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1.
A A Pract ; 14(11): e01315, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32985852

RESUMO

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.


Assuntos
Plexo Braquial , Síndrome de Guillain-Barré , Neuralgia , Estimulação Elétrica Nervosa Transcutânea , Adulto , Síndrome de Guillain-Barré/complicações , Síndrome de Guillain-Barré/terapia , Humanos , Masculino , Neuralgia/etiologia , Neuralgia/terapia , Adulto Jovem
2.
Sci Rep ; 8(1): 14952, 2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297734

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-29495725

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-28253685

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-27914378

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-27786173

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-27027476

RESUMO

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.


Assuntos
Resinas Acrílicas/farmacologia , Antineoplásicos/farmacologia , Técnicas de Cultura de Células/métodos , Criogéis/farmacologia , Gelatina/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Polímeros/farmacologia , Esferoides Celulares/citologia , Temperatura , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Esferoides Celulares/efeitos dos fármacos
8.
Persoonia ; 34: 167-266, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26240451

RESUMO

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.

9.
J Acoust Soc Am ; 138(1): EL54-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26233061

RESUMO

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.
Cell Death Dis ; 6: e1860, 2015 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-26313911

RESUMO

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.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Espécies Reativas de Oxigênio/agonistas , Solanina/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/efeitos dos fármacos , Família da Proteína 8 Relacionada à Autofagia , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Linhagem Celular Tumoral , Cloroquina/farmacologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Macrolídeos/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição de Fator Regulador X , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
11.
Early Child Dev Care ; 185(2): 291-316, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25632172

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-24890414

RESUMO

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.


Assuntos
Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica/genética , Doenças Periodontais/microbiologia , Regulon/genética , Fatores de Transcrição/genética , Treponema denticola/genética , Adaptação Fisiológica/genética , Técnicas Bacteriológicas , Biologia Computacional , Progressão da Doença , Ensaio de Desvio de Mobilidade Eletroforética , Genoma Bacteriano/genética , Humanos , Motivos de Nucleotídeos/genética , Regiões Promotoras Genéticas/genética , Sequências Reguladoras de Ácido Nucleico/genética , Análise de Sequência de DNA , Fator sigma/genética , Transcrição Gênica/genética
13.
Virusdisease ; 25(3): 408-11, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25674614

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-24750927

RESUMO

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.


Assuntos
Anti-Infecciosos , Bactérias/crescimento & desenvolvimento , Nanopartículas Metálicas/química , Prata , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Nanopartículas Metálicas/ultraestrutura , Tamanho da Partícula , Prata/química , Prata/farmacologia , Nitrato de Prata/química
15.
J Orthop Surg (Hong Kong) ; 19(3): 367-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22184173

RESUMO

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.


Assuntos
Lesões no Cotovelo , Fixação Interna de Fraturas , Ligamentos Articulares/cirurgia , Traumatismos do Punho/cirurgia , Acidentes por Quedas , Adulto , Fios Ortopédicos , Descompressão Cirúrgica , Articulação do Cotovelo/diagnóstico por imagem , Fixação Interna de Fraturas/métodos , Humanos , Luxações Articulares , Masculino , Radiografia , Traumatismos do Punho/diagnóstico por imagem , Articulação do Punho/diagnóstico por imagem
16.
J Dent Res ; 90(10): 1155-63, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21447698

RESUMO

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.


Assuntos
Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Bolsa Periodontal/microbiologia , Transdução de Sinais/genética , Treponema denticola/genética , Adaptação Fisiológica , Animais , Sequência de Bases , GMP Cíclico/análogos & derivados , GMP Cíclico/fisiologia , RNA Polimerases Dirigidas por DNA/genética , Histidina Quinase , Humanos , Proteínas Quinases/genética , Fator sigma/genética , Treponema denticola/fisiologia
17.
Mol Oral Microbiol ; 25(4): 241-51, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20618698

RESUMO

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.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Regulação Bacteriana da Expressão Gênica , Genes Reguladores , Treponema denticola/genética , Adaptação Fisiológica/genética , Proteínas de Bactérias/metabolismo , DNA Bacteriano/análise , Histidina Quinase , Fases de Leitura Aberta , Óperon , Doenças Periodontais/microbiologia , Fosforilação , Regiões Promotoras Genéticas , Proteínas Quinases/metabolismo , Estrutura Terciária de Proteína , Análise de Sequência de DNA , Transativadores/genética , Transcrição Gênica , Treponema denticola/metabolismo
18.
J Nat Prod ; 73(4): 747-50, 2010 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-20302348

RESUMO

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.


Assuntos
Taxoides , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Paclitaxel/química , Paclitaxel/isolamento & purificação , Taxoides/síntese química , Taxoides/química , Taxoides/classificação
19.
Virus Genes ; 39(3): 335-41, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19669672

RESUMO

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.


Assuntos
Antígenos CD/genética , Morbillivirus , Polimorfismo Genético , Receptores de Superfície Celular/genética , Receptores Virais/genética , Animais , Búfalos , Bovinos , Análise por Conglomerados , Cabras , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Ovinos , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária
20.
Pharmacol Biochem Behav ; 90(4): 758-62, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18582496

RESUMO

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.


Assuntos
Hormônios Esteroides Gonadais/fisiologia , Comportamento Sexual Animal/fisiologia , Estresse Psicológico/psicologia , Animais , Estradiol/análogos & derivados , Estradiol/farmacologia , Feminino , Hormônios Esteroides Gonadais/farmacologia , Masculino , Motivação , Ovariectomia , Progesterona/farmacologia , Ratos , Ratos Endogâmicos F344 , Restrição Física , Comportamento Sexual Animal/efeitos dos fármacos
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