-
Microcirculation (New York, N.Y. : 1994) Oct 2022The aim of this study was to describe possible remodeling (i.e., dilatation and elongation) of papillary capillaries induced by increased oxygen demand for the repair...
OBJECTIVE
The aim of this study was to describe possible remodeling (i.e., dilatation and elongation) of papillary capillaries induced by increased oxygen demand for the repair process following a skin wound.
METHODS
Computer-assisted video microscopy was used to examine 10 healthy volunteers before (baseline) and after (≈1 h and ≈24 h) an incision (5 mm long and 1 mm deep) on the forearm, 0-1 mm and 30 mm (control site) from the incision. We defined categories from 0 (low) to 3 (high) to grade dilatation and elongation of the nutritive papillary capillaries, as well as the visibility of the superficial vascular plexus. Approximately 10 000 capillaries from 200 films were scored.
RESULTS
The nutritive papillary capillaries were dilated and elongated (p < 0.01) after ≈24 h; that is, elongation (score 1.9 ± 0.9) vs baseline (score 0.9 ± 0.6), p < 0.01 and dilatation (score 2.2 ± 0.7) vs baseline (score 0.3 ± 0.3), p < 0.01. Superficial plexus visibility increased (p < 0.01) after ≈1 h (score 2.0 ± 0.7) and ≈24 h (score 2.7 ± 0.3) vs baseline (score 0.8 ± 0.4).
CONCLUSION
The superficial vascular skin plexus showed enhanced visibility already ≈1 h after the skin trauma. Morphological remodeling in the nutritive papillary capillaries-dilatation and elongation after ≈24 h-facilitate increased O supply.
Topics: Humans; Microcirculation; Capillaries; Skin; Microscopy, Video; Forearm
PubMed: 35231135
DOI: 10.1111/micc.12755 -
Journal of Visualized Experiments : JoVE Feb 2018Here, we demonstrate that lens-free video microscopy enables us to simultaneously capture the kinetics of thousands of cells directly inside the incubator and that it is...
Here, we demonstrate that lens-free video microscopy enables us to simultaneously capture the kinetics of thousands of cells directly inside the incubator and that it is possible to monitor and quantify single cells along several cell cycles. We describe the full protocol used to monitor and quantify a HeLa cell culture for 2.7 days. First, cell culture acquisition is performed with a lens-free video microscope, and then the data is analyzed following a four-step process: multi-wavelength holographic reconstruction, cell-tracking, cell segmentation and cell division detection algorithms. As a result, we show that it is possible to gather a dataset featuring more than 10,000 cell cycle tracks and more than 2 x 10 cell morphological measurements.
Topics: Cell Culture Techniques; Humans; Microscopy, Video
PubMed: 29553497
DOI: 10.3791/56580 -
Scientific Reports Jul 2022Total holographic characterization (THC) is presented here as an efficient, automated, label-free method of accurately identifying cell viability. THC is a...
Total holographic characterization (THC) is presented here as an efficient, automated, label-free method of accurately identifying cell viability. THC is a single-particle characterization technology that determines the size and index of refraction of individual particles using the Lorenz-Mie theory of light scattering. Although assessment of cell viability is a challenge in many applications, including biologics manufacturing, traditional approaches often include unreliable labeling with dyes and/or time consuming methods of manually counting cells. In this work we measured the viability of Saccharomyces cerevisiae yeast in the presence of various concentrations of isopropanol as a function of time. All THC measurements were performed in the native environment of the sample with no dilution or addition of labels. Holographic measurements were made with an in-line holographic microscope using a 40[Formula: see text] objective lens with plane wave illumination. We compared our results with THC to manual counting of living and dead cells as distinguished with trypan blue dye. Our findings demonstrate that THC can effectively distinguish living and dead yeast cells by the index of refraction of individual cells.
Topics: Coloring Agents; Holography; Microscopy; Microscopy, Video; Saccharomyces cerevisiae
PubMed: 35882977
DOI: 10.1038/s41598-022-17098-y -
Physiological Reviews Oct 1999To a certain extent, all cellular, physiological, and pathological phenomena that occur in cells are accompanied by ionic changes. The development of techniques allowing... (Review)
Review
To a certain extent, all cellular, physiological, and pathological phenomena that occur in cells are accompanied by ionic changes. The development of techniques allowing the measurement of such ion activities has contributed substantially to our understanding of normal and abnormal cellular function. Digital video microscopy, confocal laser scanning microscopy, and more recently multiphoton microscopy have allowed the precise spatial analysis of intracellular ion activity at the subcellular level in addition to measurement of its concentration. It is well known that Ca2+ regulates numerous physiological cellular phenomena as a second messenger as well as triggering pathological events such as cell injury and death. A number of methods have been developed to measure intracellular Ca2+. In this review, we summarize the advantages and pitfalls of a variety of Ca2+ indicators used in both optical and nonoptical techniques employed for measuring intracellular Ca2+ concentration.
Topics: Animals; Calcium; Fluorescent Dyes; Humans; Intracellular Fluid; Microscopy, Confocal; Microscopy, Fluorescence; Microscopy, Video
PubMed: 10508230
DOI: 10.1152/physrev.1999.79.4.1089 -
Experimental Eye Research Nov 2022Non-invasive imaging techniques are increasingly used to objectively quantify anterior segment structures of the eye. In this study, we apply the novel oxygen delivery...
Non-invasive imaging techniques are increasingly used to objectively quantify anterior segment structures of the eye. In this study, we apply the novel oxygen delivery index (ODIN) concept that, quantifies microvascular capacity for oxygen delivery, to the ocular surface in healthy humans. The purpose of the study was to test the applicability of the technologies used for data acquisition from the human ocular surface. We also validated whether the ODIN concept has sufficient sensitivity to detect and differentiate between microvascular structure and function in limbal and bulbar conjunctiva. Multiple ocular surface measurements using computer-assisted video microscopy (field of view: 1.6 mm × 0.9 mm) and diffuse reflectance spectroscopy (measuring volume: ∼0.1 mm3) were obtained from limbal and bulbar conjunctiva in 20 healthy volunteers. Three parameters were extracted during analyses: Functional capillary density, capillary flow velocity, and microvascular oxygen saturation. Functional capillary density was higher at limbus than in bulbar conjunctiva (11.2 ± 1.8 c/mm versus 5.2 ± 1.2 c/mm, p < 0.01), and microvascular oxygen saturation was lower at limbus (77 ± 8%) as compared to bulbar conjunctiva (89 ± 6%), p < 0.01. More than 80% of scored capillaries had continuous blood flow and no difference was seen between the recording sites (p = 0.68). In conclusion, the ODIN concept is applicable for the assessment of human ocular surface microvascular function and has sufficient sensitivity to detect increased capillary density and oxygen extraction at limbus as compared with bulbar conjunctiva.
Topics: Humans; Microcirculation; Microscopy, Video; Conjunctiva; Spectrum Analysis; Oxygen; Computers
PubMed: 36055389
DOI: 10.1016/j.exer.2022.109232 -
Experimental Eye Research Dec 2020In piglets we tested the applicability of digital video microscopy and diffuse reflectance spectroscopy for non-invasive assessments of limbal and bulbar conjunctival...
In piglets we tested the applicability of digital video microscopy and diffuse reflectance spectroscopy for non-invasive assessments of limbal and bulbar conjunctival microcirculation. A priori we postulated that the metabolic rate is higher in limbal as compared to bulbar conjunctiva, and that this difference is reflected in microvascular structure or function between the two locations. Two study sites, Oslo University Hospital (OUH), Norway and Cleveland Clinic (CC), USA, used the same video microscopy and spectroscopy techniques to record limbal and bulbar microcirculation in sleeping piglets. Recordings were analyzed with custom-made software to quantify functional capillary density, capillary flow velocity and microvascular oxygen saturation in measuring volumes of approximately 0.1 mm. The functional capillary density was higher in limbus than in bulbar conjunctiva at both study sites (OUH: 18.1 ± 2.9 versus 12.2 ± 2.9 crossings per mm line, p < 0.01; CC: 11.3 ± 3.0 versus 7.1 ± 2.8 crossings per mm line, p < 0.01). Median categorial capillary blood flow velocity was higher in bulbar as compared with limbal recordings (CC: 3 (1-3) versus 1 (0-3), p < 0.01). Conjunctival microvascular oxygen saturation was 88 ± 5.9% in OUH versus 94 ± 7.5% in CC piglets. Non-invasive digital video microscopy and diffuse reflectance spectroscopy can be used to obtain data from conjunctival microcirculation in piglets. Limbal conjunctival microcirculation has a larger capacity for oxygen delivery as compared with bulbar conjunctiva.
Topics: Animals; Blood Flow Velocity; Conjunctiva; Female; Image Processing, Computer-Assisted; Male; Microcirculation; Microscopy, Video; Microvessels; Models, Anatomic; Models, Animal; Spectrum Analysis; Swine
PubMed: 33157128
DOI: 10.1016/j.exer.2020.108312 -
The Journal of the Acoustical Society... Jul 2019Ultra-high-speed video microscopy and numerical modeling were used to assess the dynamics of microbubbles at the surface of urinary stones. Lipid-shell microbubbles...
Ultra-high-speed video microscopy and numerical modeling were used to assess the dynamics of microbubbles at the surface of urinary stones. Lipid-shell microbubbles designed to accumulate on stone surfaces were driven by bursts of ultrasound in the sub-MHz range with pressure amplitudes on the order of 1 MPa. Microbubbles were observed to undergo repeated cycles of expansion and violent collapse. At maximum expansion, the microbubbles' cross-section resembled an ellipse truncated by the stone. Approximating the bubble shape as an oblate spheroid, this study modeled the collapse by solving the multicomponent Euler equations with a two-dimensional-axisymmetric code with adaptive mesh refinement for fine resolution of the gas-liquid interface. Modeled bubble collapse and high-speed video microscopy showed a distinctive circumferential pinching during the collapse. In the numerical model, this pinching was associated with bidirectional microjetting normal to the rigid surface and toroidal collapse of the bubble. Modeled pressure spikes had amplitudes two-to-three orders of magnitude greater than that of the driving wave. Micro-computed tomography was used to study surface erosion and formation of microcracks from the action of microbubbles. This study suggests that engineered microbubbles enable stone-treatment modalities with driving pressures significantly lower than those required without the microbubbles.
Topics: Acoustics; Computer Simulation; Contrast Media; Elasticity; Microbubbles; Microscopy, Video; Models, Biological; Urinary Calculi
PubMed: 31370610
DOI: 10.1121/1.5116693 -
HPB : the Official Journal of the... Oct 2011The use of loupe magnification during complex hepatobiliary and pancreatic (HBP) surgery has become routine. Unfortunately, loupe magnification has several disadvantages...
BACKGROUND
The use of loupe magnification during complex hepatobiliary and pancreatic (HBP) surgery has become routine. Unfortunately, loupe magnification has several disadvantages including limited magnification, a fixed field and non-variable magnification parameters. The aim of this report is to describe a simple system of video-microscopy for use in open surgery as an alternative to loupe magnification.
METHODS
In video-microscopy, the operative field is displayed on a TV monitor using a high-definition (HD) camera with a special optic mounted on an adjustable mechanical arm. The set-up and application of this system are described and illustrated using examples drawn from pancreaticoduodenectomy, bile duct repair and liver transplantation.
RESULTS
This system is easy to use and can provide variable magnification of ×4-12 at a camera distance of 25-35 cm from the operative field and a depth of field of 15 mm. This system allows the surgeon and assistant to work from a HD TV screen during critical phases of microsurgery.
CONCLUSIONS
The system described here provides better magnification than loupe lenses and thus may be beneficial during complex HPB procedures. Other benefits of this system include the fact that its use decreases neck strain and postural fatigue in the surgeon and it can be used as a tool for documentation and teaching.
Topics: Biliary Tract Surgical Procedures; Equipment Design; Humans; Image Enhancement; Liver Transplantation; Microscopy, Video; Microsurgery; Pancreaticoduodenectomy; Treatment Outcome
PubMed: 21929677
DOI: 10.1111/j.1477-2574.2011.00361.x -
Journal of Dairy Science Feb 2018The objective of this study was to apply digital imaging to improve quantification of rumen protozoal biomass and distinguish treatment differences in cell motility and...
The objective of this study was to apply digital imaging to improve quantification of rumen protozoal biomass and distinguish treatment differences in cell motility and volume among ruminal protozoa. Observations of protozoa in rumen fluid treated with essential oils (CinnaGar, CIN; Provimi North America, Brookville, OH) or an ionophore (monensin, MON) indicated possible cell shrinkage. We hypothesized that MON would decrease protozoal motility and interact with CIN on cell volume. In addition, we hypothesized that analysis of still frames from video of swimming protozoa would improve volume prediction accuracy. Flocculated rumen fluid was incubated in batch culture dosed with N-free feed only (control), MON, CIN, or a combination of MON+CIN. Samples were taken at 0, 3, or 6 h post-treatment and wet-mounted on a microscope fitted with a high-definition camera. At 3 h post-inoculation, there was a treatment interaction for average speed such that CIN attenuated the effect of MON, with treatment means of 243, 138, 211, and 183 µm/s for control, MON, CIN, and MON+CIN, respectively. At 6 h post-inoculation, MON decreased average speed by 79.2 µm/s compared with the main effect mean without MON. We measured both minimum and maximum diameters (depth and width, respectively) perpendicular to the longitudinal axis of swimming protozoa, yielding a 3-dimensional estimate of protozoal volume. The ellipsoid formula (4/3)πabc, where a = 1/2 length, b = 1/2 width, and c = 1/2 depth, was compared with previously published volume estimations using genera-specific coefficients (genera-specific coefficient × length × width). Residuals (genera-specific coefficients - ellipsoid) were plotted against predicted (ellipsoid) and centered to the mean (X-x¯) to evaluate both mean and slope biases. For Entodinium spp., Y = 0.248 (±0.037) (X - 7.98 × 10) + 1.97 × 10 (±1.48 × 10); n = 100; r [coefficient of determination (squared correlation coefficient)] = 0.31, with significant slope and mean biases. For family Isotrichidae, Y = -0.124 (±0.068) (X - 2.54 × 10) - 1.21 × 10 (±4.86 × 10); n = 32; r = 0.10, where slope tended to be different from zero but with no mean bias. For Epidinium spp., Y = 0.375 (±0.056) (X - 2.45 × 10) + 6.65 × 10 (±0.28 × 10); n = 64; r = 0.43, with both mean and slope biases. The present regression analyses demonstrate that the genera-specific coefficient-based method more likely overestimates volume for Entodinium and Epidinium than for the teardrop-shaped Isotrichidae. Based on simulations derived from previous literature reporting treatments that depress protozoal populations or among-animal changes in protozoal population structures, our proposed ellipsoid method offers potential to advance the prediction of treatment effects on protozoal volume and to shift focus from the number of cells present to the diversity, function, and biomass of protozoa under various treatment conditions.
Topics: Animals; Antiprotozoal Agents; Cattle; Cattle Diseases; Cell Size; Ciliophora; Ciliophora Infections; Hydrogen-Ion Concentration; Microscopy, Video; Monensin; North America; Rumen
PubMed: 29174145
DOI: 10.3168/jds.2017-13513 -
Immunity Sep 2004Recent advances in photonics, particularly multi-photon microscopy (MPM) and new molecular and genetic tools are empowering immunologists to answer longstanding... (Review)
Review
Recent advances in photonics, particularly multi-photon microscopy (MPM) and new molecular and genetic tools are empowering immunologists to answer longstanding unresolved questions in living animals. Using intravital microscopy (IVM) investigators are dissecting the cellular and molecular underpinnings controlling immune cell motility and interactions in tissues. Recent IVM work showed that T cell responses to antigen in lymph nodes are different from those observed in vitro and appear dictated by factors uniquely relevant to intact organs. Other IVM models, particularly in the bone marrow, reveal how different anatomic contexts regulate leukocyte development, immunity, and inflammation. This article will discuss the current state of the field and outline how IVM can generate new discoveries and serve as a "reality check" for areas of research that were formerly the exclusive domain of in vitro experimentation.
Topics: Animals; Cell Communication; Cell Movement; Dendritic Cells; Diagnostic Imaging; Humans; Image Processing, Computer-Assisted; Microscopy; Microscopy, Video; Models, Immunological; T-Lymphocytes
PubMed: 15357943
DOI: 10.1016/j.immuni.2004.08.006