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3.
QJM ; 109(8): 553-4, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27289114
5.
Appl Opt ; 53(13): C54-63, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24921890

RESUMO

System requirements for many military electro-optic and IR camera systems reflect the need for both wide-field-of-view situational awareness as well as high-resolution imaging for target identification. In this work we present a new imaging system architecture designed to perform both functions simultaneously and the AWARE 10 camera as an example at visible wavelengths. We first describe the basic system architecture and user interface followed by a laboratory characterization of the system optical performance. We then describe a field experiment in which the camera was used to identify several maritime targets at varying range. The experimental results indicate that users of the system are able to correctly identify ~10 m targets at between 4 and 6 km with 70% accuracy.

6.
Nature ; 486(7403): 386-9, 2012 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-22722199

RESUMO

Pixel count is the ratio of the solid angle within a camera's field of view to the solid angle covered by a single detector element. Because the size of the smallest resolvable pixel is proportional to aperture diameter and the maximum field of view is scale independent, the diffraction-limited pixel count is proportional to aperture area. At present, digital cameras operate near the fundamental limit of 1-10 megapixels for millimetre-scale apertures, but few approach the corresponding limits of 1-100 gigapixels for centimetre-scale apertures. Barriers to high-pixel-count imaging include scale-dependent geometric aberrations, the cost and complexity of gigapixel sensor arrays, and the computational and communications challenge of gigapixel image management. Here we describe the AWARE-2 camera, which uses a 16-mm entrance aperture to capture snapshot, one-gigapixel images at three frames per minute. AWARE-2 uses a parallel array of microcameras to reduce the problems of gigapixel imaging to those of megapixel imaging, which are more tractable. In cameras of conventional design, lens speed and field of view decrease as lens scale increases, but with the experimental system described here we confirm previous theoretical results suggesting that lens speed and field of view can be scale independent in microcamera-based imagers resolving up to 50 gigapixels. Ubiquitous gigapixel cameras may transform the central challenge of photography from the question of where to point the camera to that of how to mine the data.


Assuntos
Fotografação/instrumentação , Fotografação/métodos , Animais , Aves , Mineração de Dados , Eletrônica/instrumentação , Lagos , Fenômenos Ópticos , Óptica e Fotônica/instrumentação , Astros Celestes , Fatores de Tempo
7.
GHA Today ; 53(2): 2-3, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19862859
9.
Diabet Med ; 25(10): 1204-10, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19046199

RESUMO

AIM: Multiple medicines are typically prescribed for patients with Type 2 diabetes (T2D) and cardiovascular disease (CVD). Non-adherence to medicines can arise for those who self-manage the complex regimens typical of T2D and CVD. Perceptions about treatment and illness are probable drivers of adherence and self-management behaviours. However, few studies have explored perceptions about multiple medicines and none has examined the complexities of managing medicines used in T2D and CVD. We explored perceptions towards multiple medicines expressed by people managing co-morbid T2D and CVD. METHOD: Nineteen adults managing multiple medicines for T2D and CVD participated in semi-structured interviews. The interviews were analysed using a modified grounded theory framework. RESULTS: Participants were sceptical about the prescription of additional medicines, particularly CVD medicines. Often medicines for T2D management were thought to be more important than medicines prescribed for CVD management. Lifestyle change was thought to be a way of reducing CVD risk and this was related to the lower status given to CVD medication. Lipid-lowering medicines were often thought to be the least important CVD medication prescribed, with some participants considering cessation of medicines to test their necessity. CONCLUSIONS: Despite evidence on the severity of macrovascular complications in T2D being available, participants in this study undervalued their CVD medications. Survey research is needed to assess how widely held these beliefs are and whether these beliefs influence non-adherence. Future research should explore how healthcare professionals can best address such beliefs.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/psicologia , Cultura , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/psicologia , Adulto , Doenças Cardiovasculares/complicações , Quimioterapia Combinada , Feminino , Humanos , Entrevista Psicológica , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente
10.
Phytopathology ; 97(5): 592-7, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-18943578

RESUMO

ABSTRACT Fusarium head blight (FHB) caused by Fusarium graminearum is one of the most destructive diseases of durum (Triticum turgidum sp. durum) and common wheat (T. aestivum). Promising sources of FHB resistance have been identified among common (hexaploid) wheats, but the same is not true for durum (tetraploid) wheats. A previous study indicated that chromosome 7A from T. turgidum sp. dicoccoides accession PI478742 contributed significant levels of resistance to FHB. The objectives of this research were to develop a genetic linkage map of chromosome 7A in a population of 118 recombinant inbred lines derived from a cross between the durum cv. Langdon (LDN) and a disomic LDN-T. turgidum sp. dicoccoides PI478742 chromosome 7A substitution line [LDN-DIC 7A(742)], and identify a putative FHB resistance quantitative trait locus (QTL) on chromosome 7A derived from LDN-DIC 7A(742). The population was evaluated for type II FHB resistance in three greenhouse environments. Interval regression analysis indicated that a single QTL designated Qfhs.fcu-7AL explained 19% of the phenotypic variation and spanned an interval of 39.6 cM. Comparisons between the genetic map and a previously constructed physical map of chromosome 7A indicated that Qfhs.fcu-7AL is located in the proximal region of the long arm. This is only the second FHB QTL to be identified in a tetraploid source, and it may be useful to combine it with the QTL Qfhs.ndsu-3AS in order to develop durum wheat germ plasm and cultivars with higher levels of FHB resistance.

11.
Theor Appl Genet ; 112(8): 1473-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16544125

RESUMO

Four wheat (Triticum aestivum L.)-Thinopyrum ponticum derivatives SS5 (PI604926), SS156 (PI604947), SS363 (PI604970), and SS660 (PI604879), were identified as resistant to Fusarium head blight (FHB), a serious fungal disease of wheat worldwide. Seedling reactions to tan spot and Stagonospora nodorum blotch (SNB), two important foliar diseases of wheat, suggest that these four derivatives are resistant to tan spot and two of them (SS5 and SS156) are resistant to SNB. Fluorescent genomic in situ hybridization (FGISH) patterns of mitotic chromosomes indicate that these four derivatives are partial wheat-Th. ponticum amphiploids, each with a total of 56 chromosomes, though with different amounts of Th. ponticum chromatin. These four amphiploids were hybridized with each other to determine homology between the Th. ponticum genomes in each of the amphiploids. Analysis of chromosome pairing in the F1 hybrids using FGISH suggests that each amphiploid carries a similar set of Th. ponticum chromosomes. These wheat-Th. ponticum amphiploids represent a potential novel source of resistance to FHB, tan spot, and SNB for wheat breeding.


Assuntos
Cromossomos de Plantas , Fusarium/genética , Doenças das Plantas/genética , Triticum/genética , Análise Citogenética , Estudos de Avaliação como Assunto , Genoma de Planta , Hibridização Genética , Imunidade Inata/genética , Hibridização in Situ Fluorescente , Doenças das Plantas/microbiologia
13.
Theor Appl Genet ; 106(6): 1027-31, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12671750

RESUMO

During the past decade Fusarium head blight (FHB) caused by Fusarium graminearum Schwabe has resulted in severe grain yield and quality losses of wheat (Triticum aestivum L.) in the Northern Great Plains of the U.S. Given the complexity of breeding for FHB resistance, molecular markers associated with this trait will be valuable in accelerating efforts to breed resistant cultivars. The objective of this study was to identify molecular markers linked to quantitative trait loci (QTL) for FHB resistance in wheat using a set of lines obtained by several cycles of crossing to North Dakota adapted genotypes, which derived their resistance from cv. Sumai 3. Microsatellite markers spanning the wheat genome were used to screen parents and derived lines. Polymorphisms for parental alleles were compared to disease scores for Type II resistance. The probability of linkage between markers and introgressed resistance genes was calculated using a binomial probability formula based on the assumption that a molecular marker at a specific distance from the introgressed gene, in a near-isogenic line (NIL), will carry the donor-parent allele as a function of the distance between marker and gene and the number of backcrosses/selfs performed in deriving the NIL. Microsatellite loci Xgwm533 and Xgwm274 were significantly associated with QTL for FHB resistance.


Assuntos
Fusarium , Locos de Características Quantitativas , Triticum/genética , Interpretação Estatística de Dados , Repetições de Microssatélites , North Dakota , Triticum/microbiologia
14.
Plant Mol Biol ; 48(5-6): 625-32, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11999839

RESUMO

The devastating effect of Fusarium head blight (FHB) caused by Fusarium graminearum has led to significant financial losses across the Upper Midwest of the USA. These losses have spurred the need for research in biological, chemical, and genetic control methods for this disease. To date, most of the research on FHB resistance has concentrated on hexaploid wheat (Triticum aestivum L.) lines originating from China. Other sources of resistance to FHB would be desirable. One other source of resistance for both hexaploid wheat and tetraploid durum wheat (T. turgidum L. var. durum) is the wild tetraploid, T. turgidum L. var. dicoccoides (T. dicoccoides). Previous analysis of the 'Langdon'-T. dicoccoides chromosome substitution lines, LDN(Dic), indicated that the chromosome 3A substitution line expresses moderate levels of resistance to FHB. LDN(Dic-3A) recombinant inbred chromosome lines (RICL) were used to generate a linkage map of chromosome 3A with 19 molecular markers spanning a distance of 155.2 cM. The individual RICL and controls were screened for their FHB phenotype in two greenhouse seasons. Analysis of 83 RICL identified a single major quantitative trait locus, Qfhs.ndsu-3AS, that explains 37% of the phenotypic or 55% of the genetic variation for FHB resistance. A microsatellite locus, Xgwm2, is tightly linked to the highest point of the QTL peak. A region of the LDN (Dic-3A) chromosome associated with the QTL for FHB resistance encompasses a 29.3 cM region from Xmwg14 to Xbcd828.


Assuntos
Fusarium/crescimento & desenvolvimento , Doenças das Plantas/genética , Poliploidia , Característica Quantitativa Herdável , Triticum/genética , Mapeamento Cromossômico , DNA de Plantas/genética , Fusarium/patogenicidade , Genes de Plantas/genética , Marcadores Genéticos , Genótipo , Doenças das Plantas/microbiologia , Polimorfismo de Fragmento de Restrição , Triticum/microbiologia
15.
Biochim Biophys Acta ; 1528(2-3): 127-34, 2001 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-11687299

RESUMO

A 34-amino-acid peptide has been chemically synthesized based on a sequence from human alpha-fetoprotein. The purified peptide is active in anti-growth assays when freshly prepared in pH 7.4 buffer at 0.20 g/l, but this peptide slowly becomes inactive. This functional change is proven by mass spectrometry to be triggered by the formation of an intrapeptide disulfide bond between the two cysteine residues on the peptide. Interpeptide cross-linking does not occur. The active and inactive forms of the peptide have almost identical secondary structures as shown by circular dichroism (CD). Zinc ions bind to the active peptide and completely prevents formation of the inactive form. Cobalt(II) ions also bind to the peptide, and the UV-Vis absorption spectrum of the cobalt-peptide complex shows that: (1) a near-UV sulfur-to-metal-ion charge-transfer band had a molar extinction coefficient consistent with two thiolate bonds to Co(II); (2) the lowest-energy visible d-d transition maximum at 659 nm, also, demonstrated that the two cysteine residues are ligands for the metal ion; (3) the d-d molar extinction coefficient showed that the metal ion-ligand complex was in a distorted tetrahedral symmetry. The peptide has two cysteines, and it is speculated that the other two metal ion ligands might be the two histidines. The Zn(II)- and Co(II)-peptide complexes had similar peptide conformations as indicated by their ultraviolet CD spectra, which differed very slightly from that of the free peptide. Surprisingly, the cobalt ions acted in the reverse of the zinc ions in that, instead of stabilizing anti-growth form of the peptide, they catalyzed its loss. Metal ion control of peptide function is a saliently interesting concept. Calcium ions, in the conditions studied, apparently do not bind to the peptide. Trifluoroethanol and temperature (60 degrees C) affected the secondary structure of the peptide, and the peptide was found capable of assuming various conformations in solution. This conformational flexibility may possibly be related to the biological activity of the peptide.


Assuntos
Peptídeos/síntese química , alfa-Fetoproteínas/química , Cátions , Cromatografia em Gel , Dicroísmo Circular , Cobalto/química , Dissulfetos/química , Metais/química , Peptídeos/química , Peptídeos/fisiologia , Conformação Proteica , Estrutura Secundária de Proteína , Soluções , Espectrofotometria , Espectrofotometria Ultravioleta , Zinco/química
16.
JSLS ; 5(3): 221-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11548826

RESUMO

BACKGROUND: The use of advanced laparoscopy remains controversial in the field of surgical oncology because the potential for port-site recurrence may violate sound oncologic principles. Two mechanisms are theorized to be the cause of port-site recurrences: first, indirect contamination caused by pneumoperitoneum, aerosolization, or intraperitoneal spread, and second, direct contamination by physical trocar seeding. METHODS: A VX-2 carcinoma cell suspension was transferred under the left renal capsule of 31 rabbits with either an open flank incision (16) or laparoscopy (15). Animals were observed for tumor recurrence at the video port, the working port, and the open incision. Intraoperative findings and necropsy were used to document recurrence. RESULTS: The open incision technique resulted in local tumor recurrence in 1/16 animals with 16/16 viable intraabdominal tumors. The laparoscopic technique resulted in 0/15 video port-site recurrences and 9/15 working port-site recurrences, with 14/15 viable intraabdominal tumors. Recurrence at the laparoscopic working port occurred more frequently than in the open (P < 0.02) or laparoscopic video port groups (P < 0.007). No significant difference existed in recurrence between the open incision and the laparoscopic video port (P > 0.5). CONCLUSIONS: Laparoscopic port-site recurrences can be reproduced using the transplantable VX-2 rabbit carcinoma model. In the VX-2 model, trocar recurrence is the result of direct contamination via surgical instrumentation of viable tumor cells. The effect of the pneumoperitoneum or intraperitoneal cytological spillage (indirect contamination) does not have any effect on trocar recurrence. This model can be used to test and improve laparoscopic techniques to minimize the risk of port-site recurrence. Until technological advances have eliminated the risk of trocar recurrences, direct contact between malignant cells and laparoscopic instruments should be performed with caution.


Assuntos
Modelos Animais de Doenças , Laparoscopia/efeitos adversos , Inoculação de Neoplasia , Punções , Animais , Neoplasias Colorretais/patologia , Masculino , Neoplasias Pancreáticas/patologia , Pneumoperitônio Artificial , Coelhos , Distribuição Aleatória
17.
Infect Immun ; 69(9): 5777-85, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11500455

RESUMO

The environmental signals that affect gene regulation in Mycobacterium tuberculosis remain largely unknown despite their importance to tuberculosis pathogenesis. Other work has shown that several promoters, including acr (also known as hspX) (alpha-crystallin homolog), are upregulated in shallow standing cultures compared with constantly shaking cultures. Each of these promoters is also induced to a similar extent within macrophages. The present study used two-dimensional gel electrophoresis and mass spectrometry to further characterize differences in mycobacterial protein expression during growth under standing and shaking culture conditions. Metabolic labeling of M. bovis BCG showed that at least 45 proteins were differentially expressed under standing and shaking culture conditions. Rv2623, CysA2-CysA3, Gap, and Acr were identified from each of four spots or gel bands that were specifically increased in bacteria from standing cultures. An additional standing-induced spot contained two comigrating proteins, GlcB and KatG. The greatest induction was observed with Rv2623, a 32-kDa protein of unknown function that was strongly expressed under standing conditions and absent in shaking cultures. Analysis using PROBE, a multiple sequence alignment and database mining tool, classified M. tuberculosis Rv2623 as a member of a novel class of ATP-binding proteins that may be involved in M. tuberculosis's response to environmental signals. These studies demonstrate the power of combined proteomic and computational approaches and demonstrate that subtle differences in bacterial culture conditions may have important implications for the study of gene expression in mycobacteria.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Regulação Bacteriana da Expressão Gênica , Mycobacterium bovis/crescimento & desenvolvimento , Mycobacterium bovis/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Transporte/química , Proteínas de Transporte/genética , Biologia Computacional/métodos , Meios de Cultura , Eletroforese em Gel Bidimensional , Espectrometria de Massas/métodos , Dados de Sequência Molecular , Proteínas de Ligação a Fosfato , Proteoma , Análise de Sequência de DNA
18.
Am Heart J ; 142(2): 314-23, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11479472

RESUMO

BACKGROUND: Stenting improves the acute results of percutaneous balloon angioplasty for atherosclerotic renal artery stenosis. Predictors of benefit and angiographic restenosis are not well understood. We describe the technical and clinical success of renal artery stenting in a large consecutive series of patients with hypertension or renal insufficiency. We identify clinical, procedural, and anatomic factors that might influence outcome, restenosis, and survival. METHODS: Primary renal artery stenting was performed in 300 consecutive patients who underwent 363 stent procedures in 358 arteries. Angiograms were analyzed quantitatively. Clinical and angiographic follow-up data are available after a median of 16.0 months. RESULTS: At baseline, 87% of patients had hypertension, and 37% had chronic renal insufficiency. The mean age was 70 years (interquartile range 63.1-74.6) years. The stenosis was unilateral in 49% and bilateral in 48% and involved a solitary functioning kidney in 3.6%. The stenting procedure was successful in all attempts. There were no procedural deaths or emergency renal surgical procedures. Postprocedure azotemia was seen in 45 of 363 (12%) procedures but persisted in only 6 patients (2%), all of whom had baseline renal insufficiency. Systolic and diastolic blood pressures were significantly reduced (systolic blood pressure from 164.0 +/- 28.7 to 142.4 +/- 19.1 mm Hg, P <.001). At follow-up, 70% of patients had improved blood pressure control regardless of renal function. In patients with baseline renal insufficiency, 19% had improvement in serum creatinine levels at follow-up, 54% had stabilization, and 27% had deterioration. Follow-up mortality was 10% and was predicted by baseline creatinine levels (odds ratio 1.72 for each 1 mg/dL creatinine increment, 95% confidence interval 1.13-2.49) and extent of coronary artery disease (odds ratio 1.66 for each diseased coronary artery, 95% confidence interval 1.03-2.67). Angiographic restenosis was found in 21% of 102 patients overall and was less common (12%) in arteries with a reference caliber >4.5 mm (P <.01 vs caliber <4.5 mm). Neither poststenotic dilation nor severity of angiographic stenosis predicted clinical outcome. CONCLUSIONS: Primary renal artery stenting can be performed safely with nearly uniform technical success. The majority of patients with hypertension or renal insufficiency derive benefit. Follow-up mortality is 5-fold higher in patients with baseline renal insufficiency. Clinical and angiographic features did not predict blood pressure or renal functional outcome. Restenosis is more common in renal arteries with a reference caliber less than 4.5 mm.


Assuntos
Angioplastia Coronária com Balão , Arteriosclerose/terapia , Avaliação de Resultados em Cuidados de Saúde , Obstrução da Artéria Renal/terapia , Stents , Idoso , Angiografia , Arteriosclerose/mortalidade , Feminino , Humanos , Hipertensão Renal , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Obstrução da Artéria Renal/mortalidade , Insuficiência Renal
19.
Catheter Cardiovasc Interv ; 53(2): 264-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11387618

RESUMO

A 33-year-old woman with subacute thrombosis of the distal aorta after aorto-bi-iliac stenting had local thrombolysis with reteplase in conjunction with systemic abciximab. The infusion was given as a bolus and then continuously for 14 hr by radial artery access with two selective kissing catheters. Patency of the stented segments was achieved with this technique in conjunction with resolution of her clinical symptoms.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticoagulantes/uso terapêutico , Fibrinolíticos/uso terapêutico , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Infusões Intra-Arteriais/métodos , Proteínas Recombinantes/uso terapêutico , Terapia Trombolítica , Trombose/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Abciximab , Adulto , Aortografia , Feminino , Humanos , Artéria Radial
20.
Nucleic Acids Res ; 29(8): E41-1, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11292855

RESUMO

The cDNA microarray is one technological approach that has the potential to accurately measure changes in global mRNA expression levels. We report an assessment of an optimized cDNA microarray platform to generate accurate, precise and reliable data consistent with the objective of using microarrays as an acquisition platform to populate gene expression databases. The study design consisted of two independent evaluations with 70 arrays from two different manufactured lots and used three human tissue sources as samples: placenta, brain and heart. Overall signal response was linear over three orders of magnitude and the sensitivity for any element was estimated to be 2 pg mRNA. The calculated coefficient of variation for differential expression for all non-differentiated elements was 12-14% across the entire signal range and did not vary with array batch or tissue source. The minimum detectable fold change for differential expression was 1.4. Accuracy, in terms of bias (observed minus expected differential expression ratio), was less than 1 part in 10 000 for all non-differentiated elements. The results presented in this report demonstrate the reproducible performance of the cDNA microarray technology platform and the methods provide a useful framework for evaluating other technologies that monitor changes in global mRNA expression.


Assuntos
DNA Complementar/genética , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Sequência com Séries de Oligonucleotídeos/normas , RNA Mensageiro/análise , Análise de Variância , Encéfalo/metabolismo , Calibragem , Corantes , Sondas de DNA/biossíntese , Sondas de DNA/genética , DNA Complementar/biossíntese , Humanos , Miocárdio/metabolismo , Placenta/metabolismo , Reação em Cadeia da Polimerase , Controle de Qualidade , RNA Mensageiro/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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