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1.
Analyst ; 144(3): 928-934, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30412213

RESUMO

With lethal opportunistic fungal infections on the rise, it is imperative to explore new methods to examine virulence mechanisms. The fungal cell wall is crucial for both the virulence and viability of Aspergillus nidulans. One wall component, Galf, has been shown to contribute to important fungal processes, integrity of the cell wall and pathogenesis. Here, we explore gene deletion strains lacking the penultimate enzyme in Galf biosynthesis (ugmAΔ) and the protein that transports Galf for incorporation into the cell wall (ugtAΔ). In applying gene deletion technology to the problem of cell wall integrity, we have employed multiple micro- and nano-scale imaging tools, including confocal fluorescence microscopy, electron microscopy, X-Ray fluorescence and atomic force microscopy. Atomic force microscopy allows quantification of ultrastructural cell wall architecture while near-field infrared spectroscopy provides spatially resolved chemical signatures, both at the nanoscale. Here, for the first time, we demonstrate correlative data collection with these two emerging modalities for the multiplexed in situ study of the nanoscale architecture and chemical composition of fungal cell walls.


Assuntos
Aspergillus nidulans/ultraestrutura , Parede Celular/ultraestrutura , Proteínas Fúngicas/metabolismo , Galactose/metabolismo , Nanotecnologia/métodos , Espectrofotometria Infravermelho/métodos , Síncrotrons , Aspergillus nidulans/metabolismo , Parede Celular/metabolismo , Microscopia de Força Atômica/métodos , Microscopia de Fluorescência/métodos
2.
Clin Psychol Rev ; 67: 78-93, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30442478

RESUMO

OBJECTIVE: To review the therapist effects literature since Baldwin and Imel's (2013) review. METHOD: Systematic literature review of three databases (PsycINFO, PubMed and Web of Science) replicating Baldwin and Imel (2013) search terms. Weighted averages of therapist effects (TEs) were calculated, and a critical narrative review of included studies conducted. RESULTS: Twenty studies met inclusion criteria (3 RCTs; 17 practice-based) with 19 studies using multilevel modeling. TEs were found in 19 studies. The TE range for all studies was 0.2% to 29% (weighted average = 5%). For RCTs, 1%-29% (weighted average = 8.2%). For practice-based studies, 0.2-21% (weighted average = 5%). The university counseling subsample yielded a lower TE (2.4%) than in other groupings (i.e., primary care, mixed clinical settings, and specialist/focused settings). Therapist sample sizes remained lower than recommended, and few studies appeared to be designed specifically as TE studies, with too few examples of maximising the research potential of large routine patient datasets. CONCLUSIONS: Therapist effects are a robust phenomenon although considerable heterogeneity exists across studies. Patient severity appeared related to TE size. TEs from RCTs were highly variable. Using an overall therapist effects statistic may lack precision, and TEs might be better reported separately for specific clinical settings.


Assuntos
Pessoal de Saúde/estatística & dados numéricos , Transtornos Mentais/terapia , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Psicoterapia/estatística & dados numéricos , Humanos
3.
Chem Rev ; 118(6): 3121-3207, 2018 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-29400955

RESUMO

Localized surface plasmon resonance (LSPR) in semiconductor nanocrystals (NCs) that results in resonant absorption, scattering, and near field enhancement around the NC can be tuned across a wide optical spectral range from visible to far-infrared by synthetically varying doping level, and post synthetically via chemical oxidation and reduction, photochemical control, and electrochemical control. In this review, we will discuss the fundamental electromagnetic dynamics governing light matter interaction in plasmonic semiconductor NCs and the realization of various distinctive physical properties made possible by the advancement of colloidal synthesis routes to such NCs. Here, we will illustrate how free carrier dielectric properties are induced in various semiconductor materials including metal oxides, metal chalcogenides, metal nitrides, silicon, and other materials. We will highlight the applicability and limitations of the Drude model as applied to semiconductors considering the complex band structures and crystal structures that predominate and quantum effects that emerge at nonclassical sizes. We will also emphasize the impact of dopant hybridization with bands of the host lattice as well as the interplay of shape and crystal structure in determining the LSPR characteristics of semiconductor NCs. To illustrate the discussion regarding both physical and synthetic aspects of LSPR-active NCs, we will focus on metal oxides with substantial consideration also of copper chalcogenide NCs, with select examples drawn from the literature on other doped semiconductor materials. Furthermore, we will discuss the promise that LSPR in doped semiconductor NCs holds for a wide range of applications such as infrared spectroscopy, energy-saving technologies like smart windows and waste heat management, biomedical applications including therapy and imaging, and optical applications like two photon upconversion, enhanced luminesence, and infrared metasurfaces.

4.
Nano Lett ; 17(4): 2611-2620, 2017 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-28337921

RESUMO

Doped metal oxides are plasmonic materials that boast both synthetic and postsynthetic spectral tunability. They have already enabled promising smart window and optoelectronic technologies and have been proposed for use in surface enhanced infrared absorption spectroscopy (SEIRA) and sensing applications. Herein, we report the first step toward realization of the former utilizing cubic F and Sn codoped In2O3 nanocrystals (NCs) to couple to the C-H vibration of surface-bound oleate ligands. Electron energy loss spectroscopy is used to map the strong near-field enhancement around these NCs that enables localized surface plasmon resonance (LSPR) coupling between adjacent nanocrystals and LSPR-molecular vibration coupling. Fourier transform infrared spectroscopy measurements and finite element simulations are applied to observe and explain the nature of the coupling phenomena, specifically addressing coupling in mesoscale assembled films. The Fano line shape signatures of LSPR-coupled molecular vibrations are rationalized with two-port temporal coupled mode theory. With this combined theoretical and experimental approach, we describe the influence of coupling strength and relative detuning between the molecular vibration and LSPR on the enhancement factor and further explain the basis of the observed Fano line shape by deconvoluting the combined response of the LSPR and molecular vibration in transmission, absorption and reflection. This study therefore illustrates various factors involved in determining the LSPR-LSPR and LSPR-molecular vibration coupling for metal oxide materials and provides a fundamental basis for the design of sensing or SEIRA substrates.

5.
J Am Soc Mass Spectrom ; 28(7): 1462-1472, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28315237

RESUMO

N-terminal derivatization of peptides with the chromogenic reagent 4-acetamido-4-isothiocyanatostilbene-2,2-disulfonic acid (SITS) is demonstrated to enhance the efficiency of 266 nm ultraviolet photodissociation (UVPD). Attachment of the chromophore results in a mass shift of 454 Da and provides significant gains in the number and abundances of diagnostic fragment ions upon UVPD. Activation of SITS-tagged peptides with 266 nm UVPD leads to many fragment ions akin to the a/b/y ions commonly produced by CID, along with other sequence ions (c, x, and z) typically accessed through higher energy pathways. Extreme bias towards C-terminal fragment ions is observed upon activation of SITS-tagged peptides using multiple 266 nm laser pulses. Due to the high reaction efficiency of the isothiocyanate coupling to the N-terminus of peptides, we demonstrate the ability to adapt this strategy to a high-throughput LC-MS/MS workflow with 266 nm UVPD. Graphical Abstract ᅟ.

7.
Nat Commun ; 7: 11583, 2016 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-27174681

RESUMO

Infrared-responsive doped metal oxide nanocrystals are an emerging class of plasmonic materials whose localized surface plasmon resonances (LSPR) can be resonant with molecular vibrations. This presents a distinctive opportunity to manipulate light-matter interactions to redirect chemical or spectroscopic outcomes through the strong local electric fields they generate. Here we report a technique for measuring single nanocrystal absorption spectra of doped metal oxide nanocrystals, revealing significant spectral inhomogeneity in their mid-infrared LSPRs. Our analysis suggests dopant incorporation is heterogeneous beyond expectation based on a statistical distribution of dopants. The broad ensemble linewidths typically observed in these materials result primarily from sample heterogeneity and not from strong electronic damping associated with lossy plasmonic materials. In fact, single nanocrystal spectra reveal linewidths as narrow as 600 cm(-1) in aluminium-doped zinc oxide, a value less than half the ensemble linewidth and markedly less than homogeneous linewidths of gold nanospheres.

8.
Nano Lett ; 16(5): 3390-8, 2016 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27111427

RESUMO

Defects may tend to make crystals interesting but they do not always improve performance. In doped metal oxide nanocrystals with localized surface plasmon resonance (LSPR), aliovalent dopants and oxygen vacancies act as centers for ionized impurity scattering of electrons. Such electronic damping leads to lossy, broadband LSPR with low quality factors, limiting applications that require near-field concentration of light. However, the appropriate dopant can mitigate ionized impurity scattering. Herein, we report the synthesis and characterization of a novel doped metal oxide nanocrystal material, cerium-doped indium oxide (Ce:In2O3). Ce:In2O3 nanocrystals display tunable mid-infrared LSPR with exceptionally narrow line widths and the highest quality factors observed for nanocrystals in this spectral region. Drude model fits to the spectra indicate that a drastic reduction in ionized impurity scattering is responsible for the enhanced quality factors, and high electronic mobilities reaching 33 cm(2)V(-1) s(-1) are measured optically, well above the optical mobility for tin-doped indium oxide (ITO) nanocrystals. We investigate the microscopic mechanisms underlying this enhanced mobility with density functional theory calculations, which suggest that scattering is reduced because cerium orbitals do not hybridize with the In orbitals that dominate the bottom of the conduction band. Ce doping may also reduce the equilibrium oxygen vacancy concentration, further enhancing mobility. From the absorption spectra of single Ce:In2O3 nanocrystals, we determine the dielectric function and by simulation predict strong near-field enhancement of mid-IR light, especially around the vertices of our synthesized nanocubes.

9.
PLoS One ; 10(11): e0141475, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26536673

RESUMO

Piscine reovirus (PRV) is a double stranded non-enveloped RNA virus detected in farmed and wild salmonids. This study examined the phylogenetic relationships among different PRV sequence types present in samples from salmonids in Western Canada and the US, including Alaska (US), British Columbia (Canada) and Washington State (US). Tissues testing positive for PRV were partially sequenced for segment S1, producing 71 sequences that grouped into 10 unique sequence types. Sequence analysis revealed no identifiable geographical or temporal variation among the sequence types. Identical sequence types were found in fish sampled in 2001, 2005 and 2014. In addition, PRV positive samples from fish derived from Alaska, British Columbia and Washington State share identical sequence types. Comparative analysis of the phylogenetic tree indicated that Canada/US Pacific Northwest sequences formed a subgroup with some Norwegian sequence types (group II), distinct from other Norwegian and Chilean sequences (groups I, III and IV). Representative PRV positive samples from farmed and wild fish in British Columbia and Washington State were subjected to genome sequencing using next generation sequencing methods. Individual analysis of each of the 10 partial segments indicated that the Canadian and US PRV sequence types clustered separately from available whole genome sequences of some Norwegian and Chilean sequences for all segments except the segment S4. In summary, PRV was genetically homogenous over a large geographic distance (Alaska to Washington State), and the sequence types were relatively stable over a 13 year period.


Assuntos
Doenças dos Peixes/genética , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Filogenia , Infecções por Reoviridae/genética , Reoviridae/genética , Salmonidae/genética , Sequência de Aminoácidos , Animais , Animais Selvagens , Sequência de Bases , Canadá/epidemiologia , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/virologia , Genoma Viral , Geografia , Dados de Sequência Molecular , Noroeste dos Estados Unidos/epidemiologia , RNA Viral/genética , Reoviridae/classificação , Infecções por Reoviridae/epidemiologia , Infecções por Reoviridae/virologia , Salmonidae/virologia , Análise de Sequência de DNA/métodos , Homologia de Sequência de Aminoácidos
11.
J Microbiol Methods ; 79(1): 128-30, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19703500

RESUMO

This study compared an automated Escherichia coli and coliform detection system with the membrane filtration direct count technique for water testing. The automated instrument performed equal to or better than the membrane filtration test in analyzing E. coli-spiked samples and blind samples with interference from Proteus vulgaris or Aeromonas hydrophila.


Assuntos
Contagem de Colônia Microbiana/métodos , Enterobacteriaceae/isolamento & purificação , Escherichia coli/isolamento & purificação , Sistemas Automatizados de Assistência Junto ao Leito , Microbiologia da Água , Automação , Filtração/métodos
12.
Afr Health Sci ; 8(3): 180-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19357747

RESUMO

BACKGROUND: Hypothyroidism in utero leading to mental retardation is highly prevalent in developing countries where iodine deficiency and thiocyanate overload are combined. OBJECTIVE: To explore prevalence of IDD in Bamougoum, a mountain region of western Cameroon, by studying urinary iodine and thiocyanate excretion levels in children. METHODS: Bamougoum district in western Cameroon was selected for closer study due to its geographic location predisposing to iodine deficiency disorders (IDD). A comprehensive sampling strategy included 24-h urine samples collected over three days from 120 school-aged children. Urinary iodine and thiocyanate levels were measured by colorimetric methods. RESULTS: Twenty one percent of boys between the ages 3 and 19 were classified as iodine deficient. The prevalence of thiocyanate overload in the same population was found to be 20%. CONCLUSION: Presence of endemic iodine deficiency and excessive thiocyanate in the population indicates that the region is at risk of iodine deficiency disorder. A multifactorial approach that includes improvement of diet, increasing iodine and minimizing goitrogen substances intake, soil and crop improvement and an iodine supplementation program may help alleviate IDD in the affected area studied.


Assuntos
Hipotireoidismo Congênito/epidemiologia , Iodo/urina , Estado Nutricional , Tiocianatos/urina , Adolescente , Distribuição por Idade , Camarões/epidemiologia , Criança , Pré-Escolar , Colorimetria/métodos , Dieta , Feminino , Humanos , Iodo/deficiência , Masculino , Vigilância da População , Prevalência , Risco , Adulto Jovem
13.
Afr Health Sci ; 8(4): 227-33, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20589129

RESUMO

OBJECTIVES: Hypothyroidism in utero leading to mental retardation is highly prevalent and recurrent in developing countries where iodine deficiency and thiocyanate overload are combined. So, to explore and identify human population's risks for developing iodine deficiency disorders and their endemicity in Western Cameroon, with the aim to prevent this deficiency and to fight again it, urinary iodine and thiocyanate levels were determined. METHODS: The district of Bamougoum in Western Cameroon was selected for closer study due to its geographic location predisposing for iodine deficiency disorders (IDD). A comprehensive sampling strategy included 24-h urine samples collected over three days from 120 school-aged children. Urinary iodine and thiocyanate levels were measured by colorimetric methods. RESULTS: Twenty one percent of boys between the ages 3 and 19 were classified as iodine deficient. The prevalence of thiocyanate overload in the same population was found to be 20%. CONCLUSION: Presence of endemic iodine deficiency and excessive thiocyanate in the population indicates that the region is at risk of iodine deficiency disorder. A multifactorial approach that includes improvement of diet, increasing iodine and minimizing goitrogen substances intake, soil and crop improvement and an iodine supplementation program may help alleviate IDD in the affected area studied.


Assuntos
Dieta/efeitos adversos , Iodo/deficiência , Iodo/urina , Tiocianatos/urina , Adolescente , Distribuição por Idade , Camarões/epidemiologia , Criança , Pré-Escolar , Colorimetria , Feminino , Humanos , Masculino , Estado Nutricional , Vigilância da População , Prevalência , Risco , Doenças da Glândula Tireoide/epidemiologia , Doenças da Glândula Tireoide/etiologia
14.
Pancreas ; 34(1): 103-11, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17198191

RESUMO

OBJECTIVES: Diabetes is a serious health problem. It has been proposed that islet neogenesis from pancreatic progenitor cells may restore insulin secretion in diabetic mammals. Islet neogenesis- associated protein (INGAP) stimulates islet neogenesis; therefore, we hypothesized that it would stimulate islet neogenesis in dogs. METHODS: Forty nondiabetic beagle dogs were randomly divided into 4 groups. Group 1 received daily intramuscular injections of vehicle, whereas the other 3 groups received daily INGAP injections of 0.5, 1.5, or 10 mg/kg. After 30 days, pancreatic tissues were collected, and RNA and histological sections were analyzed. RESULTS: In dogs treated with 1.5 mg/kg INGAP, there was a significant (P < 0.001) increase in the percentage of insulin-positive cells (P < 0.001) and insulin gene expression. There was a trend to increased insulin-positive cells and gene expression with treatments of 0.5 and 10 mg/kg peptide. Protein gene product 9.5-positive cells were increased with treatment. CONCLUSIONS: These results indicate that INGAP stimulates cells in the pancreatic duct epithelium of healthy dogs (putative islet progenitor cells) to develop along a neuroendocrine pathway and form new islets in response to INGAP peptide. The INGAP might be an effective therapy for diabetes.


Assuntos
Antígenos de Neoplasias/farmacologia , Biomarcadores Tumorais/farmacologia , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/efeitos dos fármacos , Animais , Antígenos de Neoplasias/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/farmacocinética , Divisão Celular/efeitos dos fármacos , Cricetinae , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Cães , Feminino , Imunofluorescência , Injeções Intramusculares , Injeções Intravenosas , Ilhotas Pancreáticas/metabolismo , Lectinas Tipo C/genética , Masculino , Mesocricetus , Proteínas Associadas a Pancreatite , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacocinética , Proteínas Recombinantes de Fusão/farmacologia , Regeneração/efeitos dos fármacos
15.
Nurs Times ; 101(34): 26-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16149700

RESUMO

Whether there are enough practice placements and if they are of a high enough quality are questions that continue to come up and their resolution is vital for the future of the nursing workforce as a whole. In view of the vast increases in student numbers expected over the next few years, innovation, rather than traditional solutions, seems the only option. The priorities for future preregistration nurse education must therefore be clearly focused and integrated if the integrity of preregistration nursing is to be safeguarded.


Assuntos
Educação em Enfermagem/normas , Preceptoria/normas , Educação em Enfermagem/organização & administração , Humanos , Preceptoria/organização & administração , Reino Unido
16.
Arch Pathol Lab Med ; 127(3): 352-5, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12653583

RESUMO

In this report, we document the histologic and clinical features of a previously undefined spindle cell variant of ameloblastoma that eventually behaved in a malignant fashion during a protracted course. The predominant histologic pattern was a well-differentiated, cellular, spindled epithelial proliferation arising in the maxilla of a 14-year-old African American girl. Over 19 years, the patient experienced numerous local recurrences, metastases to distant bones after 15 years, and finally bulky local recurrence with intracranial extension resulting in death. This ameloblastic malignancy histologically simulates a low-grade true sarcoma or an ameloblastic sarcoma, but differs in that the extensive spindle cell proliferation is epithelial, characterized by strong cytokeratin immunoreactivity and negative vimentin staining.


Assuntos
Ameloblastoma/diagnóstico , Neoplasias Maxilomandibulares/diagnóstico , Sarcoma/diagnóstico , Adolescente , Ameloblastoma/secundário , Neoplasias Encefálicas/secundário , Fossa Craniana Média/patologia , Evolução Fatal , Feminino , Humanos , Neoplasias Maxilomandibulares/patologia , Maxila/patologia , Recidiva Local de Neoplasia/patologia , Sarcoma/secundário , Neoplasias da Base do Crânio/secundário , Lobo Temporal/patologia
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