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1.
Plants (Basel) ; 10(9)2021 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-34579376

RESUMEN

Crop production under hydroponic environments has many advantages, yet the effects of solution flow rate on plant growth remain unclear. We conducted a hydroponic cultivation study using different flow rates under light-emitting diode lighting to investigate plant growth, nutrient uptake, and root morphology under different flow rates. Swiss chard plants were grown hydroponically under four nutrient solution flow rates (2 L/min, 4 L/min, 6 L/min, and 8 L/min). After 21 days, harvested plants were analyzed for root and shoot fresh weight, root and shoot dry weight, root morphology, and root cellulose and hemicellulose content. We found that suitable flow rates, acting as a eustress, gave the roots appropriate mechanical stimulation to promote root growth, absorb more nutrients, and increase overall plant growth. Conversely, excess flow rates acted as a distress that caused the roots to become compact and inhibited root surface area and root growth. Excess flow rate thereby resulted in a lower root surface area that translated to reduced nutrient ion absorption and poorer plant growth compared with plans cultured under a suitable flow rate. Our results indicate that regulating flow rate can regulate plant thigmomorphogenesis and nutrient uptake, ultimately affecting hydroponic crop quality.

2.
Int J Pharm ; 563: 413-425, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-30953764

RESUMEN

The aim of this study is to establish a contamination-free milling method using ice beads instead of conventional hard beads such as metal or ceramics. Ice beads, which melt after the milling process to form water, would solve the contamination issue attributed to bead breakage or abrasion. The technique/method for preparing spherical ice beads of mono-dispersed size ranging from 150 to 3000 µm was newly developed. An oscillation beads milling apparatus was used for pulverization. In the initial stages of ice beads milling, the process is dry, but as time passes, the surface of the ice beads begins to melt, resulting in a transition to wet beads milling. It was found that ice beads are an effective milling media for beads milling, and that milling efficiency is strongly affected by the temperature of the coolant, with the peak efficiency occurring when the temperature was set to -2 °C and ice beads around 1500 µm in diameter were used. The spray-dried powder obtained from suspension after ice beads milling had dissolution improvement equivalent to that obtained after zirconia beads milling, resulting from its spontaneous rapid dispersion into nanosuspension.


Asunto(s)
Composición de Medicamentos/métodos , Hielo , Fenitoína/química , Desecación , Liberación de Fármacos , Povidona/química , Dodecil Sulfato de Sodio/química , Solubilidad , Agua/química , Circonio
3.
Cancer Med ; 6(6): 1255-1263, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28544821

RESUMEN

Microsatellite instability (MSI) is an important biomarker for screening for Lynch syndrome, and also of response to immune checkpoint inhibitors. The aim of this study is to create a predictive model to determine which elderly patients with colorectal cancer (CRC) should undergo MSI and/or immunohistochemistry testing on the basis of clinicopathological data. We analyzed a test cohort of CRC patients aged ≥50 years (n = 2219) by multivariate logistic regression analyses to identify predictors of high-frequency MSI (MSI-H). The created prediction model was validated in an external cohort (n = 992). The frequency of MSI-H was 5.5% among CRC patients aged ≥ 50 years. The following five predictors of MSI-H were identified in the test cohort: female (1 point), mucinous component (2 points), tumor size ≥ 60 mm (2 points), location in proximal colon (3 points), and BRAF mutation (6 points). The area under curve (AUC) in the receiver-operating characteristic (ROC) analysis of this prediction model was 0.832 (95% confidence interval: 0.790-0.874). The sensitivity and specificity were 74.4% and 77.7%, respectively, for a cut-off score of 4 points. The receiver-operating characteristic curve of the validation cohort also showed an AUC of 0.856 (95% CI: 0.806-0.905). This prediction model is useful to select elderly CRC patients who should undergo MSI testing, and who may benefit from treatment with 5-FU-based adjuvant chemotherapy and cancer immunotherapy.


Asunto(s)
Neoplasias Colorrectales/genética , Inestabilidad de Microsatélites , Modelos Biológicos , Anciano , Neoplasias Colorrectales/patología , Metilación de ADN , Femenino , Humanos , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL/genética , Mutación , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Reproducibilidad de los Resultados , Carga Tumoral
4.
Oncol Rep ; 37(2): 785-792, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28000889

RESUMEN

Genetic testing is needed for the treatment of colorectal cancer (CRC), especially molecular-targeted therapy. The effects of anti-EGFR therapy and prognosis are affected by the presence of KRAS mutations. However, whether primary CRC or metastatic tissues are appropriate in the analysis is still unclear. In the present study, we assessed the concordance of KRAS/BRAF mutation status and microsatellite instability (MSI) in primary CRC and corresponding metastases. This study enrolled 457 patients with surgically resected primary and corresponding metastatic CRC (499 synchronous metastases and 57 metachronous metastases) and seven local recurrences, and KRAS/BRAF mutation and MSI status were analysed for these tumours. The concordance rates of KRAS mutation, BRAF mutation, wild-type, MSI-H and MSS between primary CRC and corresponding metastases were 93.9% (214/228), 100% (30/30), 99.3% (304/306), 87.5% (21/24) and 100% (137/137), respectively. These high concordance rates were not different between synchronous and metachronous metastases. In conclusion, a high concordance of KRAS/BRAF mutation status and MSI status was observed between primary CRC and corresponding metastases in this study. Either primary CRC or metastatic tissues can be used for testing KRAS/BRAF mutation status and MSI status.


Asunto(s)
Neoplasias Colorrectales/genética , Inestabilidad de Microsatélites , Mutación/genética , Neoplasias Primarias Múltiples/genética , Neoplasias Primarias Secundarias/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Biomarcadores de Tumor/genética , Estudios de Casos y Controles , Neoplasias Colorrectales/patología , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Metástasis Linfática , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/secundario , Estadificación de Neoplasias , Neoplasias Primarias Múltiples/secundario , Neoplasias Primarias Secundarias/secundario , Neoplasias Peritoneales/genética , Neoplasias Peritoneales/secundario , Pronóstico
5.
Anticancer Res ; 37(1): 239-247, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28011498

RESUMEN

BACKGROUND: A recent clinical trial on the immune check-point inhibitor pembrolizumab demonstrated that microsatellite instability (MSI) is a good biomarker for response to this inhibitor. However, clinicopathological features of advanced colorectal cancer (CRC) with high-frequency MSI (MSI-H) are unclear. PATIENTS AND METHODS: A total of 2,439 surgically resected CRC tissues were analyzed for MSI status, and mutational status of V-Ki-Ras2 Kirsten rat sarcoma 2 viral oncogene homolog (KRAS), neuroblastoma RAS viral oncogene homolog (NRAS) and v-Raf murine sarcoma viral oncogene homolog B (BRAF). Stage IV cases were selected, and clinical and molecular features were evaluated. RESULTS: There was no significant survival difference observed between MSI-H CRC and microsatellite-stable (MSS) CRC in patients with stage IV disease (3.92 vs. 2.50 years; p=0.766). However, hematogenous and lymphogenous metastasis-dominant CRC with MSI-H demonstrated poor prognosis, whereas peritoneal metastasis-dominant CRC with MSI-H demonstrated good prognosis, (1.33 vs. 5.2 years; p=0.006). CONCLUSION: Prognosis of stage IV CRC with MSI-H depended on the metastatic pattern. These findings provide useful information for the adaptation of CRC immunotherapy.


Asunto(s)
Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Inestabilidad de Microsatélites , Adulto , Anciano , Femenino , GTP Fosfohidrolasas/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Metástasis Linfática , Masculino , Proteínas de la Membrana/genética , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL/genética , Mutación , Estadificación de Neoplasias , Neoplasias Peritoneales/genética , Neoplasias Peritoneales/secundario , Pronóstico , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética
6.
Bioorg Med Chem ; 20(22): 6583-8, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23063519

RESUMEN

A toxic protein, dubbed molybdophyllysin, was isolated from the tropical toadstool Chlorophyllum molybdites by following its lethal effect in mice. Analysis of the protein using SDS-PAGE revealed a single 23-kDa band. Sequence analysis of molybdophyllysin tryptic fragments showed that this protein is highly homologous to metalloendopeptidases (MEPs) obtained from edible mushrooms, such as Grifola frondosa, Pleurotus ostreatus, and Armillaria mellea. These proteins include a HEXXH+D zinc-binding motif known as aspzincin. Accordingly, molybdophyllysin is a member of the deuterolysin family of zinc proteases. Molybdophyllysin retained its proteolytic activity at temperatures up to 60°C with an optimum pH of 7.0. The activity was inhibited by both 1,10-phenanthroline and N-bromosuccinimide, but molybdophyllysin exhibited strong resistance to SDS.


Asunto(s)
Agaricales/enzimología , Metaloendopeptidasas/metabolismo , Secuencia de Aminoácidos , Animales , Bromosuccinimida/química , Concentración de Iones de Hidrógeno , Metaloendopeptidasas/antagonistas & inhibidores , Metaloendopeptidasas/química , Metaloendopeptidasas/aislamiento & purificación , Ratones , Datos de Secuencia Molecular , Fenantrolinas/química , Homología de Secuencia de Aminoácido , Temperatura , Zinc/química , Zinc/metabolismo
7.
Int J Biol Macromol ; 50(1): 236-44, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22085752

RESUMEN

A sheath-forming sulfa oxidizer, Thiothrix nivea, was mixotrophically cultured in a medium supplemented with acetic acid and sodium disulfide. Its sheath, a microtube-like extracellular supermolecule, was prepared by selectively removing the cells with lysozyme, sodium dodecyl sulfate, and sodium hydroxide. The sheath was not visibly affected by hydrazine treatment, suggesting that it is not a proteinous supermolecule. From the acid hydrolysate of the sheath, glucose and glucosamine were detected in an approximate molar ratio of 1:1. Three other saccharic compounds were detected and recovered by HPLC as fluorescent derivatives prepared by reaction with 4-aminobenzoic acid ethyl ester. Nuclear magnetic resonance (NMR) analysis suggested that one of the derivatives was derived from an unidentified deoxypentose. NMR analysis for the other 2 derivatives showed that they were derived from ß-1,4-linked disaccharides and tetrasaccharides, which were composed of glucose and glucosamine. The sheath was readily broken down by weak HCl treatment, releasing an unidentified deoxypentose and polymer. Chemical analysis showed the presence of ß-1,4-linked D-Glcp and D-GlcNp in the polymer. NMR analysis revealed that the polymer had a repeating unit of →4)-D-Glcp-(ß1→4)-D-GlcNp-(ß1→. The solid-state 1D-(13)C NMR spectrum of the polymer in N-acetylated form supported this result. The molecular weight of the polymer was estimated to be 8.2×10(4) by size exclusion chromatography. Based on these results, the sheath of T. nivea is hypothesized to be assembled from alternately ß-1,4-linked glucosaminoglucan grafted with unidentified deoxypentose.


Asunto(s)
Glicosaminoglicanos/química , Polisacáridos Bacterianos/química , Thiothrix/metabolismo , Carbohidratos/química , Cromatografía/métodos , Cromatografía Líquida de Alta Presión/métodos , Medios de Cultivo/metabolismo , Glucosamina/química , Glucosa/química , Ácido Clorhídrico/química , Espectroscopía de Resonancia Magnética/métodos , Metilación , Microscopía Electrónica de Rastreo/métodos , Polímeros/química , Polisacáridos/química
8.
Int J Biol Macromol ; 48(2): 256-62, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21095202

RESUMEN

A typical filamentous bacterium, Sphaerotilus natans, secretes a thiolic glycoconjugate which is assembled into a microtube, so called sheath. The glycoconjugate is known to consist of a pentasaccharide-dipeptide repeating unit, but its chemical structure has not been completely elucidated. In order to determine its chemical structure, the sheath was broken down by performic acid oxidation. The released sulfonated derivative was water soluble which was suitable for detailed NMR analysis. The data exhibited the presence of two stoichiometric and one substoichiometric (relative abundance was about 0.5) acetylations, suggesting that the glycoconjugate is composed of two equimolar pentasaccharide-dipeptide repeating units each having either two or three acetyl groups. However, the position of substoichiometric acetylation could not be defined. To determine the position, the sheath was derivatized with a thiol selective fluorescent reagent followed by digestion with a specific polysaccharide lyase prepared from a sheath-degrading bacterium, Paenibacillus koleovorans. As expected, two fluorescent digests were recovered by reverse-phase HPLC and were subjected to NMR analysis. The data revealed that both digests are pentasaccharide-dipeptides which have unsaturated glucuronic acid and galactosamine residues at their reducing and non-reducing ends, respectively. It was also confirmed that one digest has 3-O-acetylated glucose residue while the other has non-derivatized glucose residue. The substoichiometric acetylation was thus identified with the 3-O-acetylation, and structural determination of the thiolic glycoconjugate was completed. By virtue of the clarification of the two digests' structures, the cleavage site was specified as (1→4)-α-galactosaminic bond to glucuronic acid. Based on the present and earlier findings, we propose a novel glycoconjugate category named thiopeptidoglycan and a novel polysaccharide lyase named thiopeptidoglycan lyase.


Asunto(s)
Glicopéptidos/análisis , Peptidoglicano/análisis , Polisacárido Liasas/metabolismo , Polisacáridos Bacterianos/análisis , Conformación de Carbohidratos , Secuencia de Carbohidratos , Cromatografía Líquida de Alta Presión , Glicopéptidos/química , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Paenibacillus/enzimología , Peptidoglicano/química , Polisacárido Liasas/aislamiento & purificación , Polisacáridos Bacterianos/química , Solubilidad , Sphaerotilus/química
9.
Phytochemistry ; 71(5-6): 648-57, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20096904

RESUMEN

Ingestion of the toxic mushroom Boletus venenatus causes a severe gastrointestinal syndrome, such as nausea, repetitive vomiting, diarrhea, and stomachache. A family of isolectins (B. venenatus lectins, BVLs) was isolated as the toxic principles from the mushroom by successive 80% ammonium sulfate-precipitation, Super Q anion-exchange chromatography, and TSK-gel G3000SW gel filtration. Although BVLs showed a single band on SDS-PAGE, they were further divided into eight isolectins (BVL-1 to -8) by BioAssist Q anion-exchange chromatography. All the isolectins showed lectin activity and had very similar molecular weights as detected by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis. Among them, BVL-1 and -3 were further characterized with their complete amino acid sequences of 99 amino acids determined and found to be identical to each other. In the hemagglutination inhibition assay, both proteins failed to bind to any mono- or oligo-saccharides tested and showed the same sugar-binding specificity to glycoproteins. Among the glycoproteins examined, asialo-fetuin was the strongest inhibitor. The sugar-binding specificity of each isolectin was also analyzed by using frontal affinity chromatography and surface plasmon resonance analysis, indicating that they recognized N-linked sugar chains, especially Galbeta1-->4GlcNAcbeta1-->4Manbeta1-->4GlcNAcbeta1-->4GlcNAc (Type II) residues in N-linked sugar chains. BVLs ingestion resulted in fatal toxicity in mice upon intraperitoneal administration and caused diarrhea upon oral administration in rats.


Asunto(s)
Agaricales/química , Lectinas/aislamiento & purificación , Lectinas de Plantas/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Asialoglicoproteínas , Carbohidratos/química , Diarrea/inducido químicamente , Electroforesis en Gel de Poliacrilamida , Fetuínas , Glicoproteínas/química , Lectinas/química , Lectinas/toxicidad , Ratones , Micotoxinas/química , Micotoxinas/aislamiento & purificación , Micotoxinas/toxicidad , Lectinas de Plantas/química , Lectinas de Plantas/toxicidad , Ratas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , alfa-Fetoproteínas
10.
Int J Biol Macromol ; 46(2): 206-11, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-20026345

RESUMEN

The sheath of Leptothrix cholodnii is constructed from a structural glycoconjugate, a straight-chained amphoteric heteropolysaccharide modified with glycine and cysteine. Though the structure of the glycan core is already determined, its modifications with amino acids and other molecules are not fully resolved. In this study, we aimed to determine the chemical structure of the glycoconjugate as a whole. Enantiomeric determination of cysteine in the sheath was performed and as a result, L-cysteine was detected. NMR spectroscopy was endeavored to determine overall structure of the glycoconjugate. Prior to NMR analysis, solubilization of the glycoconjugate was attempted by adding denaturing reagents or by derivatization. As far as tested, sulfonation by performic acid oxidation was suitable for solubilization, but further improvement was achieved by N-acetylation. The approximate molecular weight of the derivative was estimated to be 4.5 x 10(4) by size-exclusion chromatography. The NMR studies for the sulfonated glycoconjugate and its N-acetylated derivative revealed that the sheath glycoconjugate is a glycosaminoglycan consisting of a pentasaccharide repeating unit which is substoichiometrically esterified with 3-hydroxypropionic acid and stoichiometrically amidated with acetic acid and glycyl-L-cysteine.


Asunto(s)
Glicoconjugados/química , Leptothrix/química , Acetilación , Aminoácidos/análisis , Cisteína/química , Glicoconjugados/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Solubilidad , Estereoisomerismo , Sulfatos/metabolismo
11.
Phytochemistry ; 68(6): 893-8, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17254619

RESUMEN

A toxic protein, called bolevenine, was isolated from the toxic mushroom Boletus venenatus based on its lethal effects on mice. On SDS-PAGE, in either the presence or absence of 2-mercaptoethanol, this protein showed a single band of approximately 12 kDa. In contrast, based on gel filtration and MALDI-TOFMS, its relative molecular mass was estimated to be approximately 30 kDa and approximately 33 kDa, respectively, indicating that the protein consists of three identical subunits. This toxin exhibited its lethal activity following injection at 10mg/kg into mice. The N-terminal amino acid sequence was determined up to 18, and found to be similar to the previously reported bolesatine, a toxic compound isolated from Boletus satanas.


Asunto(s)
Agaricales/química , Proteínas Fúngicas/toxicidad , Micotoxinas/toxicidad , Secuencia de Aminoácidos , Animales , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Femenino , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica , Ratones , Datos de Secuencia Molecular , Micotoxinas/aislamiento & purificación , Micotoxinas/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Pruebas de Toxicidad/métodos
12.
Eur J Dermatol ; 14(4): 247-54, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15319158

RESUMEN

Finasteride is a type 2 5 alpha-reductase inhibitor that inhibits conversion of testosterone to dihydrotestosterone, a key mediator of male pattern hair loss (androgenetic alopecia). The objective of this study was to identify the optimal dosage of finasteride and to evaluate its efficacy and safety in the treatment of Japanese men with male pattern hair loss. In this double- blind randomized study, 414 Japanese men with male pattern hair loss received finasteride 1 mg (n = 139), finasteride 0.2 mg (n = 137), or placebo (n = 38) once daily for 48 weeks. Efficacy was evaluated by global photographic assessment, patient self-assessment, and investigator assessment. All efficacy endpoints showed significant improvement with finasteride therapy by 12 weeks (p < 0.05 versus placebo). At 48 weeks, 58%, 54%, and 6% of men in the finasteride 1 mg, finasteride 0.2 mg, and placebo groups, respectively, had improved based on assessments of global photographs. All efficacy endpoints were numerically superior for the 1 mg dose over the 0.2 mg dose at 48 weeks. Finasteride treatment was generally well tolerated. Finasteride 1 mg\day slows hair loss and improves hair growth in Japanese men with male pattern hair loss.


Asunto(s)
Inhibidores de 5-alfa-Reductasa , Alopecia/tratamiento farmacológico , Inhibidores Enzimáticos/uso terapéutico , Finasterida/uso terapéutico , Adulto , Alopecia/patología , Método Doble Ciego , Inhibidores Enzimáticos/administración & dosificación , Finasterida/administración & dosificación , Humanos , Japón , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
13.
J Am Acad Dermatol ; 46(6): 827-33, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12063478

RESUMEN

BACKGROUND: Ofuji's disease, also referred to as classic eosinophilic pustular folliculitis, is a rare dermatosis of unknown origin for which there is no uniformly effective treatment. OBJECTIVES AND METHODS: Twenty patients with Ofuji's disease (classic eosinophilic pustular folliculitis) evaluated in our department from January 1978 to June 1999 were studied clinically and histopathologically. Laboratory data, treatments, and clinical courses were evaluated in 12 of these individuals. RESULTS: Nissl modified staining revealed moderate increases of mast cells around hair follicles and sebaceous glands in all 20 patients; the majority of the infiltrating mast cells were tryptase-positive and chymase-negative. Eight of 11 patients treated with oral indomethacin responded completely. CONCLUSIONS: Indomethacin is an effective therapy for Ofuji's disease. Tryptase-positive and chymase-negative mast cells might play some role in the pathogenesis of Ofuji's disease.


Asunto(s)
Dermatosis Facial/epidemiología , Dermatosis Facial/etiología , Foliculitis/epidemiología , Foliculitis/etiología , Adolescente , Adulto , Antiinflamatorios no Esteroideos/uso terapéutico , Brazo , Dorso , Dapsona/uso terapéutico , Dermatosis Facial/tratamiento farmacológico , Dermatosis Facial/patología , Femenino , Foliculitis/tratamiento farmacológico , Foliculitis/patología , Pie , Humanos , Inmunohistoquímica , Indometacina/uso terapéutico , Japón/epidemiología , Masculino , Mastocitos/inmunología , Persona de Mediana Edad , Minociclina/uso terapéutico , Prednisolona/uso terapéutico , Sulfametoxazol/uso terapéutico , Tórax , Resultado del Tratamiento
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