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1.
ACS Chem Biol ; 19(4): 861-865, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38568215

RESUMEN

Eremophilanes exhibit diverse biological activities and chemical structures. This study reports the bioinformatics-guided reconstitution of the biosynthetic machinery of fungal eremophilanes, eremofortin C and sporogen-AO1, to elucidate their biosynthetic pathways. Their biosyntheses include P450-catalyzed multistep oxidation and enzyme-catalyzed isomerization by the DUF3237 family protein. Successful characterization of six P450s enabled us to discuss the functions of eremophilane P450s in putative eremophilane biosynthetic gene clusters, providing opportunities to understand the oxidative modification pathways of fungal eremophilanes.


Asunto(s)
Sesquiterpenos , Oxidación-Reducción , Sesquiterpenos Policíclicos , Sesquiterpenos/química , Hongos/química , Hongos/metabolismo , Vías Biosintéticas , Biología Computacional/métodos
2.
Case Rep Orthop ; 2019: 1893042, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31612090

RESUMEN

Axial alignment of the femur and tibia is often misdiagnosed in patients with patellofemoral stability problems. Femoral torsion is critical for patellofemoral biomechanics, so it must be evaluated in every patient before the plan of surgery is decided. This case describes a femoral derotational osteotomy due to excessive internal torsion of the femur fixed with a retrograde femoral nail. This type of fixation provides a biomechanical advantage compared to plates. At the two-year follow-up, the patient achieved excellent results, reaching a functional score of 91 points on the Lysholm scale. Derotational femoral osteotomy should be considered in patellofemoral pathology, and a retrograde femoral nail is a valid fixation method for this surgery.

3.
J Vis Exp ; (151)2019 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-31545323

RESUMEN

We present a high-performance source of unconditional polarization-entangled photons that have a high-emission rate, a broadband distribution, are degenerated and postselection free. The property of the source is based on the multiple quantum interference effect with a round-trip configuration of a Sagnac interferometer. The quantum interference effects make it possible to use the high generation efficiency of the polarization-entangled photons to process parametric down-conversion, and separate degenerated photon pairs into different optical modes without a postselection requirement. The principle of the optical system was described and experimentally used to measure the fidelity and Bell parameters, and also to characterize the generated polarization-entangled photons from a minimum of six combinations of polarization correlated data. The experimentally obtained fidelity and Bell parameters exceeded the classical local correlation limit and are clear evidence of the generation of unconditional polarization-entangled photons.


Asunto(s)
Interferometría/instrumentación , Fotones , Iluminación , Teoría Cuántica
4.
Appl Environ Microbiol ; 85(15)2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31101615

RESUMEN

Basidiomycete fungi are an attractive resource for biologically active natural products for use in pharmaceutically relevant compounds. Recently, genome projects on mushroom fungi have provided a great deal of biosynthetic gene cluster information. However, functional analyses of the gene clusters for natural products were largely unexplored because of the difficulty of cDNA preparation and lack of gene manipulation tools for basidiomycete fungi. To develop a versatile host for basidiomycete genes, we examined gene expression using genomic DNA sequences in the robust ascomycete host Aspergillus oryzae, which is frequently used for the production of metabolites from filamentous fungi. Exhaustive expression of 30 terpene synthase genes from the basidiomycetes Clitopilus pseudo-pinsitus and Stereum hirsutum showed two splicing patterns, i.e., completely spliced cDNAs giving terpenes (15 cases) and mostly spliced cDNAs, indicating that A. oryzae correctly spliced most introns at the predicted positions and lengths. The mostly spliced cDNAs were expressed after PCR-based removal of introns, resulting in the successful production of terpenes (14 cases). During this study, we observed relatively frequent mispredictions in the automated program. Hence, the complementary use of A. oryzae expression and automated prediction will be a powerful tool for genome mining.IMPORTANCE The recent large influx of genome sequences from basidiomycetes, which are prolific producers of bioactive natural products, may provide opportunities to develop novel drug candidates. The development of a reliable expression system is essential for the genome mining of natural products because of the lack of a tractable host for heterologous expression of basidiomycete genes. For this purpose, we applied the ascomycete Aspergillus oryzae system for the direct expression of fungal natural product biosynthetic genes from genomic DNA. Using this system, 29 sesquiterpene synthase genes and diterpene biosynthetic genes for bioactive pleuromutilin were successfully expressed. Together with the use of computational tools for intron prediction, this Aspergillus oryzae system represents a practical method for the production of basidiomycete natural products.


Asunto(s)
Transferasas Alquil y Aril/metabolismo , Aspergillus oryzae/metabolismo , Basidiomycota , Eurotiales/metabolismo , Genes Fúngicos , Terpenos/metabolismo , Basidiomycota/genética , Microorganismos Modificados Genéticamente/metabolismo , Familia de Multigenes
5.
J Am Chem Soc ; 140(39): 12392-12395, 2018 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-30226766

RESUMEN

Abscisic acid (ABA) is a well-known phytohormone that regulates abiotic stresses. ABA produced by fungi is also proposed to be a virulence factor of fungal pathogens. Although its biosynthetic pathway in fungi was proposed by a series of feeding experiments, the enzyme catalyzing the reaction from farnesyl diphosphate to α-ionylideneethane remains to be identified. In this work, we identified the novel type of sesquiterpene synthase BcABA3 and its unprecedented three-step reaction mechanism involving two neutral intermediates, ß-farnesene and allofarnesene. Database searches showed that BcABA3 has no homology with typical sesquiterpene synthases and that the homologous enzyme genes are found in more than 100 bacteria, suggesting that these enzymes form a new family of sesquiterpene synthases.


Asunto(s)
Ácido Abscísico/biosíntesis , Transferasas Alquil y Aril/metabolismo , Hongos/metabolismo , Transferasas Alquil y Aril/genética , Catálisis , Hongos/enzimología , Hongos/genética , Cromatografía de Gases y Espectrometría de Masas , Ligasas/genética , Ligasas/metabolismo , Sesquiterpenos/metabolismo
6.
Case Rep Orthop ; 2017: 4696014, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28487799

RESUMEN

Acute septic arthritis is a common clinical problem in emergency departments. Primary meningococcal arthritis (PMA) is very rare and few cases are reported in literature. D. B. M. consulted the emergency department for knee pain and fever; analysis showed that the cause was a Neisseria meningitidis type C infection. He received a treatment consisting of 2 arthroscopies and 5 weeks of antibiotics. At five weeks he returned to work and at 2 months he resumed sports (jogging and soccer) without complaints. Primary arthritis of the knee caused by Neisseria meningitidis is very rare. It has a very good response to antibiotics and arthroscopy procedure. Short-term follow-up and functional results are often good or excellent.

7.
Biofouling ; 26(7): 851-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20938849

RESUMEN

Bacterial attachment and growth on material surfaces are considered to be the primary steps leading to the formation of biofilm. Biofilms in hospital and food processing settings can result in bacterial infection and food contamination, respectively. Prevention of bacterial attachment, therefore, is considered to be the best strategy for abating these menaces and therefore the development of antibacterial metals becomes important. In this study, nine pure metals, viz. titanium, cobalt, nickel, copper, zinc, zirconium, molybdenum, tin, and lead have been tested for their antibacterial properties against two bacterial strains, Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. This was accomplished using two assay methods, the film contact method and the shaking flask method. The results show that the antibacterial properties varied significantly with different metals and the effectiveness of metals to resist bacterial attachment varied with the bacterial strain. Among the metals tested, titanium and tin did not exhibit antibacterial properties. TEM images showed that metal accumulation resulted in the disruption of the bacterial cell wall and other cellular components.


Asunto(s)
Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Metales Pesados/farmacología , Staphylococcus aureus/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Pared Celular/efectos de los fármacos , Medios de Cultivo , Escherichia coli/crecimiento & desarrollo , Escherichia coli/ultraestructura , Pruebas de Sensibilidad Microbiana/métodos , Microscopía Electrónica de Transmisión , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/ultraestructura
8.
Hum Cell ; 18(1): 59-65, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16130901

RESUMEN

We succeeded in primary culture of 3 in 4 cases of glioblastomas. The long-term passage cultures were not done from the primary cultures of original tumor, but glioblastoma cell line (HUBT-n) was established from a xenograft of nude mouse. This line grew well without interruption for 4 years and was subcultivated over 120 times. The cells were spindle like or round in shape and neoplastic and pleomorphic features contained glial fibrillar acid protein (GFAP) and S-100 protein and grew multilayering without contact inhibition. A bough-shaped long projection was noted from a small cell. One of the characteristics of the HUBT-n cells was existence of well developed intermediate filaments in their cytoplasm. The cells proliferated rapidly, and the population doubling time was about 32 hours. The chromosome number showed a narrow distribution of diploid range. Abnormal constitution was observed in all cells by G-band karyotyping. The culture cells were easily transplanted into the subcutis of nude mouse and produced the tumor resembling the original tumor.


Asunto(s)
Neoplasias Encefálicas/patología , Glioblastoma/patología , Anciano , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/ultraestructura , Línea Celular Tumoral , Proliferación Celular , Femenino , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/ultraestructura , Humanos , Cariotipificación , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Microscopía Electrónica de Transmisión , Trasplante de Neoplasias
9.
Hum Cell ; 18(1): 67-72, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16130902

RESUMEN

A cell line designated "HIBSPP" was established from a human malignant choroids plexus papilloma of 29-year-old Japanese woman. This line grew well without interruption for 3 years and was subcultivated over 70 times. The cells were spindle, oval, and polygonal in shape, and neoplastic and pleomorphic features, a jigsaw puzzle-like arrangement, multilayering and forming papillary structures without contact inhibition. The cells proliferated slowly, and the population doubling time was about 69 hours. The chromosome number showed a wide distribution of aneuploidy. The mode was in the hypotetraploid range, and many marker chromosomes were observed. The culture cells were easily transplanted into the subcutis of nude mice and produced the tumor resembling the original tumor.


Asunto(s)
Neoplasias del Plexo Coroideo/patología , Glioma/patología , Adulto , Aneuploidia , Animales , Antígenos de Neoplasias/análisis , Línea Celular Tumoral , Proliferación Celular , Neoplasias del Plexo Coroideo/genética , Neoplasias del Plexo Coroideo/metabolismo , Neoplasias del Plexo Coroideo/ultraestructura , Medios de Cultivo/química , Femenino , Glioma/genética , Glioma/metabolismo , Glioma/ultraestructura , Humanos , Cariotipificación , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Factores de Tiempo
10.
Hum Cell ; 17(3): 117-24, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15859156

RESUMEN

We placed in culture brain tumors from 45 cases (7 cases of astrocytoma, 2 from oligodendrogliomas, 2 glioblastomas, 2 ependymomas, 13 meningiomas, 6 pituitary adenomas, 5 neurinomas, a malignant lymphoma, a choroid plexus papilloma, and 6 metastatic tumors) and succeeded in making a primary culture from 33, and maintained 17 in vitro over a considerable period of time (greater than three months). In the early period of the primary cultures, the astrocytoma cells had cytoplasmic processes which contacted each other, the oligodendroglioma cells were small and spindle-shaped, the glioblastoma cells were neoplastic with pleopmorphic features and possessed cytoplasmic processes, the ependymoma cells formed a rosette-like cell arrangement, the meningioma cells were spindle- or round-shaped cells and characterized as forming psammoma bodies, the pituitary adenoma cells were round- or oval-shaped cells and produced growth hormone (GH), adenocorticoid tropic hormone (ACTH), prolactin, or other hypophyseal hormones, the choroid plexus papilloma cells were round-or polygonal and showed a papillary cell arrangement, the neurinoma cells were spindle- or fibrous-shaped cells, and the malignant lymphoma cells were round and formed cell aggregates floating in the culture medium.


Asunto(s)
Astrocitoma/patología , Neoplasias Encefálicas/patología , Adenoma/metabolismo , Adenoma/patología , Adolescente , Hormona Adrenocorticotrópica/biosíntesis , Adulto , Anciano , Astrocitoma/ultraestructura , Neoplasias Encefálicas/ultraestructura , Citoplasma/patología , Ependimoma/patología , Ependimoma/ultraestructura , Femenino , Glioblastoma/patología , Glioblastoma/ultraestructura , Hormona del Crecimiento/biosíntesis , Humanos , Linfoma/patología , Linfoma/ultraestructura , Masculino , Neoplasias Meníngeas/patología , Meningioma/patología , Microscopía , Persona de Mediana Edad , Neurilemoma/patología , Neurilemoma/ultraestructura , Oligodendroglioma/patología , Oligodendroglioma/ultraestructura , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Prolactina/biosíntesis , Células Tumorales Cultivadas
11.
Hum Cell ; 17(4): 211-7, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16035506

RESUMEN

We placed on culture the 13 cases of meningiomas, succeeded in making a primary culture of 10 cases and maintained 5 cases in vitro over considerable period of time (over three month), and one cell line derived from a malignant meningioma were established. In the early period of the primary culture, meningioma cells were spindle- or round-shaped cells. In the case of psammomatous type, the cultured cells were characterized as forming psammoma bodies. A cell line designated "HKBMM" was established from a human malignant meningioma occurred from frontal lobe. This line grew well without interruption for 5 years and was subcultivated over 120 times. The cells were spindle and fibrous in shape, and neoplastic and pleomorphic features, and multilayering without contact inhibition. The cells proliferated rapidly, and the population doubling time was about 29 hours. The chromosome number showed a wide distribution of aneuploidy. The mode was in the diploid range. The culture cells were easily transplanted into the subcutis of nude mice and produced the tumor resembling the original tumor.


Asunto(s)
Neoplasias Encefálicas/patología , Meningioma/patología , Animales , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Cromosomas Humanos , Femenino , Humanos , Cariotipificación , Meningioma/genética , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Trasplante de Neoplasias
12.
J Am Chem Soc ; 124(41): 12060-1, 2002 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-12371822

RESUMEN

Domino coupling of enones and enynes, which proceeds via the formation of three carbon-carbon bonds and the cleavage of one carbon-carbon bond, was developed using a Ni(0) and ZnCl2 system.

14.
J Org Chem ; 63(20): 7026-7029, 1998 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-11672328

RESUMEN

The [2 + 2 + 2] cycloaddition of diynes and enones occurred in the presence of both nickel and zinc together. This binary metal-mediated reaction had two interesting features: (1) a terminally unsubstituted diyne reacted with an enone to give an aromatic compound with the concomitant incorporation of two hydrogen atoms abstracted from an expected 1,3-diene product into another molecule of the starting enone and (2) a trimethylsilyl-substituted diyne reacted with an equimolar amount of enone to regioselectively afford a 1,3-diene, in which the trimethylsilyl group is adjacent to the carbonyl group.

15.
J Org Chem ; 62(8): 2544-2549, 1997 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-11671595

RESUMEN

2-Methyl-2-[(trimethylsilyl)methyl]-2,3,4,5,6,7-hexahydro-1H-2-benzazoninium iodide (9), 2-methyl-2-[(trimethylsilyl)methyl]-1,2,3,4,5,6-hexahydro-2-benzazocinium iodide (15), and 2-methyl-2-[(trimethylsilyl)methyl]-2,3,4,5-tetrahydro-1H-2-benzazepinium iodide (23) exist as mixtures of two stable conformational isomers (types A and B) in an aprotic solvent at room temperature. The corresponding conformational isomers of N-methylides 10A,B, 16A,B, and 24A,B were generated by fluoride ion-induced desilylation, and their rearrangement was investigated. Type A ylides gave [2,3] sigmatropic rearrangement products (isotoluenes) 11, 17, 18, and 27, while type B ylides gave Stevens rearrangement products 8, 20, and 29 via radical-cleavage and -recombination pathways.

16.
J Org Chem ; 61(23): 8248-8255, 1996 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11667812

RESUMEN

The nickel-catalyzed reaction of alpha,beta-enones 2 with alkynes 1, alkynyltins 6, and Me(3)SiCl was carried out by the successive construction of two carbon-carbon bonds to give enol silyl ethers 5, which were then hydrolyzed to conjugated enynes 7, with high regio- and stereoselectivities (isomeric purities: 92-98%).

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