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1.
BMC Neurol ; 22(1): 181, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35578314

RESUMEN

BACKGROUND: Bromine compounds are used in several drugs, including over-the-counter drugs. They sometimes cause intoxication known as bromism. Although the acute neurological symptoms and sequelae of bromism vary, few reports have mentioned acute encephalopathy. CASE PRESENTATION: We report two cases of bromisoval-induced bromism with status epilepticus. Presence of pseudohyperchloremia and history of over-the-counter medication use guided the diagnosis. In the acute phase, our patients showed bilateral medial thalamic lesions on magnetic resonance imaging. The imaging findings were similar to those of Wernicke's encephalopathy. Although these findings improved in the chronic phase, neuropsychiatric sequelae, such as confabulation and amnesia, occurred. CONCLUSION: Bromism can cause acute encephalopathy, and it is important to differentiate it from Wernicke-Korsakoff syndrome.


Asunto(s)
Bromisovalum , Síndrome de Korsakoff , Estado Epiléptico , Encefalopatía de Wernicke , Humanos , Síndrome de Korsakoff/complicaciones , Trastornos de la Memoria/etiología , Estado Epiléptico/complicaciones , Estado Epiléptico/diagnóstico , Encefalopatía de Wernicke/diagnóstico , Encefalopatía de Wernicke/etiología , Encefalopatía de Wernicke/patología
2.
Arch Orthop Trauma Surg ; 140(12): 2085-2089, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32940804

RESUMEN

Recently, catastrophic failure (i.e., dissociation between the metal femoral head and stem due to stem neck deformation) after total hip arthroplasty (THA) has been reported. Early detection of this complication is very important, because it is accompanied by an increased cobalt concentration in the body, which might influence systemic conditions such as heart failure and immune system diseases. However, early detection of stem neck deformation is considered as difficult. In most cases in the literatures, the diagnosis was made at the time of acute dissociation. We report a case of early detection of stem neck deformation with the 'Bowing-head sign' before acute dissociation. The patient is a 71-year old woman complained of a clicking sensation in the right hip during regular follow-up after THA with a 32-mm cobalt/chromium head with polyethylene insert for osteoarthritis performed 7 years previously. The plain radiograph showed that the angle between the metal femoral head and the axis of the stem neck was not perpendicular ('Bowing-head sign'). Dynamic evaluation under fluoroscopy showed movement of the stem neck in the metal femoral head with hip abduction and adduction. Laboratory data showed abnormal serum cobalt (6.3 µg/L, normal < 1 µg/L) and chromium (3.8 µg/L, normal < 5 µg/L) levels. Considering those radiographic findings, deformation of the stem neck due to trunnionosis was diagnosed, and elective revision surgery was performed without any complications. Plain radiographs after THA should be assessed with attention to this complication, 'Bowing-head sign' must not be overlooked.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Articulación de la Cadera/diagnóstico por imagen , Prótesis de Cadera , Falla de Prótesis , Anciano , Cromo/sangre , Aleaciones de Cromo , Cobalto/sangre , Diagnóstico Precoz , Intervención Médica Temprana , Femenino , Cabeza Femoral/cirugía , Humanos , Metales , Osteoartritis de la Cadera/cirugía , Polietileno , Radiografía , Reoperación/métodos
3.
J Am Chem Soc ; 141(7): 3083-3099, 2019 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-30698435

RESUMEN

The Illicium sesquiterpenes are a family of natural products containing over 100 highly oxidized and structurally complex members, many of which display interesting biological activities. This comprehensive account chronicles the evolution of a semisynthetic strategy toward these molecules from (+)-cedrol, seeking to emulate key aspects of their presumed biosynthesis. An initial route generated lower oxidation state analogs but failed in delivering a crucial hydroxy group in the final step. Insight gathered during these studies, however, ultimately led to a synthesis of the pseudoanisatinoids along with the allo-cedrane natural product 11- O-debenzoyltashironin. A second-generation strategy was then developed to access the more highly oxidized majucinoid compounds including jiadifenolide and majucin itself. Overall, one dozen natural products can be accessed from an abundant and inexpensive terpene feedstock. A multitude of general observations regarding site-selective C(sp3)-H bond functionalization reactions in complex polycyclic architectures are reported.


Asunto(s)
Sesquiterpenos/síntesis química , Biomimética , Oxidación-Reducción , Sesquiterpenos Policíclicos/química
4.
Chem Pharm Bull (Tokyo) ; 66(2): 178-183, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29386469

RESUMEN

Total syntheses of carbazomycins A and B were demonstrated using a ytterbium-catalyzed Diels-Alder reaction with (silyloxyvinyl)indole as a diene. The densely substituted benzene ring of the target compound was successfully constructed by functionalization of a hydrocarbazolone intermediate and subsequent aromatization using N-bromosuccinimide.


Asunto(s)
Carbazoles , Iterbio , Carbazoles/síntesis química , Catálisis , Reacción de Cicloadición , Iterbio/química
5.
J Am Chem Soc ; 138(51): 16616-16619, 2016 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-27966918

RESUMEN

Illicium sesquiterpenes have been the subject of numerous synthetic efforts due to their ornate and highly oxidized structures as well as significant biological activities. Herein we report the first chemical synthesis of (+)-pseudoanisatin from the abundant feedstock chemical cedrol (∼$50 USD/kg) in 12 steps using extensive site-selective C(sp3)-H bond functionalization. Significantly, this work represents a novel oxidative strategic template for future approaches to these natural products and their analogs.


Asunto(s)
Illicium/química , Lactonas/química , Lactonas/síntesis química , Sesquiterpenos/química , Sesquiterpenos/síntesis química , Compuestos de Espiro/química , Compuestos de Espiro/síntesis química , Técnicas de Química Sintética , Oxidación-Reducción , Estereoisomerismo
6.
J Org Chem ; 80(17): 8859-67, 2015 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-26247095

RESUMEN

The catalytic and enantioselective total synthesis of (-)-minovincine has been accomplished. The key highly substituted hydrocarbazole derivative was obtained by an asymmetric Diels-Alder reaction of siloxyvinylindole catalyzed by 0.5 mol % of a chiral holmium complex. The Diels-Alder adduct was converted to a tetracyclic intermediate in a one-pot procedure. No waste stereoisomers were produced throughout the entire total synthesis.

7.
ISME J ; 13(2): 455-467, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30287885

RESUMEN

We investigated the phylogenetic diversity, localisation and metabolism of an uncultured bacterial clade, Termite Group 2 (TG2), or ZB3, in the termite gut, which belongs to the candidate phylum 'Margulisbacteria'. We performed 16S rRNA amplicon sequencing analysis and detected TG2/ZB3 sequences in 40 out of 72 termite and cockroach species, which exclusively constituted a monophyletic cluster in the TG2/ZB3 clade. Fluorescence in situ hybridisation analysis in lower termites revealed that these bacteria are specifically attached to ectosymbiotic spirochetes of oxymonad gut protists. Draft genomes of four TG2/ZB3 phylotypes from a small number of bacterial cells were reconstructed, and functional genome analysis suggested that these bacteria hydrolyse and ferment cellulose/cellobiose to H2, CO2, acetate and ethanol. We also assembled a draft genome for a partner Treponema spirochete and found that it encoded genes for reductive acetogenesis from H2 and CO2. We hypothesise that the TG2/ZB3 bacteria we report here are commensal or mutualistic symbionts of the spirochetes, exploiting the spirochetes as H2 sinks. For these bacteria, we propose a novel genus, 'Candidatus Termititenax', which represents a hitherto uncharacterised class-level clade in 'Margulisbacteria'. Our findings add another layer, i.e., cellular association between bacteria, to the multi-layered symbiotic system in the termite gut.


Asunto(s)
Bacterias/genética , Isópteros/microbiología , Filogenia , Simbiosis , Animales , Bacterias/clasificación , Genoma , Hibridación Fluorescente in Situ , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Spirochaetales/genética
8.
Microbes Environ ; 33(1): 50-57, 2018 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-29415909

RESUMEN

Termite guts harbor diverse yet-uncultured bacteria, including a non-photosynthetic cyanobacterial group, the class "Melainabacteria". We herein reported the phylogenetic diversity of "Melainabacteria" in the guts of diverse termites and conducted a single-cell genome analysis of a melainabacterium obtained from the gut of the termite Termes propinquus. We performed amplicon sequencing of 16S rRNA genes from the guts of 60 termite and eight cockroach species, and detected melainabacterial sequences in 48 out of the 68 insect species, albeit with low abundances (0.02-1.90%). Most of the melainabacterial sequences obtained were assigned to the order "Gastranaerophilales" and appeared to form clusters unique to termites and cockroaches. A single-cell genome of a melainabacterium, designated phylotype Tpq-Mel-01, was obtained using a fluorescence-activated cell sorter and whole genome amplification. The genome shared basic features with other melainabacterial genomes previously reconstructed from the metagenomes of human and koala feces. The bacterium had a small genome (~1.6 Mb) and possessed fermentative pathways possibly using sugars and chitobiose as carbon and energy sources, while the pathways for photosynthesis and carbon fixation were not found. The genome contained genes for flagellar components and chemotaxis; therefore, the bacterium is likely motile. A fluorescence in situ hybridization analysis showed that the cells of Tpq-Mel-01 and/or its close relatives are short rods with the dimensions of 1.1±0.2 µm by 0.5±0.1 µm; for these bacteria, we propose the novel species, "Candidatus Gastranaerophilus termiticola". Our results provide fundamental information on "Melainabacteria" in the termite gut and expand our knowledge on this underrepresented, non-photosynthetic cyanobacterial group.


Asunto(s)
Cianobacterias/genética , Genoma Bacteriano , Isópteros/microbiología , Fotosíntesis , Filogenia , Animales , Cianobacterias/clasificación , Microbioma Gastrointestinal , Variación Genética , Hibridación Fluorescente in Situ , ARN Ribosómico 16S/genética , Análisis de la Célula Individual , Simbiosis
9.
Org Lett ; 15(20): 5314-7, 2013 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-24079531

RESUMEN

The catalytic and asymmetric cycloaddition between 3-[1-(silyloxy)vinyl]indoles and electron-deficient olefins gave substituted hydrocarbazoles in up to 99% yield and 94% ee. This reaction was catalyzed by a novel chiral holmium(III) complex. Alkylation of the cycloadduct gave a tricyclic compound with four continuous chiral centers, one of which was a quaternary carbon.


Asunto(s)
Carbazoles/síntesis química , Holmio/química , Indoles/química , Compuestos Organometálicos/química , Silanos/química , Alquenos/química , Carbazoles/química , Catálisis , Ciclización , Estructura Molecular , Estereoisomerismo
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