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1.
A A Pract ; 14(11): e01315, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32985852

RESUMEN

Guillain-Barre syndrome (GBS) is a peripheral demyelinating neuromuscular disorder occasionally associated with pharmacologically refractory neuropathic pain. We present a case of acute neuropathic pain in a 22-year-old man with GBS managed with percutaneous peripheral nerve stimulation (PNS). Following implantation of leads in the bilateral sciatic, femoral, and brachial plexus nerve distribution, the patient experienced significant pain reduction in both the upper and lower extremities. Analgesic and anxiolytic medications were reduced by 33% on the first day and by 78% on day 21. PNS is a minimally invasive, nonpharmacologic modality for treating acute neuropathic pain in GBS patients.


Asunto(s)
Plexo Braquial , Síndrome de Guillain-Barré , Neuralgia , Estimulación Eléctrica Transcutánea del Nervio , Adulto , Síndrome de Guillain-Barré/complicaciones , Síndrome de Guillain-Barré/terapia , Humanos , Masculino , Neuralgia/etiología , Neuralgia/terapia , Adulto Joven
2.
Sci Rep ; 8(1): 14952, 2018 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-30297734

RESUMEN

We have investigated current-current correlations in a cross-shaped conductor made of graphene. The mean free path of charge carriers is on the order of the ribbon width which leads to a hybrid conductor where there is diffusive transport in the device arms while the central connection region displays near ballistic transport. Our data on auto and cross correlations deviate from the predictions of Landauer-Büttiker theory, and agreement can be obtained only by taking into account contributions from non-thermal electron distributions at the inlets to the semiballistic center, in which the partition noise becomes strongly modified. The experimental results display distinct Hanbury - Brown and Twiss (HBT) exchange correlations, the strength of which is boosted by the non-equilibrium occupation-number fluctuations internal to this hybrid conductor. Our work demonstrates that variation in electron coherence along atomically-thin, two-dimensional conductors has significant implications on their noise and cross correlation properties.

3.
J Acoust Soc Am ; 143(2): 878, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29495725

RESUMEN

A method of localizing unknown acoustic sources using data derived replicas from ships of opportunity has been reported previously by Verlinden, Sarkar, Hodgkiss, Kuperman, and Sabra [J. Acoust. Soc. Am, 138(1), EL54-EL59 (2015)]. The method is similar to traditional matched field processing, but differs in that data-derived measured replicas are used in place of modeled replicas and, in order to account for differing source spectra between library and target vessels, cross-correlation functions are compared instead of comparing acoustic signals directly. The method is capable of localizing sources in positions where data derived replicas are available, such as locations previously transited by ships tracked using the Automatic Identification System, but is limited by the sparsity of ships of opportunity. This paper presents an extension of this localization method to regions where data derived replicas are not available by extrapolating the measured cross-correlation function replicas onto a larger search grid using waveguide invariant theory. This new augmentation provides a method for continuous tracking.

4.
J Acoust Soc Am ; 141(2): EL102, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28253685

RESUMEN

The waveguide invariant (WGI) is a property that can be used to localize acoustic radiators and extract information about the environment. Here the WGI is determined using ships as sources of opportunity, tracked using the Automatic Identification System (AIS). The relationship between range, acoustic intensity, and frequency for a ship in a known position is used to determine the WGI parameter ß. These ß values are interpolated and a map of ß is generated. The method is demonstrated using data collected in a field experiment on a single hydrophone in a shallow water environment off the coast of Southern California.

5.
J Acoust Soc Am ; 140(3): EL247, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27914378

RESUMEN

A deep-water experiment in the Pacific made in situ measurements of the volume attenuation coefficients of sea water in the mid-frequency range. The frequency, temperature, salinity, pH, and pressure dependent seawater attenuation coefficients were determined using a vertical line array that received and identified over 2000 unique paths from 1200 mid-frequency 3-9 kHz LFM source transmissions at a convergence zone range and depth up to 400 m. The results show no change in attenuation coefficients in this band compared to estimates from 30-year-old models previously determined from a combination of long-range ocean acoustic and laboratory experiments. The inversion also explores the feasibility of ocean acoustic attenuation tomography to further separate the depth-dependent chemical components responsible for the total attenuation loss through by isolating a group of deep-water refracting acoustic paths.

6.
Nature ; 539(7629): 407-410, 2016 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-27786173

RESUMEN

Energy dissipation is a fundamental process governing the dynamics of physical, chemical and biological systems. It is also one of the main characteristics that distinguish quantum from classical phenomena. In particular, in condensed matter physics, scattering mechanisms, loss of quantum information or breakdown of topological protection are deeply rooted in the intricate details of how and where the dissipation occurs. Yet the microscopic behaviour of a system is usually not formulated in terms of dissipation because energy dissipation is not a readily measurable quantity on the micrometre scale. Although nanoscale thermometry has gained much recent interest, existing thermal imaging methods are not sensitive enough for the study of quantum systems and are also unsuitable for the low-temperature operation that is required. Here we report a nano-thermometer based on a superconducting quantum interference device with a diameter of less than 50 nanometres that resides at the apex of a sharp pipette: it provides scanning cryogenic thermal sensing that is four orders of magnitude more sensitive than previous devices-below 1 µK Hz-1/2. This non-contact, non-invasive thermometry allows thermal imaging of very low intensity, nanoscale energy dissipation down to the fundamental Landauer limit of 40 femtowatts for continuous readout of a single qubit at one gigahertz at 4.2 kelvin. These advances enable the observation of changes in dissipation due to single-electron charging of individual quantum dots in carbon nanotubes. They also reveal a dissipation mechanism attributable to resonant localized states in graphene encapsulated within hexagonal boron nitride, opening the door to direct thermal imaging of nanoscale dissipation processes in quantum matter.

7.
Analyst ; 141(8): 2553-67, 2016 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-27027476

RESUMEN

In high throughput cell culture, the paradigm is now shifting from 2D to 3D systems. However, in 3D cell culture systems, it is important that the cells form spheroids with robust cell-cell interactions. We fabricated poly(N-isopropylacrylamide-co-gelatin) cryogel scaffolds for cell culture and inserted them into open-ended 96-well plates that formed a drainage and leakage protected, easy to handle high throughput platform. This platform was used to screen for the optimal concentration of poly(N-isopropylacrylamide) (pNIPAAm) as an external aid to the formation of cellular spheroids. It was found that hepatic cells (Hep G2) seeded in the presence of 0.03% pNIPAAm formed better hepatic spheroids in terms of morphology (as assessed by microscopic analysis and formation of bile canaliculi-like structures) and functionality by day 5 of culture. An increase of 44.22%, 15.75%, 36.44%, 32.05% and 27.02% was observed in glucose consumption (1.925 mM per day per 10(4) cells), albumin synthesis (164.18 ng per day per 10(4) cells), CYP1A1 (304.92 pg per min per 10(4) cells), CYP2A6 (441.23 nM per min per 10(4) cells) and phase II metabolic activity (386.18 nM per min(-1) per 10(4) cells), respectively, upon using 0.03% pNIPAAm, as compared to the 3D control. The platform was tested with other cells such as breast and lung cancer cells and found to be compatible. The cell spheroids were subjected to drug toxicity screening in cryogel based open-ended platforms. It was observed that the spheroids were more resistant to anticancer drugs, as compared to 2D and 3D controls, with approximately 11%-67% increase in the IC50 values of tamoxifen and paclitaxel. The platform also showed dose dependent and reproducible responses to drugs.


Asunto(s)
Resinas Acrílicas/farmacología , Antineoplásicos/farmacología , Técnicas de Cultivo de Célula/métodos , Criogeles/farmacología , Gelatina/farmacología , Ensayos Analíticos de Alto Rendimiento/métodos , Polímeros/farmacología , Esferoides Celulares/citología , Temperatura , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Esferoides Celulares/efectos de los fármacos
8.
Cell Death Dis ; 6: e1860, 2015 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-26313911

RESUMEN

α-Solanine is a glycoalkaloid found in species of the nightshade family including potato. It was primarily reported to have toxic effects in humans. However, there is a growing body of literature demonstrating in vitro and in vivo anticancer activity of α-solanine. Most of these studies have shown activation of apoptosis as the underlying mechanism in antitumor activity of α-solanine. In this study, we report α-solanine as a potential inducer of autophagy, which may act synergistically or in parallel with apoptosis to exert its cytotoxic effect. Induction of autophagy was demonstrated by several assays including electron microscopy, immunoblotting of autophagy markers and immunofluorescence for LC3 (microtubule-associated protein 1 (MAP1) light chain-3) puncta. α-Solanine-induced autophagic flux was demonstrated by additionally enhanced--turnover of LC3-II and--accumulation of LC3-specific puncta after co-incubation of cells with either of the autophagolysosome inhibitors--chloroquine and--bafilomycin A1. We also demonstrated α-solanine-induced oxidative damage in regulating autophagy where pre-incubation of cells with reactive oxygen species (ROS) scavenger resulted in suppression of CM-H2DCFDA (5 (and 6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate acetyl ester) fluorescence as well as decrease in LC3-II turnover. α-Solanine treatment caused an increase in the expression of endoplasmic reticulum (ER) stress proteins (BiP, activating transcription factor 6 (ATF6), X-box-binding protein 1, PERK, inositol-requiring transmembrane kinase/endonuclease 1, ATF4 and CCAAT-enhancer-binding protein (C/EBP)-homologous protein) suggesting activation of unfolded protein response pathway. Moreover, we found downregulation of phosphorylated Akt (Thr308 and Ser473), mammalian target of rapamycin (mTOR; Ser2448 and Ser2481) and 4E-BP1 (Thr37/46) by α-solanine implying suppression of the Akt/mTOR pathway. Collectively, our results signify that α-solanine induces autophagy to exert anti-proliferative activity by triggering ER stress and inhibiting Akt/mTOR signaling pathway.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Estrés del Retículo Endoplásmico/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Especies Reactivas de Oxígeno/agonistas , Solanina/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Factor de Transcripción Activador 4/genética , Factor de Transcripción Activador 4/metabolismo , Factor de Transcripción Activador 6/genética , Factor de Transcripción Activador 6/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Apoptosis/efectos de los fármacos , Familia de las Proteínas 8 Relacionadas con la Autofagia , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Línea Celular Tumoral , Cloroquina/farmacología , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Humanos , Macrólidos/farmacología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción del Factor Regulador X , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Respuesta de Proteína Desplegada/efectos de los fármacos , eIF-2 Quinasa/genética , eIF-2 Quinasa/metabolismo
9.
J Acoust Soc Am ; 138(1): EL54-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26233061

RESUMEN

The feasibility of using data derived replicas from ships of opportunity for implementing matched field processing is demonstrated. The Automatic Identification System (AIS) is used to provide the library coordinates for the replica library and a correlation based processing procedure is used to overcome the impediment that the replica library is constructed from sources with different spectra and will further be used to locate another source with its own unique spectral structure. The method is illustrated with simulation and then verified using acoustic data from a 2009 experiment for which AIS information was retrieved from the United States Coast Guard Navigation Center Nationwide AIS database.

10.
Persoonia ; 34: 167-266, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26240451

RESUMEN

Novel species of fungi described in the present study include the following from Malaysia: Castanediella eucalypti from Eucalyptus pellita, Codinaea acacia from Acacia mangium, Emarcea eucalyptigena from Eucalyptus brassiana, Myrtapenidiella eucalyptorum from Eucalyptus pellita, Pilidiella eucalyptigena from Eucalyptus brassiana and Strelitziana malaysiana from Acacia mangium. Furthermore, Stachybotrys sansevieriicola is described from Sansevieria ehrenbergii (Tanzania), Phacidium grevilleae from Grevillea robusta (Uganda), Graphium jumulu from Adansonia gregorii and Ophiostoma eucalyptigena from Eucalyptus marginata (Australia), Pleurophoma ossicola from bone and Plectosphaerella populi from Populus nigra (Germany), Colletotrichum neosansevieriae from Sansevieria trifasciata, Elsinoë othonnae from Othonna quinquedentata and Zeloasperisporium cliviae (Zeloasperisporiaceae fam. nov.) from Clivia sp. (South Africa), Neodevriesia pakbiae, Phaeophleospora hymenocallidis and Phaeophleospora hymenocallidicola on leaves of a fern (Thailand), Melanconium elaeidicola from Elaeis guineensis (Indonesia), Hormonema viticola from Vitis vinifera (Canary Islands), Chlorophyllum pseudoglobossum from a grassland (India), Triadelphia disseminata from an immunocompromised patient (Saudi Arabia), Colletotrichum abscissum from Citrus (Brazil), Polyschema sclerotigenum and Phialemonium limoniforme from human patients (USA), Cadophora vitícola from Vitis vinifera (Spain), Entoloma flavovelutinum and Bolbitius aurantiorugosus from soil (Vietnam), Rhizopogon granuloflavus from soil (Cape Verde Islands), Tulasnella eremophila from Euphorbia officinarum subsp. echinus (Morocco), Verrucostoma martinicensis from Danaea elliptica (French West Indies), Metschnikowia colchici from Colchicum autumnale (Bulgaria), Thelebolus microcarpus from soil (Argentina) and Ceratocystis adelpha from Theobroma cacao (Ecuador). Myrmecridium iridis (Myrmecridiales ord. nov., Myrmecridiaceae fam. nov.) is also described from Iris sp. (The Netherlands). Novel genera include (Ascomycetes): Budhanggurabania from Cynodon dactylon (Australia), Soloacrosporiella, Xenocamarosporium, Neostrelitziana and Castanediella from Acacia mangium and Sabahriopsis from Eucalyptus brassiana (Malaysia), Readerielliopsis from basidiomata of Fuscoporia wahlbergii (French Guyana), Neoplatysporoides from Aloe ferox (Tanzania), Wojnowiciella, Chrysofolia and Neoeriomycopsis from Eucalyptus (Colombia), Neophaeomoniella from Eucalyptus globulus (USA), Pseudophaeomoniella from Olea europaea (Italy), Paraphaeomoniella from Encephalartos altensteinii, Aequabiliella, Celerioriella and Minutiella from Prunus (South Africa). Tephrocybella (Basidiomycetes) represents a novel genus from wood (Italy). Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

11.
Early Child Dev Care ; 185(2): 291-316, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25632172

RESUMEN

In the first longitudinal, population-based study of full-day kindergarten (FDK) outcomes beyond primary school in Canada, we used linked administrative data to follow 15 kindergarten cohorts (n ranging from 112 to 736) up to grade 9. Provincial assessments conducted in grades 3, 7, and 8 and course marks and credits earned in grade 9 were compared between FDK and half-day kindergarten (HDK) students in both targeted and universal FDK programmes. Propensity score matched cohort and stepped-wedge designs allowed for stronger causal inferences than previous research on FDK. We found limited long-term benefits of FDK, specific to the type of programme, outcomes examined, and subpopulations. FDK programmes targeted at low-income areas showed long-term improvements in numeracy for lower income girls. Our results suggest that expectations for wide-ranging long-term academic benefits of FDK are unwarranted.

12.
Mol Oral Microbiol ; 29(5): 219-32, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24890414

RESUMEN

Treponema denticola is an oral spirochete and periopathogen that transitions from low abundance in healthy subgingival crevices to high abundance in periodontal pockets. The T. denticola response regulator AtcR harbors the relatively rare, LytTR DNA-binding domain. LytTR domain containing response regulators control critical transcriptional responses required for environmental adaptation. Using a multi-step bioinformatics approach, 26 strong lytTR recognition motifs were identified in the genome of T. denticola strain 35405. Electrophoretic mobility shift assays demonstrated that AtcR binds to these recognition motifs. High specificity-high affinity complexes formed with phosphorylated AtcR. The LytTR recognition sequences were found to exist in three distinct promoter architectures designated as LytTR1, LytTR2 and LytTR3 promoters. LytTR1 and LytTR2 promoters harbor σ(54) binding sites. The functional diversity of the proteins encoded by the putative AtcR regulon suggests that AtcR sits at the top of a regulatory cascade that plays a central role in facilitating T. denticola's ability to adapt to changing environmental conditions and thrive in periodontal pockets.


Asunto(s)
Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica/genética , Enfermedades Periodontales/microbiología , Regulón/genética , Factores de Transcripción/genética , Treponema denticola/genética , Adaptación Fisiológica/genética , Técnicas Bacteriológicas , Biología Computacional , Progresión de la Enfermedad , Ensayo de Cambio de Movilidad Electroforética , Genoma Bacteriano/genética , Humanos , Motivos de Nucleótidos/genética , Regiones Promotoras Genéticas/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Análisis de Secuencia de ADN , Factor sigma/genética , Transcripción Genética/genética
13.
Virusdisease ; 25(3): 408-11, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25674614

RESUMEN

The present study was undertaken to investigate the possible involvement of cattle in the epidemiology of peste des petits ruminants (PPR) as subclinical carriers. Cattle were exposed experimentally to PPR virus (PPRV) infection or placed in contact with PPR infected goats. Clinical samples including heparinized/EDTA blood, plasma, peripheral blood monocyte cells (PBMCs) and clotted blood (for serum) were collected periodically from 21 days post infection (dpi) to 397 dpi (21, 45, 50, 57, 65, 95, 111, 119, 148, 190, 203 and 397 dpi) and tested for PPRV antigen, nucleic acid and antibody. Exposed cattle seroconverted and maintained PPRV specific haemagglutinin antibodies and detectable PPRV antigen/nucleic acid in blood, plasma and PBMCs from 21 to 397 dpi. PPRV was recovered from blood and PBMC collected from experimental animals at 21 dpi, initially in B95a cells and then adapted to Vero cells. The study indicated that PPRV can infect cattle subclinically and PPRV antigen/nucleic acid persist in cattle for at least 397 days.

14.
Carbohydr Polym ; 89(4): 1159-65, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24750927

RESUMEN

A simple one-step rapid synthetic route is described for the preparation of silver nanoparticles by reduction of silver nitrate (AgNO3) using aqueous dextran solution which acts as both reducing and capping agent. The formation of silver nanoparticles is assured by characterization with UV-vis spectroscopy, atomic force microscopy (AFM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The absorbance of the silver nanoparticles is observed at 423 nm. The AFM image clearly shows the surface morphology of the well-dispersed silver nanoparticles with size range of 10-60 nm. TEM images show that the nanoparticles are spherical in shape with ∼5-10 nm dimensions. The crystallinity of Ag nanoparticles is assured by XRD analysis. The antimicrobial activity of as synthesized silver nanoparticles is tested against the bacteria, Bacillus subtilis, Bacillus cereus, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The bacterial growth is inhibited by gradual reduction of the concentration of the silver nanoparticles.


Asunto(s)
Antiinfecciosos , Bacterias/crecimiento & desarrollo , Nanopartículas del Metal/química , Plata , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Nanopartículas del Metal/ultraestructura , Tamaño de la Partícula , Plata/química , Plata/farmacología , Nitrato de Plata/química
15.
J Orthop Surg (Hong Kong) ; 19(3): 367-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22184173

RESUMEN

We report a rare case of concurrent palmar lunate dislocation of the left wrist combined with a posterior dislocation of the left elbow joint in a 40-year-old man. He sustained both injuries after falling onto his outstretched left hand. The elbow was reduced by the closed method. The wrist was treated with open reduction with carpal tunnel decompression and fixation with a Kirschner wire through the volar approach. Both the scapholunate and radioscaphocapitate ligaments were also repaired. At month 3, the patient had no pain in his elbow and minimal pain in his wrist on heavy lifting and had resumed his work as a porter.


Asunto(s)
Articulación del Codo/lesiones , Fijación Interna de Fracturas , Ligamentos Articulares/cirugía , Traumatismos de la Muñeca/cirugía , Accidentes por Caídas , Adulto , Hilos Ortopédicos , Descompresión Quirúrgica , Articulación del Codo/diagnóstico por imagen , Fijación Interna de Fracturas/métodos , Humanos , Luxaciones Articulares , Masculino , Radiografía , Traumatismos de la Muñeca/diagnóstico por imagen , Articulación de la Muñeca/diagnóstico por imagen
16.
J Dent Res ; 90(10): 1155-63, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21447698

RESUMEN

In the healthy subgingiva, oral treponemes account for a small percentage of the total bacteria. However, in diseased periodontal pockets, treponemes thrive and become a dominant component of the bacterial population. Oral treponemes are uniquely adept at capitalizing on the environmental conditions that develop with periodontal disease. The molecular basis of adaptive responses of oral treponemes is just beginning to be investigated and defined. The completion of several treponeme genome sequences and the characterization of global regulatory systems provide an important starting point in the analysis of signaling and adaptive responses. In this review, we discuss existing literature focused on the genetic regulatory mechanisms of Treponema denticola and present an overview of the possible roles of regulatory proteins identified through genome analyses. This information provides insight into the possible molecular mechanisms utilized by oral spirochetes to survive in the periodontal pocket and transition from a minor to a dominant organism.


Asunto(s)
Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Bolsa Periodontal/microbiología , Transducción de Señal/genética , Treponema denticola/genética , Adaptación Fisiológica , Animales , Secuencia de Bases , GMP Cíclico/análogos & derivados , GMP Cíclico/fisiología , ARN Polimerasas Dirigidas por ADN/genética , Histidina Quinasa , Humanos , Proteínas Quinasas/genética , Factor sigma/genética , Treponema denticola/fisiología
17.
Mol Oral Microbiol ; 25(4): 241-51, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20618698

RESUMEN

Treponema denticola levels in the gingival crevice become elevated as periodontal disease develops. Oral treponemes may account for as much as 40% of the total bacterial population in the periodontal pocket. The stimuli that trigger enhanced growth of T. denticola, and the mechanisms associated with the transmission of these signals, remain to be defined. We hypothesize that the T. denticola open reading frames tde1970 (histidine kinase) and tde1969 (response regulator) constitute a functional two-component regulatory system that regulates, at least in part, responses to the changing environmental conditions associated with the development of periodontal disease. The results presented demonstrate that tde1970 and tde1969 are conserved, universal among T. denticola isolates and transcribed as part of a seven-gene operon in a growth-phase-dependent manner. tde1970 undergoes autophosphorylation and transfers phosphate to tde1969. Henceforth, the proteins encoded by these open reading frames are designated as Hpk2 and Rrp2 respectively. Hpk2 autophosphorylation kinetics were influenced by environmental conditions and by the presence or absence of a PAS domain. It can be concluded that Hpk2 and Rrp2 constitute a functional two-component system that contributes to environmental sensing.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas Bacterianas/fisiología , Regulación Bacteriana de la Expresión Génica , Genes Reguladores , Treponema denticola/genética , Adaptación Fisiológica/genética , Proteínas Bacterianas/metabolismo , ADN Bacteriano/análisis , Histidina Quinasa , Sistemas de Lectura Abierta , Operón , Enfermedades Periodontales/microbiología , Fosforilación , Regiones Promotoras Genéticas , Proteínas Quinasas/metabolismo , Estructura Terciaria de Proteína , Análisis de Secuencia de ADN , Transactivadores/genética , Transcripción Genética , Treponema denticola/metabolismo
18.
J Nat Prod ; 73(4): 747-50, 2010 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-20302348

RESUMEN

A one-pot chemical process using BF(3).Et(2)O for the synthesis of a new class of 1(15-->11) abeotaxanes from normal taxanes has been developed. The chemical structures of rearranged 1(15-->11) abeotaxane were established by extensive 2D NMR spectroscopic data.


Asunto(s)
Taxoides , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Paclitaxel/química , Paclitaxel/aislamiento & purificación , Taxoides/síntesis química , Taxoides/química , Taxoides/clasificación
19.
Virus Genes ; 39(3): 335-41, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19669672

RESUMEN

Signaling Lymphocyte Activation Molecule-SLAM (CD150) molecule has been reported as a putative receptor for most morbilliviruses for their respective host species. In this study, we determined the complete nucleotide sequence of the gene coding for the morbillivirus receptor-SLAM from the four species, namely, goat (Capra hircus), sheep (Ovis aries), Indian cattle (Bos indicus), and buffalo (Bubalus bubalis). The nucleotide (nt) open reading frame sequence of SLAM gene in all the four species studied was 1017 nucleotides in length encoding a polypeptide of 339 amino acids (aa), similar to Bos taurus, but different from canine, human, marmoset, and mouse SLAM, which were 1029, 1008, 1011, and 1032 nts, respectively, in length, and coding for 343, 336, 337, and 344 aa, respectively. Sequence analysis revealed 96.3-98.5% and 92.9-96.8% identities among the four species at the nt and aa level, respectively. Sequence diversity at aa level between various species revealed that the critical functional region of SLAM protein among different species is relatively conserved, thereby facilitating this molecule to act as a receptor for morbillivirus. Phylogenetic relationship based on the aa sequences of SLAM protein revealed that caprine, ovine, cattle, and buffalo fall under a defined cluster but caprine SLAM is more closely related to ovine, followed by bovine.


Asunto(s)
Antígenos CD/genética , Morbillivirus , Polimorfismo Genético , Receptores de Superficie Celular/genética , Receptores Virales/genética , Animales , Búfalos , Bovinos , Análisis por Conglomerados , Cabras , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Ovinos , Miembro 1 de la Familia de Moléculas Señalizadoras de la Activación Linfocitaria
20.
Pharmacol Biochem Behav ; 90(4): 758-62, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18582496

RESUMEN

The partner preference paradigm was used to test the hypothesis that mild restraint reduced sexual motivation of female rats. Ovariectomized rats were primed with 10 pg estradiol benzoate or estradiol benzoate and 500 microg progesterone. Additional rats were injected with sesame seed oil. These three groups of rats (oil-oil, estradiol benzoate-oil, or estradiol benzoate-progesterone; OO, EO, EP) were placed for 10 min in an arena, the ends of which enclosed either a sexually active male or an ovariectomized, unprimed female. Time spent near the sexually active male relative to time spent near either stimulus animal was used as the index of male preference. As expected, hormonal treatment significantly increased male preference. After this first 10 min interval, females were returned to the home cage or restrained for 5 min in a Decapicone. Thereafter, male preference was recorded for another 10 min. Consistent with the first 10 min period, EP rats spent significantly more time near the male than did OO rats while EO rats were intermediate. There was no effect of restraint, but there was a significant increase in self-grooming. These findings contrast with previous studies and allow the suggestion that a brief, mild restraint fails to influence the female's sexual motivation. The implications of these findings are discussed.


Asunto(s)
Hormonas Esteroides Gonadales/fisiología , Conducta Sexual Animal/fisiología , Estrés Psicológico/psicología , Animales , Estradiol/análogos & derivados , Estradiol/farmacología , Femenino , Hormonas Esteroides Gonadales/farmacología , Masculino , Motivación , Ovariectomía , Progesterona/farmacología , Ratas , Ratas Endogámicas F344 , Restricción Física , Conducta Sexual Animal/efectos de los fármacos
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