SEARCH · PubMed Health

Results for “multiplex imaging”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources

PubMed2002

Characterization of a focal plane camera fitted to a Mattauch-Herzog geometry mass spectrograph. 1. Use with a glow-discharge source.

A Mattauch-Herzog geometry mass spectrograph (MHMS) has been equipped with a novel array detector, the focal plane camera (FPC). The FPC consists of an array of gold Faraday cups, each coupled to its own integrator, with interrogation of the integrators performed by a multiplexer. The initial coupling of this instrument with a pin-type glow discharge source has provided limits of detection in the single to hundreds of nanograms per gram regime; isotope ratio accuracy and precision better than 5% error and 0.2% RSD, respectively; and a linear dynamic range of at least 6 orders of magnitude. A current weakness of the FPC is its pixel size, which limits both sensitivity and baseline resolution (to R = 130). The minimum data acquisition time for multiple images at present is 1 ms/image, with a dead time of 3.2 ms between images, which will limit the ability of the FPC to monitor extremely short transient signals.

Journal Article↗

PubMed2002

Metabolic regulation of collagen I in fibroblasts isolated from normal peritoneum and adhesions by dichloroacetic acid.

OBJECTIVE: We have previously demonstrated that collagen I, a major component of postoperative adhesions, is differentially regulated in fibroblasts isolated from normal human peritoneum and adhesions. Collagen I messenger RNA (mRNA) levels are significantly lower in fibroblasts from normal peritoneum compared with levels from adhesion fibroblasts. This variation is further accentuated by hypoxia. Because adhesions provide a means of supplying oxygen and nutrients to postsurgical ischemic tissue, we sought to examine the role of aerobic metabolism in the differential expression of collagen I. To examine this issue, we used a compound, dichloroacetic acid (DCA), that stimulates pyruvate dehydrogenase, causing pyruvate to be metabolized in the Kreb's cycle rather than converted into lactate, thereby switching anaerobic to aerobic metabolism. Specifically, we have exposed human fibroblast cultures from normal peritoneum and adhesions to DCA (0, 50, and 100 microg/mL) for 24 hours under normal and hypoxic (2% oxygen) conditions. STUDY DESIGN: Multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) of collagen I and beta-actin was performed by using mRNA extracted from all treatment points. Analysis of PCR-amplified products was performed by fractionation over a 2% agarose gel, followed by ethidium bromide staining of DNA bands. A scanning densimeter was used to determine the ratio of intensity of each band relative to beta-actin. Densimetric analysis of gel bands was performed by using the National Institutes of Health image analysis program. RESULTS: Although DCA stimulated peritoneal fibroblast collagen I mRNA expression under normoxic conditions, its expression was reduced during hypoxia. In adhesion fibroblasts, DCA treatment consistently lowered collagen I mRNA expression; this effect was manifested to a greater extent under hypoxic conditions. CONCLUSION: In summary, these findings confirm that fibroblasts from adhesions are characterized by excessive collagen I production, which is further accentuated by hypoxia. These observations are extended to show the stimulation of oxidative metabolism by DCA increases collagen I production; in contrast DCA inhibits collagen I production by normoxic adhesion fibroblasts as well as under hypoxic conditions in both types of fibroblasts. Thus, regulation of metabolic activity of peritoneal cells may provide a target for future interventions for reduction of postoperative adhesions.

Cells, Cultured↗

PubMed1992

A fiber-optic broadband CT/MR video communication system.

Our department operates three magnetic resonance (MR) and three computed tomography (CT) scanners that are located in three different buildings up to 2 km apart. We have designed and implemented a multichannel, fiber-optic broadband video communication system as a remote scanner monitoring network. This system consists of baseband and broadband fiberoptic transmitters, receivers, and multiplexers. The structure of the video network is supported by two strategically located headends (distributors) connecting local/remote scanners and monitoring stations. The system is capable of serving up to 5 km from each headend. The video signal from each scanner is sent through a baseband fiber-optic link to a headend, where it is frequency modulated, multiplexed with other scanner video signals, and distributed over broadband fiber-optic links to monitoring stations. Each receiver consists of a demodulator, a channel selectable tuner, and a video monitor. The current design provides up to 16 scanner channels and 16 remote monitoring station connections. Monitoring stations are placed in 14 clinical locations including the following reading rooms: thoracic, neuro, abdomen, musculoskeletal, gastrointestinal, genitourinary, and pediatric radiology. A radiologist can use any of these 14 monitoring stations to view a patient's CT/MR images in real-time as they appear on any of the six scanner consoles. By selecting the proper channel assigned to a patient's scanner, the radiologist may monitor the examination while using the telephone to communicate with the technologist at the scanner site. This fiber-optic broadband video communication system has been integrated into daily clinical use for over 6 months.

Computer Communication Networks↗

PubMed2001

Usefulness of adding multiplex nested-polymerase chain reaction assay of cerebrospinal fluid samples to routine diagnostic testing for herpesvirus encephalitis.

The present study was conducted to assess the usefulness of adding the multiplex nested-polymerase chain reaction assay of cerebrospinal fluid samples to routine diagnostic testing for herpesvirus encephalitis and to monitor the efficacy of therapy. Cerebrospinal fluid samples from 45 patients with presumed herpesvirus encephalitis were tested for herpes simplex virus, varicella-zoster virus, cytomegalovirus, human herpesvirus 6, and Epstein-Barr virus. Ten of the 45 patients were positive for a virus using the polymerase chain reaction assay: herpes simplex virus (n=5), Epstein-Barr virus (n=3), and herpes simplex virus plus the Epstein-Barr virus (n=2). Cerebrospinal fluid from two patients who had undergone acyclovir therapy gave negative results. Analysis of cerebrospinal fluid by multiplex polymerase chain reaction can be useful for establishing an accurate diagnosis and as a marker of the efficacy of therapy.

Adult↗

PubMed1995

Neuroradiologic findings in fucosidosis, a rare lysosomal storage disease.

Fucosidosis is a rare lysosomal storage disorder with the clinical features of mental retardation, cardiomegaly, dysostosis multiplex, progressive neurologic deterioration, and early death. The neuroradiologic findings in two patients are reported, and include abnormalities within the globus pallidus (both patients) and periventricular white matter (one patient).

Biopsy↗

PubMed2003

Orbital inflammatory pseudotumor due to hypersensitivity vasculitis and mononeuritis multiplex in a patient with atypical, cANCA-positive Wegener's granulomatosis.

OBJECTIVE: We report on a 60-year-old woman with a retro-orbital pseudotumor and polyneuropathy. The retro-orbital inflammation was histologically diagnosed as hypersensitivity vasculitis (HV). As cytoplasmatic antineutrophilic cytoplasmatic antibody (cANCA) and anti-proteinase-3 antibody were detected, the differential diagnosis also included atypical Wegener's granulomatosis. Hypersensitivity vasculitis is defined as small-vessel vasculitis mediated by the deposition of immune complexes (Arthus reaction) after exposure to various agents such as drugs, toxins, and infections. Since an inflammatory retro-orbital pseudotumor due to HV has not previously been reported, the following case is presented. METHODS AND MAIN OUTCOME MEASURES: Magnetic resonance imaging (MRI) revealed retro-orbital infiltrate without granuloma. Histology from an orbital biopsy confirmed HV. Electromyography was used for the diagnosis of polyneuropathy. Serum investigation indicated erythrocyte sedimentation rate (ESR) >100 mm/h, C-reactive protein (CRP) 223 mg/l, antinuclear antibodies 1:80, and cANCA 100 U/ml. RESULTS: The bilateral orbital pseudotumor, polyneuropathy, and serum levels of inflammation reactants (ESR and CRP) improved from therapy with corticosteroids (1 g of methylprednisolone initially) and azathioprine (150 mg/day). CONCLUSIONS: Because of cANCA and anti-proteinase-3 antibody positivity, this case can be viewed more as an atypical Wegener's granulomatosis than a systemic HV. The causal variety of inflammatory orbital pseudotumor, including HV and different therapeutic consequences, requires histological differentiation from usual orbital pseudotumors.

Antibodies, Antineutrophil Cytoplasmic↗

PubMed2002

Multiplexed screening assay for mRNA combining nuclease protection with luminescent array detection.

The principles and performance are described for the ArrayPlate mRNA assay, a multiplexed mRNA assay for high-throughput and high-content screening and drug development. THP-1 monocytes grown and subjected to compound treatments in 96-well plates were subjected to a multiplexed nuclease protection assay in situ. The nuclease protection assay destroyed all cell-derived mRNA, but left intact stoichiometric amounts of 16 target-specific oligonucleotide probes. Upon transfer of processed cell lysates to a microplate that contained a 16-element oligonucleotide array at the bottom of each well, the various probe species were separated by immobilization at predefined elements of the array. Quantitative detection of array-bound probes was by enzyme-mediated chemiluminescence. A high-resolution charge-coupled device imager was used for the simultaneous readout of all 1536 array elements in a 96-well plate. For the measurement of 16 genes in samples of 25000 cells, the average standard deviation from well to well within a plate was 8.6% of signal intensity and was 10.8% from plate to plate. Assay response was linear and reproducibility was constant for all detected genes in samples ranging from 1000 to 50000 cells. When THP-1 monocytes were differentiated with phorbol ester and subsequently activated with bacterial lipopolysaccharide that contained different concentrations of dexamethasone, dose-dependent effects of dexamethasone on the mRNA levels of several genes were observed.

Anti-Inflammatory Agents↗

PubMed2006

[Nano-biocaptures for research and diagnostics in inflammation diseases and cancer].

As part of the ongoing search for ways to decrease the mortality of different pathological conditions related to cancer and inflammatory diseases, nanotechnologies currently under evaluation offer potentially attractive tools for innovative methodologies for early diagnosis, new bioimaging techniques and therapeutic strategies. Nano-tools can be employed for various functions, such as the detection of lesions at very early stages of disease development, extremely precise anatomical localization, or evaluation of the efficacy of medications specifically targeted against cells and pathological tissues. We have synthesized homogeneous CdSe/ZnS (core/shell) highly fluorescent nanocrystals (NC) detectable as individual nanoparticules with a routine fluorescent microscope. These NC are at least 10-fold brighter than the best organic fluorophores and at least 1000-fold more stable against photobleaching than AlexaFluor, for example. When conjugated with proteins, DNA or with drugs, NCs may be excited with the light of any wavelength from UV through visible spectral region providing a range of fluorescence colors depending on their diameter. These properties provide excellent perspectives for high through-put multiplexing and long-term tracking of labeled precursors for days or even weeks. We present here NC applications for ultrasensitive detection of p-glycoprotein, cytokeratins, LCA, Ki67, etc. both on the cellular level and in pathological human surgical specimens.

Cells, Cultured↗

PubMed1997

Cerebrospinal fluid ferritin in HIV infected patients with acute neurological episodes.

OBJECTIVES: To measure cerebrospinal fluid (CSF) ferritin in HIV infected patients with acute neurological episodes and to correlate the findings with the type and severity of neurological disease. METHODS: CSF ferritin and the ratio of CSF to serum albumin (QAlb) were prospectively measured in 27 consecutive HIV infected patients admitted to a specialist unit for investigation of acute neurological episodes; the results were compared with their clinical diagnoses. RESULTS: Ten patients had HIV associated dementia complex, six had cryptococcal meningitis, two had primary CNS lymphoma and nine had miscellaneous conditions including herpes simplex virus encephalitis, cytomegalovirus encephalitis, cerebral toxoplasmosis and mononeuritis multiplex. Overall, 16 (59%) patients had raised CSF ferritin levels, ranging from 13.0 to 50.2 micrograms/l, (median = 16.1 micrograms/l: normal range = 1.0-12.0 micrograms/l). Thirteen of the 16 also had normal QAlb values, implying an intact CSF-blood barrier, and thus that local synthesis of ferritin had occurred. Elevated ferritin levels were not associated with particular neurological diagnoses. In those with HIV associated dementia complex there was no correlation between CSF ferritin levels and the severity of clinical cognitive deficit or the extent of magnetic resonance imaging abnormalities. CONCLUSIONS: An elevated CSF ferritin level is a non-specific finding in HIV infected patients presenting with acute neurological episodes.

AIDS Dementia Complex↗

PubMedDate not supplied

New technologies for the human cytome project.

Cytomes or cell systems are composed of various kinds of single-cells and constitute the elementary building units of organs and organisms. Their individualised (cytomic) analysis overcomes the problem of averaged results from cell and tissue homogenates where molecular changes in low frequency cell populations may be hidden and wrongly interpreted. Analysis of the cytome is of pivotal importance in basic research for the understanding of cells and their interrelations in complex environments like tissues and in predictive medicine where it is a prerequisite for individualised preventive therapy. Analysis of molecular phenotypes requires instrumentation that on the one hand provides high-throughput measurement of individual cells and is on the other hand highly multiplexed, enabling the simultaneous acquisition of many parameters on the single cell level. Upcoming technology suitable to this task, such as slide based cytometry is available or under development. The realisation of cytomic technology is important for the realisation of the human cytome project.

Cell Biology↗

PubMedDate not supplied

Array-based multiplexed screening and quantitation of human cytokines and chemokines.

HydroGel-coated slide is a porous substrate based on a polymer matrix that provides a three-dimensional hydrophilic environment similar to free solution suitable for biomolecular interactions. This substrate has been used to develop fluorescence-based multiplexed cytokine immunoassays. Forty-three monoclonal antibodies (mAb) of cytokines and chemokines were printed at a volume of 350 pL per spot using a Packard BioChip Arrayer. For each probe, four replicates were printed at a pitch of 500 microm in the layout of a 13 x 16 pattern on a 12 x 12 mm2 HydroGel pad. Cytokines and chemokines that are captured by the arrayed mAbs are detected by using another biotinylated mAb, following by the addition of a Texas Red-conjugated streptavidin. The fluorescent images of arrays were recorded using a Packard ScanArray 5000 confocal slide scanner and quantitated using Packard QuantArray software. Experiments demonstrated that 43 cytokines and chemokines could be simultaneously screened and quantitated in conditioned culture media, cell lysates, and human plasma. Using this chip, we have examined cytokine expression in breast cancer cells and identified the chemokines associated with human cervical cancers.

Breast Neoplasms↗

PubMed2026

A Phase I and Biodistribution Study of Ifabotuzumab, a Humanized Agonistic EphA3-Targeted Antibody, in Patients with Recurrent Glioblastoma.

PURPOSE: To conduct a phase I and biodistribution study of the EphA3 antibody ifabotuzumab and zirconium-89-labeled ifabotuzumab (89Zr-ifabotuzumab) in patients with glioblastoma (GBM). PATIENTS AND METHODS: This multisite study was conducted in adults with recurrent GBM whose tumors were measurable according to Response Assessment in Neuro-Oncology (RANO) criteria and whose Eastern Cooperative Oncology Group performance status was 0 to 1. Patients underwent a biodistribution study with PET scans with 89Zr-ifabotuzumab, followed by three infusions of ifabotuzumab at either 3.5 or 5.25 mg/kg before undergoing a second study with 89Zr-ifabotuzumab PET scans. Resected patient diagnostic tumor samples were collected for multiplex immunofluorescence and spatial transcriptomics analyses. RESULTS: Twelve patients were recruited, of which six were treated with 3.5 mg/kg and six with 5.25 mg/kg of ifabotuzumab. 89Zr-ifabotuzumab and associated PET scanning were well tolerated, as was ifabotuzumab. There were no objective responses, but one patient had prolonged stable disease. In addition, two patients showed changes in peritumor edema that were suggestive of modulation of tumor vasculature. 89Zr-ifabotuzumab scans showed highly specific tumor uptake in all patients concordant with disease sites on MRI and PET imaging, without evidence of nonspecific binding. Spatial transcriptomics and immunofluorescence analyses of the patient's archival tissue specimens showed that EphA3 was expressed in the tumor microenvironment in all patients and tumor cells with different transcriptional states. CONCLUSIONS: Targeting EphA3 with ifabotuzumab in patients with GBM is safe and attractive, showing chronologic stable expression across both tumor compartments (particularly in cells with a mesenchymal phenotype) and nontumor compartments (particularly the vascular compartment) with evidence of target modulation.

Humans↗

PubMed2006

Protein chip based miniaturized assay for the simultaneous quantitative monitoring of cancer biomarkers in tissue extracts.

A multiplexed fluorescence immunoassay using a novel planar waveguide technology-based microarray system, ZeptoMARK (Zeptosens), was developed to detect simultaneously urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor-1 (PAI-1), and vascular endothelial growth factor (VEGF) in extracts of breast cancer tissues. The three analytes assay was cross-validated with single-analyte ELISA/chemiluminescence immunosorbent assay tests, revealing good correlations and enhanced assay sensitivities (LODs) of 1 pg/mL for uPA, 33 pg/mL for PAI-1, and 1 pg/mL for VEGF. Values were well within the 80-120% limits for assay recovery and within the +/-20% limits for assay precision. The uPA, PAI-1, and VEGF results obtained from 50 breast cancer cytosols using the protein array system demonstrated that the microarray-based multiplexed assay is a sensitive and robust tool to be used for the simultaneous quantification of cancer markers in small breast cancer tissue samples (core biopsies). The miniaturized, multiplexed assay format has a potential to be used for the quantitative analysis of a larger set of validated markers with significance in disease management.

Biomarkers, Tumor↗

PubMed1997

Mutagenic effects of a single and an exact number of alpha particles in mammalian cells.

One of the main uncertainties in risk estimation for environmental radon exposure using lung cancer data from underground miners is the extrapolation from high- to low-dose exposure where multiple traversal is extremely rare. The biological effects of a single alpha particle are currently unknown. Using the recently available microbeam source at the Radiological Research Accelerator Facility at Columbia University, we examined the frequencies and molecular spectrum of S1- mutants induced in human-hamster hybrid (A(L)) cells by either a single or an exact number of alpha particles. Exponentially growing cells were stained briefly with a nontoxic concentration of Hoechst dye for image analysis, and the location of individual cells was computer-monitored. The nucleus of each cell was irradiated with either 1,2,4, or 8 alpha particles at a linear energy transfer of 90 keV/microm consistent with the energy spectrum of domestic radon exposure. Although single-particle traversal was only slightly cytotoxic to A(L) cells (survival fraction approximately 0.82), it was highly mutagenic, and the induced mutant fraction averaged 110 mutants per 10(5) survivors. In addition, both toxicity and mutant induction were dose-dependent. Multiplex PCR analysis of mutant DNA showed that the proportion of mutants with multilocus deletions increased with the number of particle traversals. These data provide direct evidence that a single a particle traversing a nucleus will have a high probability of resulting in a mutation and highlight the need for radiation protection at low doses.

Alpha Particles↗

PubMed2006

Single-nucleotide polymorphism genotyping by nanoparticle-enhanced surface plasmon resonance imaging measurements of surface ligation reactions.

A sensitive method for the analysis of single nucleotide polymorphisms (SNPs) in genomic DNA that utilizes nanoparticle-enhanced surface plasmon resonance imaging (SPRI) measurements of surface enzymatic ligation reactions on DNA microarrays is demonstrated. SNP identification was achieved by using sequence-specific surface reactions of the enzyme Taq DNA ligase, and the presence of ligation products on the DNA microarray elements was detected using SPRI through the hybridization adsorption of complementary oligonucleotides attached to gold nanoparticles. The use of gold nanoparticles increases the sensitivity of the SPRI so that single bases in oligonucleotides can be successfully identified at a concentration of 1 pM. This sensitivity is amply sufficient for performing multiplexed SNP genotyping by using multiple PCR amplicons and should also allow for the direct detection and identification of SNP sequences from 1 pM unamplified genomic DNA samples with this array-based and label-free SPRI methodology. As a first example of SNP genotyping, three different human genomic DNA samples were screened for a possible point mutation in the BRCA1 gene that is associated with breast cancer.

DNA↗

PubMed2000

Becker muscular dystrophy associated with focal myositis on bone scintigraphy.

METHODS: Bone scintigraphy was performed on a 6-year-old boy with possible sacroiliitis. RESULTS: Extraosseous uptake in the region of the paraspinal, psoas and calf muscles was noted and suggested myositis. Subsequently, his creatine kinase level was found to be elevated. Results of a neuromuscular examination, muscle biopsy with dystrophin immunostaining, and a multiplex polymerase chain reaction led to the diagnosis of Becker muscular dystrophy. CONCLUSIONS: A patient with Becker muscular dystrophy had several distinct areas of myositis localized by bone scintigraphy. Pathologic features including focal myonecrosis and regeneration may contribute to this scintigraphic picture.

Bone and Bones↗

PubMed1998

[The role of the spontaneous occurrence of Pulfrich's stereophenomenon in the diagnosis of demyelinating diseases of the central nervous system].

PURPOSE: Checking the usefulness of the spontaneous occurrence of Pulfrich's stereophenomenon in the diagnosis of demyelinating diseases. MATERIAL AND METHODS: Research embraced 22 patients with visual disturbances (including 9 patients with retrobulbar neuritis and others with anterior ischaemic neuropathy, central retinal vein occlusion, intrabulbar optic neuritis and traumatic atrophy of the optic nerve). The research also embraced 27 patients with demyelinating diseases (sclerosis multiplex). RESULTS: Spontaneous occurrence of Pulfrich's stereophenomenon was reported in 9 retrobulbar neuritis patients. It was also reported in 24 demyelinating patients. CONCLUSION: This simple Pulfrich's pendulum test is positive in 92% of demyelinating patients, including all patients with SM and retrobulbar neuritis.

Demyelinating Diseases↗

PubMedDate not supplied

Arthrogryposis multiplex congenita and cerebellopontine ischemic lesions in sibs: recurrence of prenatal disruptive brain lesions with different patterns of expression?

Arthrogryposis multiplex congenita (AMC) is a heterogeneous group of disorders in which prolonged decrease or absence of fetal movements results in a series of deformational anomalies. The rate of recurrence ranges from 25% in some recessive forms of myogenic arthrogryposis or of primary anterior horn cell loss, to less than 1% in anoxic-ischaemic damage. Cerebral clastic processes are considered as sporadic. We report on a non-consanguineous family in which the first child was affected by AMC and the following pregnancy was terminated because cerebellum hypoplasia was suspected at ultrasound and confirmed by fetal magnetic resonance imaging. Post-mortem findings demonstrated pontocerebellar ischaemic-haemorrhagic injuries. The occurrence of these neurologic abnormalities in the same family suggests a common mechanism, which might correspond to a same genetic defect with different patterns of expression. This is the first prenatal report suggesting that an 'ischaemic' process, usually recognised as sporadic could in fact be due to an inherited abnormality. Careful prenatal follow-up of third-trimester fetal brain development may be required in pregnant women with a family history of AMC.

Adult↗