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1.
Angew Chem Int Ed Engl ; 63(28): e202407095, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38658318

RESUMEN

Chirality-driven self-sorting plays an essential role in controlling the biofunction of biosystems, such as the chiral double-helix structure of DNA from self-recognition by hydrogen bonding. However, achieving precise control over the chiral self-sorted structures and their functional properties for the bioinspired supramolecular systems still remains a challenge, not to mention realizing dynamically reversible regulation. Herein, we report an unprecedented saucer[4]arene-based charge transfer (CT) cocrystal system with dynamically reversible chiral self-sorting synergistically induced by chiral triangular macrocycle and organic vapors. It displays efficient chain length-selective vapochromism toward alkyl ketones due to precise modulation of optical properties by vapor-induced diverse structural transformations. Experimental and theoretical studies reveal that the unique vapochromic behavior is mainly attributed to the formation of homo- or heterochiral self-sorted assemblies with different alkyl ketone guests, which differ dramatically in solid-state superstructures and CT interactions, thus influencing their optical properties. This work highlights the essential role of chiral self-sorting in controlling the functional properties of synthetic supramolecular systems, and the rarely seen controllable chiral self-sorting at the solid-vapor interface deepens the understanding of efficient vapochromic sensors.

2.
Ocul Immunol Inflamm ; 31(8): 1720-1723, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35802352

RESUMEN

PURPOSE: To report a rare case of cystoid macular edema (CME) as a presentation of acute hydroxychloroquine-related retinal toxicity. OBSERVATIONS: A 37-year-old female patient visited our ophthalmology department in October 2019 complaining of bilateral blurred vision and metamorphopsia for 3 days. Best-corrected visual acuity (BCVA) was 6/6 in the right eye and 6/7.5 in the left eye under the Snellen E chart. Before presentation, she had taken hydroxychloroquine as a "reproduction-facilitating medication" prior to the in vitro fertilization (IVF) procedures with the daily dose of 200 mg for 1 week in March 2019 and 400 mg for 1 month in September 2019. She also took a combination of several herbal medicine including "Angelica sinensis" for 6 months in this period. On examination, typical signs of hydroxychloroquine maculopathy such as bilateral paracentral retinal pigment epithelium (RPE) change in blue autofluorescence and loss of the paracentral ellipsoid zone in optical coherence tomography ("flying saucer sign") were noted. CME was also found in fluorescein angiography. Her symptoms improved gradually after cessation of hydroxychloroquine and herb medicine without any further treatment. Resolution of bilateral CME was revealed at 16 weeks with final bilateral BCVA 6/6. CONCLUSIONS AND IMPORTANCE: Although rare, acute hydroxychloroquine maculopathy could occur in patients with concomitant usage of medications that could interfere with P450 enzymes system. Careful acquisition of drug history and serial ophthalmological examinations are advised in using hydroxychloroquine for disease management even for a short period of time.


Asunto(s)
Antirreumáticos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Degeneración Macular , Edema Macular , Enfermedades de la Retina , Humanos , Femenino , Adulto , Hidroxicloroquina/efectos adversos , Antirreumáticos/efectos adversos , Enfermedades de la Retina/inducido químicamente , Enfermedades de la Retina/diagnóstico , Edema Macular/inducido químicamente , Edema Macular/diagnóstico , Edema Macular/tratamiento farmacológico , Trastornos de la Visión/tratamiento farmacológico , Tomografía de Coherencia Óptica , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/tratamiento farmacológico , Angiografía con Fluoresceína
3.
Anat Histol Embryol ; 52(2): 127-134, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36562319

RESUMEN

To provide concise and brief important stereological application methods and techniques for estimating biological tissues. Stereology studies the quantity of biological tissue using little practice and the low price of counting and preparing tissue slices to obtain direct and accurate results. Since their establishment, the stereological techniques underwent much improvement, thus allowing more precise analysis of target structures using various approaches. Using stereological tools, advances in stereological techniques made the target tissues or organs represented by 2D instead of 3D dimensions. Process tools estimate volume, area and length. According to the exciting tissue and aims, the stereological tools perform differently. This review summarizes various stereological tools and techniques, providing brief information about the orientation method, slicer probe method, Delesse's principle, Cavalieri principle, disector, fractionator, nucleator, virtual cycloids and saucer, which are described in detail.


Asunto(s)
Recuento de Células , Técnicas In Vitro , Animales
4.
Zootaxa ; 4958(1): zootaxa.4958.1.7, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33903454

RESUMEN

The genus Cryphocricos Signoret, 1850 was recently determined in a molecular phylogeny to be distantly related to other taxa of the subfamily Cryphocricinae to the extent that it is now once again the sole member of the subfamily. This exclusively New World group of aquatic bugs lives in fast and usually turbulent current and respires by means of a plastron. Efforts to identify morphological features to distinguish among the species have largely fallen short, and some species have been established based on features that exhibit a high degree of intraspecific variation overlapping those of other species. Presented here is a review of the 13 described species with discussions of their features and photos of type specimens, and three new species from Venezuela and Colombia are described. Also presented is a diagnostic attribute unique to the enigmatic Cryphocricos barozzii Signoret, 1850.


Asunto(s)
Heterópteros , Filogenia , Distribución Animal , Animales , Heterópteros/anatomía & histología , Heterópteros/clasificación , Especificidad de la Especie
5.
Molecules ; 25(23)2020 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-33255853

RESUMEN

Breynia retusa (Dennst.) Alston (also known as Cup Saucer plant) is a food plant with wide applications in traditional medicine, particularly in Ayurveda. Extracts obtained with four solvents (dichloromethane, methanol, ethyl acetate and water), from three plant parts, (fruit, leaf and bark) were obtained. Extracts were tested for total phenolic, flavonoid content and antioxidant activities using a battery of assays including 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), total antioxidant capacity (TAC) (phosphomolybdenum) and metal chelating. Enzyme inhibitory effects were investigated using acetylcholinesterase (AChE), butyrylcholinesterase (BChE), tyrosinase, α-amylase and α-glucosidase as target enzymes. Results showed that the methanolic bark extract exhibited significant radical scavenging activity (DPPH: 202.09 ± 0.15; ABTS: 490.12 ± 0.18 mg Trolox equivalent (TE)/g), reducing potential (FRAP: 325.86 ± 4.36: CUPRAC: 661.82 ± 0.40 mg TE/g) and possessed the highest TAC (3.33 ± 0.13 mmol TE/g). The methanolic extracts were subjected to LC-DAD-MSn and NMR analysis. A two-column LC method was developed to separate constituents, allowing to identify and quantify forty-four and fifteen constituents in bark and fruits, respectively. Main compound in bark was epicatechin-3-O-sulphate and isolation of compound was performed to confirm its identity. Bark extract contained catechins, procyanidins, gallic acid derivatives and the sulfur containing spiroketal named breynins. Aerial parts mostly contained flavonoid glycosides. Considering the bioassays, the methanolic bark extract resulted a potent tyrosinase (152.79 ± 0.27 mg kojic acid equivalent/g), α-amylase (0.99 ± 0.01 mmol acarbose equivalent ACAE/g) and α-glucosidase (2.16 ± 0.01 mmol ACAE/g) inhibitor. In conclusion, methanol is able to extract the efficiently the phytoconstituents of B. retusa and the bark is the most valuable source of compounds.


Asunto(s)
Frutas/química , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Tracheophyta/química , Antioxidantes/química , Antioxidantes/farmacología , Cromatografía , Cromatografía Liquida , Minería de Datos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Fitoquímicos/química , Extractos Vegetales/farmacología
6.
Zootaxa ; 4860(3): zootaxa.4860.3.3, 2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-33055887

RESUMEN

The New World genus Limnocoris Stål includes 73 described species, of which 13 are distributed in North America. A new species, Limnocoris rodriguesi Reynoso n. sp., from Mexico is described and illustrated, bringing the total number of species distributed in the country to eight. An updated checklist of the Mexican fauna of Limnocoris is presented and includes new state records for six species: Limnocoris hintoni La Rivers, L. inornatus Montandon, L. insularis Champion, L. lutzi La Rivers, L. pygmaeus La Rivers, and L. signoreti Montandon. Additionally, distribution maps for each of the species of Limnocoris in Mexico are presented.


Asunto(s)
Heterópteros , Distribución Animal , Animales , México , Ríos
7.
J Am Mosq Control Assoc ; 36(2): 123-126, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33647131

RESUMEN

Plant saucers are ubiquitous, outdoor water-holding receptacles and are one of the most productive domestic mosquito habitats in the urban environment. Two kinds of commonly used plant saucers, clay and plastic, were manually treated with 3 residual insecticides, bifenthrin (Talstar® Professional), lambda-cyhalothrin (Lambda 9.7 CS), and tau-fluvalinate (Mavrik® Perimeter), at their maximum rates to assess their residual efficacy against Aedes albopictus larvae under semi-field and field conditions. Both clay and plastic saucers treated with bifenthrin and lambda-cyhalothrin provided weeks of control of 3rd instars of Ae. albopictus, whereas tau-fluvalinate provided only 1 day of control. Results from this study show that bifenthrin and lambda-cyhalothrin can provide good control of Ae. albopictus larvae for a considerable period of time and have great potential with regard to container mosquito management in the future.


Asunto(s)
Aedes , Insecticidas , Residuos de Plaguicidas , Animales , Larva
8.
Plant Cell Physiol ; 61(2): 308-317, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31626281

RESUMEN

Following exposure to water, mature Arabidopsis seeds are surrounded by a gelatinous capsule, termed mucilage. The mucilage consists of pectin-rich polysaccharides, which are produced in epidermal cells of the seed coat. Although pectin is a major component of plant cell walls, its biosynthesis and biological functions are not fully understood. Previously, we reported that a transmembrane RING E3 ubiquitin ligase, FLYING SAUCER 1 (FLY1) regulates the degree of pectin methyl esterification for mucilage capsule formation. The Arabidopsis thaliana genome has a single FLY1 homolog, FLY2. In this study, we show that the FLY2 protein functions in mucilage modification together with FLY1. FLY2 was expressed in seed coat epidermal cells during mucilage synthesis, but its expression level was much lower than that of FLY1. While fly2 showed no obvious difference in mucilage capsule formation from wild type, the fly1 fly2 double mutants showed more severe defects in mucilage than fly1 alone. FLY2-EYFP that was expressed under the control of the FLY1 promoter rescued fly1 mucilage, showing that FLY2 has the same molecular function as FLY1. FLY2-EYFP colocalized with marker proteins of Golgi apparatus (sialyltransferase-mRFP) and late endosome (mRFP-ARA7), indicating that as FLY1, FLY2 controls pectin modification by functioning in these endomembrane organelles. Furthermore, phylogenetic analysis suggests that FLY1 and FLY2 originated from a common ancestral gene by gene duplication prior to the emergence of Brassicaceae. Taken together, our findings suggest that FLY2 functions in the Golgi apparatus and/or the late endosome of seed coat epidermal cells in a manner similar to FLY1.


Asunto(s)
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Mucílago de Planta/genética , Mucílago de Planta/metabolismo , Semillas/metabolismo , Arabidopsis/genética , Pared Celular/metabolismo , Endosomas/metabolismo , Células Epidérmicas , Esterificación , Regulación de la Expresión Génica de las Plantas , Aparato de Golgi/metabolismo , Pectinas/metabolismo , Filogenia , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Semillas/genética , Ubiquitina-Proteína Ligasas/metabolismo
9.
Zootaxa ; 4615(2): zootaxa.4615.2.3, 2019 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-31716343

RESUMEN

The genus Ambrysus Stål is the most species rich genus of Naucoridae. Multiple species groups in the genus have been proposed, including the North American Ambrysus signoreti Stål complex. Four new species belonging to the A. signoreti complex are described and illustrated: three from Mexico (Ambrysus brailovskyi Reynoso Sites n. sp., A. henryi Reynoso Sites n. sp., A. schuhi Reynoso Sites n. sp.) and one from Mexico and Guatemala (A. sitesi Reynoso n. sp.), bringing the total number of described species of Ambrysus to 97.


Asunto(s)
Heterópteros , Distribución Animal , Animales , Guatemala , México
10.
Zootaxa ; 4629(4): zootaxa.4629.4.1, 2019 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-31712498

RESUMEN

The North American species of Limnocoris are revised and total 13 species after the present study. Four new species are described and illustrated: L. chaetocarinatus n. sp. from Costa Rica, Panama, and Colombia; L. major n. sp. and L. nanus n. sp. from Costa Rica and Panama; and L. zacki n. sp. from Mexico and Guatemala. Further, supplemental descriptions are provided for the previously described species. The following synonymies are proposed, with junior synonyms in brackets: L. insularis Champion [L. alcorni La Rivers n. syn.], L. pygmaeus La Rivers [L. solenoides La Rivers n. syn.], and L. signoreti Montandon [L. brailovskyi La Rivers n. syn., L. laucki La Rivers n. syn., L. stangei La Rivers n. syn.]. A lectotype is designated for L. signoreti. Limnocoris profundus (Say) is considered a nomen dubium because no type specimens have been found and the original description is insufficient to establish its identity. An illustrated taxonomic key, distribution maps, and a discussion of the characters (putative synapomorphies) not previously mentioned in the literature also are presented.


Asunto(s)
Heterópteros , Distribución Animal , Animales , América del Norte
11.
Mil Med ; 184(9-10): 561-564, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31197353

RESUMEN

Lepromatous leprosy represents a cutaneous infection by the bacterium Mycobacterium leprae. Once considered a common, fatal disease, leprosy has become increasingly rare with modern, inexpensive antibiotics. Most healthcare workers will never encounter a case of leprosy due to the low prevalence of the disease. However, military physicians, through deployments and contact with foreign-born servicemembers, are one of the first lines of defense against this disease. With an unknown method of transmission and an insidiously slow replication, it can take years for the disease to fully manifest. There are multiple cutaneous manifestations associated with the infection that can mimic other infectious etiologies, stalling appropriate diagnosis and treatment. To determine which treatment course is recommended requires evaluation of disease dissemination and the level of host immune response. As the incidence of reported leprosy cases continues to decline, disease education on diagnosis and treatment is imperative to enhance early detection and intervention. Understanding the populations at risk for leprosy and its insidious presentation will aid the practitioner in minimizing disease burden for both U.S. servicemembers and our foreign partners.


Asunto(s)
Lepra/diagnóstico , Personal Militar , Dapsona/uso terapéutico , Diagnóstico Tardío , Exantema/etiología , Humanos , Leprostáticos/uso terapéutico , Lepra/tratamiento farmacológico , Lepra/patología , Masculino , Micronesia , Mycobacterium leprae/efectos de los fármacos , Mycobacterium leprae/patogenicidad , Adulto Joven
12.
Mikrochim Acta ; 186(4): 213, 2019 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-30830305

RESUMEN

An enzyme-metal organic framework (MOF) composite with saucer-like structure was prepared via one-pot synthesis from ficin (a cysteine proteolytic enzyme with POx activity), zinc(II) ions and 2-methylimidazole. The composites exhibit a 2.5-fold higher catalytic activity and stronger affinity for substrates compared to free ficin. This was exploited to design a colorimetric assay for the determination of glucose. The addition of glucose oxidase causes the formation of H2O2 which is catalytically oxidized by ficin to form a blue coloration that can be measured at 652 nm. The assay has a 0.12 µM detection limit and excellent selectivity. It was successfully applied to the determination of glucose in diluted serum samples. Graphical abstract Schematic presentation of the synthesis process and the enhanced peroxidase activity of ficin@MOF composites. Ficin was immobilized in a new saucer-like shape of Ficin@MOF composites, which showed higher peroxidase activity than free ficin. Scheme and graphical abstract contains poor quality of text.We have attach a new picture with 600 dpi as scheme and graphical abstract.


Asunto(s)
Glucemia/análisis , Ficaína/química , Imidazoles/química , Estructuras Metalorgánicas/química , Peroxidasas/metabolismo , Zinc/química , Técnicas Biosensibles/métodos , Color , Colorimetría/métodos , Colorantes/química , Peróxido de Hidrógeno/análisis , Cinética , Nanocompuestos/química , Tamaño de la Partícula , Propiedades de Superficie
13.
Zootaxa ; 4491(1): 1-64, 2018 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-30313725

RESUMEN

The Ambrysus pudicus Stål species complex is revised, its species diagnosed, and an illustrated key is presented. The complex includes A. abortus La Rivers, A. amargosus La Rivers, A. funebris La Rivers, A. hungerfordi Usinger, A. parviceps Montandon, A. pudicus Stål, and A. relictus Polhemus Polhemus. A new species, A. chinanteco, belonging to this complex is described from southern Mexico. The subspecies A. hungerfordi angularis La Rivers, A. h. spicatus La Rivers, and A. h. triunfo La Rivers are herein elevated to full species level and considered members of this species complex. The subspecies A. pudicus barberi Usinger is synonymized with the nominate subspecies. Based on specific combinations of morphological features, two subcomplexes of species are recognized within the complex. The species A. funebris is transferred from the subgenus Acyttarus La Rivers to the subgenus Ambrysus Stål. In order to fix the identity of three species in the complex, neotypes for A. amargosus and A. spicatus and a lectotype for A. pudicus are designated here. The species in the A. pudicus complex are distributed in North America from the southwestern and southern United States to northern Costa Rica. New country records from Central America are presented for A. parviceps and A. pudicus. New state records from Mexico are presented for A. abortus, A. angularis, A. hungerfordi, A. parviceps, A. pudicus, and A. spicatus.


Asunto(s)
Distribución Animal , Heterópteros , Estructuras Animales , Animales , Tamaño Corporal , América Central , Costa Rica , México , América del Norte , Tamaño de los Órganos
14.
Zootaxa ; 4442(3): 351-377, 2018 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-30313969

RESUMEN

The Ambrysus pulchellus Montandon species complex is revised and includes A. buenoi Usinger, A. californicus Montandon, A. pulchellus Montandon, and A. vanduzeei Usinger. The unifying features among species in this complex are related to the morphology of the male phallosoma and the medial lobes of abdominal tergum VIII. The species in this complex are diagnosed and a key for identification is presented. The subspecies A. pulchellus nitidulus Montandon and A. pulchellus pallidulus Montandon are proposed as junior synonyms of A. pulchellus Montandon. Ambrysus pulchellus is newly recorded from Honduras, Nicaragua, and Panama in Central America. This species has the widest distribution in the subgenus Ambrysus Stål and includes parts of the Nearctic and Neotropical biogeographic realms. Ambrysus buenoi is distributed in Mexico and the United States, whereas A. californicus is endemic to the coastal ranges of California in the United States and A. vanduzeei to the Baja California Peninsula in Mexico.


Asunto(s)
Distribución Animal , Heterópteros , Animales , California , América Central , Honduras , Masculino , México , Nicaragua , Panamá
15.
Zootaxa ; 4221(3): zootaxa.4221.3.8, 2017 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-28187671

RESUMEN

Gobiesox lanceolatus is described from a single specimen collected from 300 meters depth in the Los Frailes submarine canyon in the southwestern Gulf of California. The "Canyon Clingfish" is unique within Gobiesox in having a lanceolate caudal fin, with the central rays longer than those above and below them. It is also distinguished by 14 dorsal-fin rays (first tiny and unsegmented), 11 anal-fin rays, 28 pectoral-fin rays, anus slightly closer to anal-fin origin than to posterior margin of pelvic disc, and dorsal-fin origin in front of vertical from anus. It is most similar to Gobiesox eugrammus, known from Isla Guadelupe, the coast of outer Baja California and southern California. This is the deepest record for a species of Gobiesox and only four other species of clingfishes are known from greater depths.


Asunto(s)
Perciformes , Distribución Animal , Animales , California , México
16.
Arch Soc Esp Oftalmol ; 91(9): 450-2, 2016 Sep.
Artículo en Inglés, Español | MEDLINE | ID: mdl-27005921

RESUMEN

CLINICAL CASE: The case is presented of a 56 year-old patient diagnosed with rhegmatogenous retinal detachment and on treatment with hydroxychloroquine (HCQ). A Spectral Domain-Optical Coherence Tomography (SD-OCT) was performed that showed changes in the outer retina in the eye with macular detachment, as well as the «flying saucer¼ sign in the other eye. After a complete retinopexy the «flying saucer¼ sign was still present. DISCUSSION: SD-OCT could be used as a test in order to reveal HCQ toxicity in the event of retinal detachment. In this case, this technique shows abnormalities such as a hyper-reflective line in the outer retina layers.


Asunto(s)
Enfermedades Hereditarias del Ojo/tratamiento farmacológico , Hidroxicloroquina/efectos adversos , Mácula Lútea/diagnóstico por imagen , Desprendimiento de Retina/tratamiento farmacológico , Perforaciones de la Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica , Exudados y Transudados , Enfermedades Hereditarias del Ojo/cirugía , Femenino , Humanos , Fotocoagulación , Mácula Lútea/efectos de los fármacos , Persona de Mediana Edad , Imagen Óptica , Desprendimiento de Retina/cirugía , Perforaciones de la Retina/cirugía , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Vitrectomía
17.
Arch Soc Esp Oftalmol ; 90(7): 338-40, 2015 Jul.
Artículo en Español | MEDLINE | ID: mdl-25443193

RESUMEN

CASE REPORTS: Two asymptomatic women treated with hydroxychloroquine 200mg every day for 8 and 16 years developed retinal toxicity. DISCUSSION: Patient 1 was found to have a normal fundus and autofluorescence examination. Patient 2 was found to have a completely normal fundus examination. Fluorescein angiography shows parafoveal hyperfluorescence, and autofluorescence shows a minimal decrease in signal in the same region. In both patients the SD-OCT shows disruption of the ellipsoid zone in parafoveal region («flying saucer¼ sign). SD-OCT findings in the retina can identify hydroxychloroquine retinopathy in asymptomatic patients.


Asunto(s)
Antirreumáticos/efectos adversos , Fóvea Central/diagnóstico por imagen , Hidroxicloroquina/efectos adversos , Enfermedades de la Retina/inducido químicamente , Enfermedades de la Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica , Adolescente , Artritis Reumatoide/tratamiento farmacológico , Femenino , Angiografía con Fluoresceína , Fondo de Ojo , Humanos , Lupus Eritematoso Sistémico/tratamiento farmacológico
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