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1.
Nanoscale ; 15(28): 12124, 2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37435809

ABSTRACT

Correction for 'Label free localization of nanoparticles in live cancer cells using spectroscopic microscopy' by Graham L. C. Spicer et al., Nanoscale, 2018, 10, 19125-19130, https://doi.org/10.1039/C8NR07481J.

2.
J Opt Soc Am A Opt Image Sci Vis ; 39(4): 711-725, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-35471398

ABSTRACT

The mirror tunnel is a component used to extend the depth of focus for compact imaging probes used in endoscopic optical coherence tomography (OCT). A fast and accurate method for mirror tunnel probe simulation, characterization, and optimization is needed, with the aim of reconciling wave- and ray-optics simulation methods and providing a thorough description of the physical operating principle of the mirror tunnel. BeamLab software, employing the beam propagation method, was used to explore the parameter space and quantify lateral resolution and depth of focus extension. The lateral resolution performance was found to depend heavily on the metric chosen, implying that care should be taken in the interpretation of optimization and simulation results. Interpreting the mirror tunnel exit face as an extended object gives an understanding of the probe operation, decoupling it from the focusing optics and potentially helping to reduce the parameter space for future optimization.


Subject(s)
Lenses , Tomography, Optical Coherence , Endoscopy , Equipment Design , Optics and Photonics , Tomography, Optical Coherence/methods
3.
Nanoscale ; 10(40): 19125-19130, 2018 Oct 18.
Article in English | MEDLINE | ID: mdl-30298892

ABSTRACT

Gold nanoparticles (GNPs) have become essential tools used in nanobiotechnology due to their tunable plasmonic properties and low toxicity in biological samples. Among the available approaches for imaging GNPs internalized by cells, hyperspectral techniques stand out due to their ability to simultaneously image and perform spectral analysis of GNPs. Here, we present a study utilizing a recently introduced hyperspectral imaging technique, live-cell PWS, for the imaging, tracking, and spectral analysis of GNPs in live cancer cells. Using principal components analysis, the extracellular or intracellular localization of the GNPs can be determined without the use of exogenous labels. This technique uses wide-field white light, assuring minimal toxicity and suitable signal-to-noise ratio for spectral and temporal resolution of backscattered signal from GNPs and local cellular structures. The application of live-cell PWS introduced here could make a great impact in nanomedicine and nanotechnology by giving new insights into GNP internalization and intracellular trafficking.


Subject(s)
Gold , Materials Testing , Metal Nanoparticles/chemistry , Neoplasms/diagnostic imaging , Gold/chemistry , Gold/pharmacology , HeLa Cells , Humans , Neoplasms/metabolism
4.
Phys Med Biol ; 61(19): 6892-6904, 2016 10 07.
Article in English | MEDLINE | ID: mdl-27618507

ABSTRACT

In cancer biology, there has been a recent effort to understand tumor formation in the context of the tissue microenvironment. In particular, recent progress has explored the mechanisms behind how changes in the cell-extracellular matrix ensemble influence progression of the disease. The extensive use of in vitro tissue culture models in simulant matrix has proven effective at studying such interactions, but modalities for non-invasively quantifying aspects of these systems are scant. We present the novel application of an imaging technique, Inverse Spectroscopic Optical Coherence Tomography, for the non-destructive measurement of in vitro biological samples during matrix remodeling. Our findings indicate that the nanoscale-sensitive mass density correlation shape factor D of cancer cells increases in response to a more crosslinked matrix. We present a facile technique for the non-invasive, quantitative study of the micro- and nano-scale structure of the extracellular matrix and its host cells.


Subject(s)
Cell Proliferation , Collagen/metabolism , Colonic Neoplasms/pathology , Cross-Linking Reagents/metabolism , Extracellular Matrix/pathology , Tomography, Optical Coherence/methods , Colonic Neoplasms/metabolism , Extracellular Matrix/metabolism , Humans , Tumor Cells, Cultured
5.
J Insect Sci ; 11: 19, 2011.
Article in English | MEDLINE | ID: mdl-21526930

ABSTRACT

Natural enemies of the imported fire ants, Solenopsis invicta Buren S. richteri Forel (Hymenoptera: Formicidae), and their hybrid, include a suite of more than 20 fire ant decapitating phorid flies from South America in the genus Pseudacteon. Over the past 12 years, many researchers and associates have cooperated in introducing several species as classical or self-sustaining biological control agents in the United States. As a result, two species of flies, Pseudacteon tricuspis Borgmeier and P. curvatus Borgmeier (Diptera: Phoridae), are well established across large areas of the southeastern United States. Whereas many researchers have published local and state information about the establishment and spread of these flies, here distribution data from both published and unpublished sources has been compiled for the entire United States with the goal of presenting confirmed and probable distributions as of the fall of 2008. Documented rates of expansion were also used to predict the distribution of these flies three years later in the fall of 2011. In the fall of 2008, eleven years after the first successful release, we estimate that P. tricuspis covered about 50% of the fire ant quarantined area and that it will occur in almost 65% of the quarantine area by 2011. Complete coverage of the fire ant quarantined area will be delayed or limited by this species' slow rate of spread and frequent failure to establish in more northerly portions of the fire ant range and also, perhaps, by its preference for red imported fire ants (S. invicta). Eight years after the first successful release of P. curvatus, two biotypes of this species (one biotype occurring predominantly in the black and hybrid imported fire ants and the other occurring in red imported fire ants) covered almost 60% of the fire ant quarantined area. We estimate these two biotypes will cover almost 90% of the quarantine area by 2011 and 100% by 2012 or 2013. Strategic selection of several distributional gaps for future releases will accelerate complete coverage of quarantine areas. However, some gaps may be best used for the release of additional species of decapitating flies because establishment rates may be higher in areas without competing species.


Subject(s)
Ants , Demography , Diptera/physiology , Insect Control/methods , Predatory Behavior/physiology , Animals , Population Dynamics , Southeastern United States
6.
J Econ Entomol ; 104(6): 2009-16, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22299364

ABSTRACT

Insecticides are widely used to manage turfgrass pest such as white grubs (Coleoptera: Scarabaeidae). Red imported fire ants, Solenopsis invicta (Buren) are important predators and pests in managed turfgrass. We tested the susceptibility of white grub life stages (adults, egg, and larvae) to predation by S. invicta and determined if insecticides applied for control of S. invicta would result in locally greater white grub populations. Field trials over 2 yr evaluated bifenthrin, fipronil, and hydramethylnon applied to large and small scale turfgrass plots for impacts on fire ant foraging and white grub populations. Coincident with these trials, adults, larvae, and eggs of common scarab species were evaluated for susceptibility to predation by S. invicta under field conditions. Field trials with insecticides failed to show a significant increase in white grub populations resulting from treatment of turfgrass for fire ants. This, in part, may be because of a lack of predation of S. invicta on adult and larval scarabs. Egg predation was greatest at 70% but < 20% of adults and larvae were attacked in a 24 h test. Contrary to other studies, results presented here suggest that fire ants and fire ant control products applied to turfgrass have a minimal impact on white grub populations.


Subject(s)
Ants/physiology , Coleoptera/drug effects , Insecticides/toxicity , Predatory Behavior , Pyrazoles/toxicity , Pyrethrins/toxicity , Pyrimidinones/toxicity , Alabama , Animals , Coleoptera/physiology , Cynodon , Female , Larva/drug effects , Larva/physiology , Male , Ovum/drug effects , Ovum/physiology , Population Density , Seasons , Species Specificity
7.
J Invertebr Pathol ; 96(1): 18-27, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17412359

ABSTRACT

Studies were conducted to examine the phenology, geographic distribution, and host specificity of the Solenopsis invicta virus-1 (SINV-1). Two genotypes examined, SINV-1 and -1A, exhibited similar seasonal prevalence patterns. Infection rates among colonies of S. invicta in Gainesville, Florida, were lowest from early winter (December) to early spring (April) increasing rapidly in late spring (May) and remaining high through August before declining again in the fall (September/October). Correlation analysis revealed a significant relationship between mean monthly temperature and SINV-1 (p<0.0005, r=0.82) and SINV-1A (p<0.0001, r=0.86) infection rates in S. invicta colonies. SINV-1 was widely distributed among S. invicta populations. The virus was detected in S. invicta from Argentina and from all U.S. states examined, with the exception of New Mexico. SINV-1 and -1A were also detected in other Solenopsis species. SINV-1 was detected in Solenopsis richteri and the S. invicta/richteri hybrid collected from northern Alabama and Solenopsis geminata from Florida. SINV-1A was detected in S. geminata and Solenopsis carolinensis in Florida and the S. invicta/richteri hybrid in Alabama. Of the 1989 arthropods collected from 6 pitfall trap experiments from Gainesville and Williston, Florida, none except S. invicta tested positive for SINV-1 or SINV-1A. SINV-1 did not appear to infect or replicate within Sf9 or Dm-2 cells in vitro. The number of SINV-1 genome copies did not significantly increase over the course of the experiment, nor were any cytopathic effects observed. Phylogenetic analyses of SINV-1/-1A nucleotide sequences indicated significant divergence between viruses collected from Argentina and the U.S.


Subject(s)
Ants/virology , Genome, Viral , Host-Parasite Interactions/physiology , Picornaviridae Infections/epidemiology , Picornaviridae/genetics , Amino Acid Sequence , Animals , Molecular Sequence Data , Phylogeny , Picornaviridae Infections/veterinary , Reverse Transcriptase Polymerase Chain Reaction
8.
Gen Comp Endocrinol ; 148(2): 105-15, 2006 Sep 01.
Article in English | MEDLINE | ID: mdl-16430894

ABSTRACT

The literature on the ontogeny and phylogeny of the endocrine pancreas of ray-finned fishes is summarized since the latest review in fish [Youson, J.H., Al-Mahrouki, A.A., 1999. Review. Ontogenetic and phylogenetic development of the endocrine pancreas (islet organ) in fishes. Gen. Comp. Endocrinol. 116, 303-335]. A basic description and a demonstration of the diversity of the fish islet organ is provided through new immunohistochemical data on islet tissue from a basal teleost, an osteoglossomorph, and a more derived teleost, a perciforme. Unlike the previous review, the present report provides a review and discussion of the utility of sequence data of insulin, somatostatin, and NPY- and glucagon-family peptides in phylogenetic analyses of jawed and jawless fishes. The present study also provides the first comparative analysis of sequences of preprohormones of endocrine peptides from closely related basal teleost species. Some nucleotide and deduced amino acid sequence data for preprosomatostatins (PPSS-I and/or -II) are compared for four species of bonytongues, Osteoglossomorpha, and with PPSSs of the white sucker, Catostomus commersoni, representing Cypriniformes, a more generalized teleost order. Phylogenetic analysis of deduced amino acid sequences of the PPSSs of these species and others from databases indicates good support for the monophyly of Osteoglossomorpha and some support for the present taxonomic grouping of the osteoglossomorphs examined, and also the white sucker. However, PPSS may have limited phylogenetic utility due to the relative short sequence, particularly in resolving relationships among lineages that diverged over a short period of time. Since in the few fish species examined we have just touched the surface in describing the diversity of structure of the islet organ, and likely the nature of the products of its cells, this report promotes the continued study of this organ.


Subject(s)
Fishes/embryology , Fishes/genetics , Fishes/physiology , Islets of Langerhans/embryology , Islets of Langerhans/physiology , Amino Acid Sequence , Animals , Cypriniformes/genetics , Islets of Langerhans/anatomy & histology , Molecular Sequence Data , Pancreatic Polypeptide/genetics , Perciformes/genetics , Phylogeny , Sequence Homology, Amino Acid , Somatostatin/genetics
9.
J Adolesc Health ; 29(4): 267-70, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11587910

ABSTRACT

OVERVIEW: Patients with anorexia nervosa have functional cardiac abnormalities secondary to their nutritionally depleted state. These abnormalities include decreased left ventricular (LV) mass and varying degrees of LV systolic dysfunction. Assessment of LV diastolic function and quantitative assessment of right ventricular function are not routinely performed. The myocardial performance index (MPI) is a relatively new, simple, quantitative measure of global myocardial function. The purpose of this study was to evaluate left and right ventricular function in 13 patients with anorexia nervosa with the MPI and compare it to more commonly used echocardiographic measures of ventricular function.


Subject(s)
Anorexia Nervosa/complications , Heart Diseases/diagnostic imaging , Heart Diseases/physiopathology , Ventricular Function/physiology , Adolescent , Echocardiography, Doppler , Electrocardiography , Female , Heart Function Tests , Humans , Male , Retrospective Studies , Time Factors
10.
Mol Cell Endocrinol ; 174(1-2): 51-8, 2001 Mar 28.
Article in English | MEDLINE | ID: mdl-11306171

ABSTRACT

Several preproinsulin cDNAs were isolated and characterized from four members of the Osteoglossomorpha (an ancient teleost group); Osteoglossum bicirrhosum (arawana), Pantodon buchholzi (butterfly fish), Notopterus chitala (feather fin knife fish), Hiodon alosoides (goldeye) and Gnathonemus petersii (elephantnose). In addition, we isolated and characterized the preproinsulin cDNA from Catostomus commersoni (white sucker, as a representative of a generalized teleost). The comparative analysis of the sequences revealed conservation of the cystine residues known to be involved in the formation of the disulfide bridges, as well as residues involved in the hexamer formation, except for B-17 in the butterfly fish, the arawana and the goldeye. However, the N-terminus of the B-chain was very weakly conserved among the species studied. Residues known to be significant for maintaining receptor-binding conformation and those known to comprise the receptor-binding domain were all conserved, except for a conservative substitution at B13, aspartate substituted glutamate in the arawana, goldeye, butterfly fish and white sucker, and at B16, phenylalanine substituted tyrosine in the elephantnose. Phylogenetic analysis of the sequences revealed a monophyletic grouping of the osteoglossomorphs, and showed that they were not the most basal living teleost. Comparative sequence analysis of preproinsulins among the osteoglossomorphs was useful in assessment of intergroup relationship, relating elephantnose with the feather fin knife fish and the arawana, butterfly fish, and goldeye. This arrangement of species is consistent with relationships based on other more classical parameters, except for the goldeye which was assessed as being sister to all the osteoglossomorphs. The white sucker was grouped with the common carp and both are cyprinids.


Subject(s)
DNA, Complementary/genetics , Fishes/genetics , Proinsulin/genetics , Protein Precursors/genetics , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , Conserved Sequence , Cyprinidae/genetics , Insulin , Molecular Sequence Data , Pancrelipase , Phylogeny , RNA/genetics , RNA/isolation & purification , Sequence Alignment , Sequence Analysis , Vertebrates/genetics
11.
Catheter Cardiovasc Interv ; 51(1): 61-4, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10973021

ABSTRACT

This article describes our initial experience with the P.D. Access Doppler needle for obtaining vascular access in pediatric patients. Patients were considered for use of the P.D. Access Doppler needle (Escalon Vascular Access, New Berlin, WI) if they had a history of difficult access or body habitus limitations to vascular access. An 18-, a 20-, or a 22-gauge bare needle with an inserted Doppler stylet was utilized. The time from initial subcutaneous entry of the Doppler needle until wire placement into the vessel lumen was recorded. Initial attempts to cannulate were performed with standard Seldinger technique. If attempts with the standard technique were unsuccessful, then P.D. Access was utilized. However, P.D. Access was used primarily in small children for internal jugular vein cannulation or in patients with coarctation who had absent/diminished femoral pulses. P.D. Access cannulation was attempted 39 times (31 patients). Median age is 23 months (range, 1 day to 15 years). Median weight is 10.5 kg (range, 1.7-57 kg). These patients had a mean of two prior cardiac catheterizations and/or surgeries (range, 0-6 procedures). Use of P.D. Access resulted in successful cannulation in 35/39 (90%) attempts. In successful outcomes, the time from initial subcutaneous entry to cannulation is 6.5+/-4.9 min. In unsuccessful outcomes, failure was due to prior hematoma formation, operator inexperience, or prior vessel occlusion. Successful use of P.D. Access shortens the duration of vascular access in difficult pediatric patients. In our cardiac catheterization laboratory, this technique has become the preferred initial entry technique for cannulation of the internal jugular vein in small children. In addition, this technique was particularly useful for femoral artery cannulation in patients with coarctation of the aorta with absent/diminished femoral pulses.


Subject(s)
Cardiac Catheterization/instrumentation , Cardiac Catheterization/methods , Needles , Pediatrics/instrumentation , Pediatrics/methods , Ultrasonography, Doppler/instrumentation , Adolescent , Cardiac Catheterization/adverse effects , Child , Child, Preschool , Equipment Design , Heart Defects, Congenital/diagnosis , Hematoma/etiology , Humans , Infant , Infant, Newborn , Treatment Failure , Treatment Outcome
12.
Ann Thorac Surg ; 67(2): 528-31, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10197683

ABSTRACT

BACKGROUND: Treatment of hypoplasia of the entire arch in coarctation is a surgical challenge. The current approaches have technical difficulties, high recurrence rates, and increased morbidity and mortality. METHODS: Over a 14-month period, a combined extended end-to-end repair with patch enlargement of the concavity of the entire arch was performed in 6 neonates and 1 infant. Through a midsternotomy and using cardiopulmonary bypass and hypothermia, extended end-to-end repair was performed initially leaving the proximal anastomosis open. The enlarging polytetrafluoroethylene patch was then sutured starting at the incised descending aorta distal to the extended end-to-end repair and continued retrogradely through the transverse arch to the ascending aorta proximal to the aortic cannulation site. One neonate had a patent ductus arteriosus and another had ventricular septal defect closure. One neonate had arterial switch and 3 had Norwood-type procedures performed with the enlarging patch extended to the pulmonary artery anastomosis. The remaining infant had arch enlargement performed after an arterial switch procedure and extended end-to-end repair. RESULTS: All patients did well and showed no residual gradient up to 1 year follow-up. Two patients successfully had bidirectional Glenn shunt at 9 months of age, and one had closure of residual arterial septal defect at 8 months of age. CONCLUSION: The combined extended end-to-end repair and arch enlargement procedure should minimize recurrence rates because of a tension-free enlargement of the entire aortic arch and elimination of the coarctation ridge and ductile tissues. Combined with the arterial switch and Norwood-type procedures, the approach results in a large neoaorta.


Subject(s)
Anastomosis, Surgical , Aortic Coarctation/surgery , Aorta, Thoracic/surgery , Aortic Coarctation/diagnosis , Aortography , Blood Vessel Prosthesis Implantation , Echocardiography , Female , Follow-Up Studies , Heart Defects, Congenital/diagnosis , Heart Defects, Congenital/surgery , Humans , Infant , Infant, Newborn , Male , Polytetrafluoroethylene , Suture Techniques , Treatment Outcome
13.
J Adolesc Health ; 24(3): 160-2, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10195798

ABSTRACT

PURPOSE: The frequency and safety of ear piercing and tattooing were assessed in a group of children, adolescents, and adults with congenital heart disease (CHD). Also, a group of physicians who care for adolescents and adults with CHD were surveyed for opinions and experiences regarding piercing and tattooing. METHODS: An eight-question survey was mailed to 445 patients (181 adults and 264 children) from one center. A different five-question survey was mailed to 176 physician members of the International Society of Adult Congenital Cardiac Disease. RESULTS: The patient survey was completed by 152 of 445 (34%) patients (mean age +/- standard deviation 19.8 +/- 16.2 years; range 0.25-67 years). Eighty-eight of 152 (58%) patients were female. Ear piercing occurred in 65 of 152 (43%) patients (mean age 12.4 +/- 8.7 years; range 0.25-45 years). Prior to piercing, only 4 of 65 (6%) patients took antibiotics, but 15 of 65 (23%) had piercing-related infections. No patient had endocarditis. Infections occurred 1 week to 3 years after piercing. All were local skin infections. Tattoos were placed in 8 of 152 (5%) patients (median age 17.5 years; range 13-56 years). No antibiotic use or infections were reported in patients with tattoos. The physician survey was completed by 118 of 176 (67%) physicians. The majority of physicians did not approve of patients having piercing or tattooing performed. However, 60% of physicians believed that antibiotic prophylaxis is indicated for these procedures. CONCLUSIONS: Despite the opinion of many physicians, most patients do not take antibiotic prophylaxis for piercing and tattooing. Patients apparently do not suffer serious sequelae. The efficacy of standard antibiotic regimes as applied to ear piercing and tattooing requires further study, since these procedures are increasingly popular in modern society.


Subject(s)
Antibiotic Prophylaxis/statistics & numerical data , Attitude of Health Personnel , Cosmetic Techniques/adverse effects , Ear, External , Heart Defects, Congenital , Infections/etiology , Tattooing/adverse effects , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Punctures/adverse effects , Risk Factors , Surveys and Questionnaires
15.
Am J Cardiol ; 79(9): 1281-2, 1997 May 01.
Article in English | MEDLINE | ID: mdl-9164907

ABSTRACT

Transaxillary muscle-sparing patent ductus arteriosus closure performed as same-day surgery is described in 10 patients. This approach provides a superb cosmetic result while obviating the need for thoracostomy tube placement.


Subject(s)
Ductus Arteriosus, Patent/economics , Ductus Arteriosus, Patent/surgery , Adolescent , Child , Child, Preschool , Cost-Benefit Analysis , Follow-Up Studies , Humans , Infant , Infant, Newborn , Length of Stay/economics , Thoracotomy/economics
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