRNA significantly reduced the expression of TRPM7 mRNA and protein as well as the amplitude of the TRPM7-like currents. Furthermore, we found that Mg2+ is critical for the growth and survival in AGS cells. Blockade of TRPM7 channels by La3+ and 2-APB or suppression of TRPM7 expression by siRNA inhibited the growth and survival of these cells. Human gastric adenocarcinoma cells express TRPM7 channel whose presence is essential for cell survival. The protein is a likely potential target for the pharmacological treatment of gastric cancer.


Assuntos
Neoplasias Gástricas/genética , Canais de Cátion TRPM/antagonistas & inibidores , Canais de Cátion TRPM/genética , Dedos de Zinco/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Caspase 3/análise , Caspase 3/metabolismo , Morte Celular/genética , Linhagem Celular Tumoral , Eletrofisiologia , Formazans/análise , Formazans/metabolismo , Humanos , Imuno-Histoquímica , Técnicas de Patch-Clamp , Proteínas Serina-Treonina Quinases , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Neoplasias Gástricas/patologia , Sais de Tetrazólio/análise , Sais de Tetrazólio/metabolismo
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