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PubMed2005

Tufted apple bud moth (Lepidoptera: Tortricidae) management model for processing apples based on early season pheromone trap capture.

Sixteen years of archived tufted apple bud moth, Platynota idaeusalis (Walker), trap capture data were compared with archived fruit injury data collected at the Penn State University Fruit Research and Extension Center to define the relationship of trap capture to fruit injury. Pheromone trap capture until 15 June was the best predictor of fruit injury at harvest. Using the regression equation of fruit injury on early season trap capture, and other assumptions about insecticide cost and fruit yield, a management model was developed for apple growers in the Mid-Atlantic region. When the model was tested on archived trap capture and fruit injury data, the results indicated that a grower would lose money on average by always treating and save money on average by never treating. By using the model, a grower could expect to save more money than by never treating. The model showed sensitivity to fruit price, insecticide price, and fruit yield.

Animals↗

PubMed2004

An ultrasensitive capture ELISA for detection of Fasciola hepatica coproantigens in sheep and cattle using a new monoclonal antibody (MM3).

A capture enzyme-linked immunosorbent assay (ELISA) using a new monoclonal antibody (mAb MM3) is reported for the detection of Fasciola hepatica excretory-secretory antigens (ESAs) in feces of infected hosts. The mAb MM3 was produced by immunization of mice with a 7- to 40-kDa purified and O-deglycosylated fraction of F. hepatica ESAs, which has previously been shown to be specific for the parasite. The specificity and sensitivity of the MM3 capture ELISA were assessed using feces from sheep and cattle. Sheep feces were obtained from a fluke-free herd (with most animals harboring other nematodes and cestodes), from lambs experimentally infected with 5-40 F. hepatica metacercariae and in some cases treated with triclabendazole at 14 wk postinfection (PI), and from uninfected control lambs. Cattle feces were collected at the slaughterhouse from adult cows naturally infected with known numbers of flukes (from 1 to 154) or free of F. hepatica infection (though in most cases harboring other helminths). The MM3 capture ELISA assay had detection limits of 0.3 (sheep) and 0.6 (cattle) ng of F. hepatica ESA per milliliter of fecal supernatant. The assay detected 100% of sheep with 1 fluke, 100% of cattle with 2 flukes, and 2 of 7 cattle with 1 fluke. The false-negative animals (5/7) were probably not detected because the F. hepatica individuals in these animals were immature (5-11 mm in length). As expected, coproantigen concentration correlated positively (r = 0.889; P < 0.001) with parasite burden and negatively (r = 0.712; P < 0.01) with the time after infection at which coproantigen was first detected. Nevertheless, even in animals with low fluke burdens (1-36 parasites), the first detection of F. hepatica-specific coproantigens by the MM3 capture ELISA preceded the first detection in egg count by 1-5 wk. In all sheep that were experimentally infected and then untreated, coproantigen remained detectable until at least 18 wk PI, whereas in sheep that were experimentally infected and then flukicide treated, coproantigen became undetectable from 1 to 3 wk after treatment. None of the fecal samples from sheep or cattle negative for fascioliasis but naturally infected with other parasites including Dicroelium dendriticum showed reactivity in the MM3 capture ELISA. These results indicate that this assay is a reliable and ultrasensitive method for detecting subnanogram amounts of F. hepatica antigens in feces from sheep and cattle, facilitating early diagnosis.

Animals↗

PubMed2002

Anti-asialoglycoprotein receptor autoantibodies, detected by a capture-immunoassay, are associated with autoimmune liver diseases.

In autoimmune chronic active hepatitis (AIH) and primary biliary cirrhosis (PBC), various autoantibodies including anti-asialoglycoprotein receptor (ASGPR) antibodies have been found in patients' sera. We have previously developed a mouse monoclonal antibody against rat and human ASGPR. In this study, we developed a capture enzyme-linked immunosorbent assay (ELISA) for detection of anti-ASGPR antibodies using this monoclonal antibody and investigated the occurrence of anti-ASGPR antibodies in the sera of patients with various liver diseases. Serum samples were obtained from 123 patients with various liver diseases, including 21 patients with AIH and 40 patients with PBC. In this capture ELISA, the target antigen in the crude rat liver membrane extracts was captured on the ELISA wells by the ASGPR-specific mouse monoclonal antibody. Thus, the cumbersome process of antigen purification was rendered unnecessary. Using this capture ELISA, we detected the anti-ASGPR antibody in 67% of the patients with AIH, in 100% of the patients with PBC, and in 57% of the patients with acute hepatitis type A. However, the anti-ASGPR antibody was rarely detected in patients with other liver diseases such as primary sclerosing cholangitis and obstructive jaundice. Our findings suggest that this capture ELISA would be useful for the detection of anti-ASGPR antibodies in autoimmune liver diseases.

Adolescent↗

PubMed1994

Estimating the number of HIV-infected injection drug users in Bangkok: a capture--recapture method.

OBJECTIVES: The purpose of the study was to estimate the number of injection drug users infected with the human immunodeficiency virus (HIV) in Bangkok to allow planning for health services for this population. METHODS: A two-sample capture-recapture method was used. The first capture listed all persons on methadone treatment for opiate addiction from April 17 through May 17, 1991, at 18 facilities in Bangkok. The second capture involved urine testing of persons held at 72 Bangkok police stations from June 3 through September 30, 1991. Persons whose urine tests were positive for opiate metabolites or methadone were included on the second list. RESULTS: The first capture comprised 4064 persons and the recapture 1540 persons. There were 171 persons included on both lists, yielding an estimate of 36,600 opiate users in Bangkok. Existing data indicate that 89% of opiate users in Bangkok inject drugs and that about one third are infected with HIV, yielding an estimate of approximately 12,000 HIV-infected injection drug users in Bangkok in 1991. CONCLUSIONS: During the 1990s the number of cases of acquired immunodeficiency syndrome (AIDS) and other HIV-related diseases, including tuberculosis, in the population of HIV-infected injection drug users in Bangkok will increase dramatically, placing new demands on existing health care facilities. The capture-recapture method may be useful in estimating difficult-to-count populations, including injection drug users.

Data Collection↗

PubMed1997

Affinity purification of RNA: sequence-specific capture by nonionic morpholino probes.

Nucleic acid isolation for amplification-based diagnostics requires techniques that do not co-purify inhibitors of DNA polymerases. Also, other requirements for an ideal sample preparation technology include ease of use, capability for automation, high recovery and the use of nontoxic reagents. Affinity purification techniques provide high purification factor with minimal sample processing. Hybridization is the affinity interaction specific to nucleic acids and thus provides a uniquely advantageous method for purifying DNA or RNA for subsequent manipulation. Nonionic (morpholino) probes (Neu-Probes, AntiVirals, Corvallis, OR, USA) have several unique hybridization properties, including resistance to nucleases and the ability to hybridize independently of salt concentration. Therefore, such probes provide advantages over DNA probes for sample preparation by hybridization capture. Three formats for hybridization-based purification of human immunodeficiency virus (HIV) RNA were evaluated using RNA transcripts spiked into crude lysates of normal human plasma. Indirect capture used streptavidin-coated microparticles to capture hybrids of biotinylated capture probes and HIV RNA. Direct capture used particles precoated with probes. In addition, a novel method for acceleration of sequence-specific hybridization was developed and shown to give consistently high recoveries.

DNA-Directed DNA Polymerase↗

PubMed1999

Laser capture microdissection of single cells from complex tissues.

Laser capture microdissection (LCM) is a new method used to select and procure cell clusters from tissue sections. Once captured, the DNA, RNA or protein can be easily extracted from the isolated cells and analyzed by conventional PCR, reverse transcription (RT)-PCR or polyacrylamide gel electrophoresis, including protein zymography for specific macromolecular changes. In LCM, a thermoplastic polymer coating [ethylene vinyl acetate (EVA)] attached to a rigid support is placed in contact with a tissue section. The EVA polymer over microscopically selected cell clusters is precisely activated by a near-infrared laser pulse and then bonds to the targeted area. Removal of the EVA and its support from the tissue section procures the selected cell aggregates for molecular analysis. This initial NIH LCM approach using a flat transfer EVA film has been recently commercialized and has proven to be an effective routine microdissection technique for subsequent macromolecular analysis in many laboratories around the world. However, reliable and precise capture of individual cells from tissue sections has been difficult to perform with the current LCM instruments. In this report, we describe the capture of individual cells with a new NIH LCM microscope, which epi-irradiates the EVA polymer overlying individual cells with 1-ms laser pulses focused to 6 microns. A computer-controlled arm precisely positions a 40-micron-wide strip of a cylindrical EVA surface onto a sample with a light contact force (ca. 0.1 g). The small contact force and contact area on the film on the sample diminishes nonspecific transfer to negligible levels. By slightly rotating the cylinder to provide a renewable transfer surface, concentration of a distinct cell type on a single cylinder is possible. Using this novel adaptation, we demonstrate the rapid and practical capture of single cells from different types of tissue sections, including immunostained cells.

Animals↗

PubMed2006

Evaluation of factors associated with positive IgM capture ELISA results in equids with clinical signs compatible with West Nile virus infection: 1,017 cases (2003).

OBJECTIVE: To describe the prevalence of West Nile virus (WNV) infection and evaluate factors associated with positive IgM capture ELISA results in equids with clinical signs compatible with WNV infection. DESIGN: Retrospective case series. SAMPLE POPULATION: Laboratory submission forms from 1,104 equids tested for WNV in Colorado in 2003. PROCEDURES: Submission forms accompanying samples submitted for detection of WNV via IgM capture ELISA were obtained from the Colorado state veterinarian and diagnostic laboratories performing the tests. Data on signalment, clinical signs, history of vaccination against WNV, and assay results were collected from laboratory submission forms. Equids with clinical signs compatible with WNV infection in which IgM capture ELISA results were positive were considered as case equids. RESULTS: 1,104 equids were tested for WNV; 1,017 (92.1%) had clinical signs compatible with WNV infection. Among equids with clinical signs compatible with WNV infection, the odds of testing positive for WNV via IgM capture ELISA were lower in males and in vaccinated equids and higher in equids with moderate and severe illness, compared with females, unvaccinated equids, and equids with mild illness. CONCLUSIONS AND CLINICAL RELEVANCE: Among equids with clinical signs compatible with WNV infection, vaccination against WNV, severity of clinical signs, duration of illness, and region in Colorado were associated with increased risk of having a positive IgM capture ELISA result.

Animals↗

PubMed1975

Factors involved in visual capture.

Visual capture was explored using three types of vision-"touch" conflicts. The results indicated that the amount of visual capture differed for the three tasks. In one task (slant judgments) strong, but incomplete, visual capture occurred, in another (a length judgment task) an approximate compromise between the two modalities was found, and in the third task (texture judgments) a trend toward touch capture occurred. In two additional experiments using the slant task, the effects of brief training with one of the competing modalities and the effects of manipulating certain aspects of the stimulus display were explored. The bried training did not alter the resolution of the conflict but varying visual clarity and felt texture of the rod whose slant was being judged did affect visual capture.

Adult↗

PubMedDate not supplied

Dual captures of Colorado rodents: implications for transmission of hantaviruses.

We analyzed dual-capture data collected during longitudinal studies monitoring transmission and persistence of Sin Nombre virus in rodents in Colorado. Our data indicate that multiple captures (two or more rodents captured in a single trap) may not be random, as indicated by previous studies, but rather the result of underlying, species-specific social behavior or cohesiveness. In the pairs we captured, most often, rodents were of the same species, were male, and could be recaptured as pairs. Therefore, dual captures of rodents, which are unusual but not rare, tend to occur among certain species, and appear to be nonrandom, group-foraging encounters. These demographic and ecologic characteristics may have implications for the study of the transmission of hantaviruses.

Aging↗

PubMed2006

It's under control: top-down search strategies can override attentional capture.

Bacon and Egeth (1994) proposed that observed instances of attentional capture by feature singletons (e.g., color) were the result of a salience-based strategy adopted by subjects (singleton detection mode) and, thus, were not automatic. They showed that subjects could override capture by adopting strategies based on searching for specific target features (feature search mode). However, Theeuwes (2004) has recently argued that Bacon and Egeth's results arose from experimental confounds. He elaborated a model in which attentional capture must be expected when salient distractors fall within a spatial window of attention. According to Theeuwes's (2004) model, there exist two essential criteria for examining stimulus-driven capture. First, search latencies cannot increase with display size, since the search must be parallel; second, the salience of the irrelevant distractor must not be compromised by characteristics of the search display. Contrary to the predictions of Theeuwes's (2004) model, we provide evidence that involuntary capture can be overridden when both of these criteria are met. Our results are consistent with Bacon and Egeth's proposal.

Attention↗

PubMed2003

Attentional and oculomotor capture with static singletons.

Previous research has shown that in visual search static singletons have the ability to capture attention (Theeuwes, 1991a, 1992). The present study investigated whether these singletons also have the ability to capture the eyes. Participants had to make an eye movement and respond manually to a shape singleton while a color singleton was present. When participants searched for a unique shape while a unique color singleton was present there was strong attentional and oculomotor capture (Experiment 1). However, when participants searched for a specific-shape singleton (a green circle) when a specific-color singleton (a red element) had to be ignored, there was attentional capture but no oculomotor capture (Experiment 2). The results suggest that an attentional set for a specific feature value defining both the target and the distractor (as in Experiment 2) allows such a fast disengagement of attention from the location of the distractor that a saccade execution to that location is prevented.

Attention↗

PubMed2003

Moving and looming stimuli capture attention.

Attention capture is often operationally defined as speeded search performance when an otherwise nonpredictive stimulus happens to be the target of a visual search. That is, if a stimulus captures attention, it should be searched with priority even when it is irrelevant to the task. Given this definition, only the abrupt appearance of a new object (see, e.g., Jonides & Yantis, 1988) and one type of luminance contrast change (Enns, Austen, Di Lollo, Rauschenberger, & Yantis, 2001) have been shown to strongly capture attention. We show that translating and looming stimuli also capture attention. This phenomenon does not occur for all dynamic events: We also show that receding stimuli do not attract attention. Although the sorts of dynamic events that capture attention do not fit neatly into a single category, we speculate that stimuli that signal potentially behaviorally urgent events are more likely to receive attentional priority.

Adult↗

PubMed1995

Attention capture by contour onsets and offsets: no special role for onsets.

In five experiments, we investigated the power of targets defined by the onset or offset of one of an object's parts (contour onsets and offsets) either to guide or to capture visual attention. In Experiment 1, search for a single contour onset target was compared with search for a single contour offset target against a static background of distractors; no difference was found between the efficiency with which each could be detected. In Experiment 2, onsets and offsets were compared for automatic attention capture, when both occurred simultaneously. Unlike in previous studies, the effects of overall luminance change, new-object creation, and number of onset and offset items were controlled. It was found that contour onset and offset items captured attention equally well. However, display size effects on both target types were also apparent. Such effects may have been due to competition for selection between multiple onset and offset stimuli. In Experiments 3 and 4, single onset and offset stimuli were presented simultaneously and pitted directly against one another among a background of static distractors. In Experiment 3, we examined "guided search," for a target that was formed either from an onset or from an offset among static items. In Experiment 4, the onsets and offsets were uncorrelated with the target location. Similar results occurred in both experiments: target onsets and offsets were detected more efficiently than static stimuli which needed serial search; there remained effects of display size on performance; but there was still no advantage for onsets. In Experiment 5, we examined automatic attention capture by single onset and offset stimuli presented individually among static distractors. Again, there was no advantage for onset over offset targets and a display size effect was also present. These results suggest that, both in isolation and in competition, onsets that do not form new objects neither guide nor gain automatic attention more efficiently than offsets. In addition, in contrast to previous studies in which onsets formed new objects, contour onsets and offsets did not reliably capture attention automatically.

Adolescent↗

PubMed1994

The hematological profile of the mountain gazelle (Gazella gazella): variations with sex, age, capture method, season, and anesthesia.

Hematological parameters were measured in 408 blood samples collected over a 30-mo period from 254 captive mountain gazelles (Gazella gazella) in Saudi Arabia. We evaluated the influence of sex, age, capture method, and season, on these parameters. Evaluations also were made with a small number of anesthetized animals. Males had a significantly higher mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) than females. There was no observed neutrophil: lymphocyte ratio shift for either sex during the first months of life. The effects of different capture methods generally were similar in males and females and included a significantly lower MCV and MCH after quick capture. Animals undergoing slow capture had a significantly lower mean corpuscular hemoglobin concentration (MCHC), and very pronounced stress neutrophilia. We propose that this stress neutrophilia caused the permanently high neutrophil: lymphocyte ratio (62:36 average for all gazelles tested) and the lack of a neutrophil: lymphocyte shift in young animals. Erythrocyte counts were significantly higher in summer, while packed cell volume and hemoglobin concentration were the same in summer and winter; thus there was a significantly lower MCV and MCH, and a significantly higher MCHC in summer in both sexes. Fibrinogen varied significantly by sex, age, capture method, and anesthesia.

Aging↗

PubMed1999

Triple-site antigen capture ELISA for human myoglobin can be more effective than double-site assay.

Using a panel of monoclonal antibodies against human myoglobin (Mb), we have shown that the sensitivity of antigen-capture ELISA can be significantly increased by simultaneous immobilization of two cooperating capture monoclonal antibodies on a solid phase. This method ("triple-site ELISA") uses three monoclonal antibodies to different epitopes of the same antigen (two capture/one tracer) unlike the traditional double-site assay using one capture and one tracer monoclonal antibody. We developed double- and triple-site ELISA for Mb by varying the capture and tracer monoclonal antibodies. Triple-site assays showed 4-6-fold increase in sensitivity compared to the double-site assays. A model for this effect is suggested; according to the model, in triple-site ELISA, high-affinity cyclic configurations can be formed by an antigen, two capture monoclonal antibodies, and the surface of the solid phase.

Animals↗

PubMed1999

Laboratory diagnosis of dengue virus infection by reverse transcriptase polymerase chain reaction (RT-PCR) and IgM-capture enzyme-linked immunosorbent assay (ELISA).

Dengue virus infections are a major public health problem in most tropical and sub-tropical countries of the world. Dengue is occasionally imported by travelers who visit tropical areas and become infected with dengue virus. Laboratory diagnosis is essential for confirming the diagnosis of this virus. For purposes of confirmation, detection of specific IgM by IgM-capture enzyme-linked immunosorbent assay (ELISA) and of dengue virus genome by reverse transcriptase polymerase chain reaction (RT-PCR) have recently been used. In the present study, we tested serum specimens from dengue-suspected Japanese cases, by IgM-capture ELISA, RT-PCR, HI, and virus isolation. Serum samples collected before or on the day of defervescence were positive by RT-PCR, though no PCR-positive samples were obtained after fever day 1. IgM-capture ELISA was positive as early as disease day 4, and all samples but one were IgM-positive when collected on disease day 5 or later. In light of these findings, we recommend that both RT-PCR and IgM-capture ELISA be performed, irrespective of the stage of dengue illness. Combination of RT-PCR and IgM-capture ELISA increases the ability to diagnose dengue virus infection, even in the only that a single serum specimen from the patient is available.

Dengue↗

PubMed1999

Use of streamline chelating for capture and purification of poly-His-tagged recombinant proteins.

Expression of recombinant proteins with poly-histidine tags enables their convenient capture and purification using immobilized metal affinity chromatography (IMAC). The 6 x His-tagged protein binds to a chelating resin charged with metal ions such as Ni2+, Cu2+ or Zn2+, and can therefore be separated from proteins which have lower, or no, affinity for the resin. Two recombinant proteins, a malaria transmission-blocking vaccine candidate secreted extracellularly by S. cerevisiae and a modified diphtheria toxin produced intracellularly by E. coli, were expressed with 6 x His tags and could therefore be purified using IMAC. In an effort to further simplify the initial capture of these proteins, an expanded bed adsorption technique using a chelating resin (Streamline Chelating) was introduced. It was possible to capture the intracellular diphtheria protein from E. coli directly after cell lysis, without prior centrifugation or filtration. The extracellular malaria vaccine candidate was also directly captured from a high cell density yeast culture. Detailed information on the experimental work performed, and the capture processes developed, is provided.

Adsorption↗

PubMed2000

Quantitative detection of oncogenic HPV DNA using hybrid capture to triage borderline and mildly dyskaryotic Papanicolaou smears.

OBJECTIVE: To investigate the use of hybrid capture to triage borderline and mildly abnormal PAP smears to either colposcopy or continued cytological surveillance. METHOD: A prospective cross-sectional study of 207 women with either mild or borderline dyskaryosis referred to the colposcopy clinic at the Whittington Hospital, London was done. Quantitative detection of oncogenic human papillomavirus deoxyribose nucleic acid was performed using the solution hybridization technique Hybrid Capture I (Digene Diagnostics). Positive or negative hybrid capture results were compared to colposcopically directed punch biopsy or loop excision of the transformation zone. RESULTS: Hybrid capture correctly predicted 1/1 micro-invasive cancers, 23/24 CIN 3 and 20/24 CIN 2, giving a sensitivity to detect significant disease of CIN 2 or above of 90%. For CIN 1, 37/66 were HPV positive making the sensitivity to detect all grades of CIN 70%. Of women with a normal cervix, 39/92 were HPV positive and in total 58% of the women were HPV positive and would have been referred to colposcopy. CONCLUSIONS: Hybrid capture was a simple solution hybridization method which provided a sensitive method of detecting CIN 2 and above lesions in women with minor PAP smear abnormalities. However, the sensitivity for CIN 1 and the specificity were low, meaning that further improvements in the technique are needed before it can be used as a triage strategy.

Adolescent↗