Inducing Genetic Change in Cancer Cells Using Lasers
Inducing Genetic Change in Cancer Cells Using Lasers

Author: Muhammad Waleed

Publisher: LAP Lambert Academic Publishing

Published: 2014-12-04

Total Pages: 56

ISBN-13: 9783659646485

DOWNLOAD EBOOK

In this book, we demonstrate a new single cell optoporation and transfection technique using femtosecond Gaussian laser beam and optical tweezers. Tightly focused near-infrared (NIR) femtosecond laser pulse was employed to transiently perforate the cellular membrane at a single point of MCF-7 cancer cell. A distinct technique is developed by trapping the microparticle using optical tweezers to focus femtosecond laser exactly on the cell membrane to puncture it for the desired time. Subsequently, calculated amount of external gene was introduced in the cell by trapping and inserting same plasmid coated microparticle into optoporated cell using optical tweezers. Various experimental parameters such as femtosecond laser exposure power, exposure time, punctured hole size, exact focusing of femtosecond laser and cell healing time were closely analyzed to optimize the best conditions for cell viability. Trapped particle position is detected by another co aligned continuous wave laser. In the end, after insertion of plasmid coated microparticle, the targeted cells exhibited green fluorescent protein (GFP) under the fluorescent microscope hence confirming successful genetic change.

Laser Manipulation of Cells and Tissues
Laser Manipulation of Cells and Tissues

Author: Michael W. Berns

Publisher: Academic Press

Published: 2007-06-20

Total Pages: 824

ISBN-13:

DOWNLOAD EBOOK

The use of laser-based manipulation tools has literally exploded on the cell biology and molecular pathology scene, resulting in as many different laser micromanipulation systems as there are people using them. Laser Manipulation of Cells and Tissues ties all these systems and studies together, describing all of the different kinds of research and practical/analytical applications of laser manipulation. It also provides the reader with the basic information needed to actually build one's own laser micro-manipulation system. The combination of imaging and molecular probe technology with laser micromanipulation greatly extends the use of this technology in molecular, cellular, developmental and patho-biology/medicine. This book should be valuable to scientists, clinicians, and students in the fields of cell and developmental biology, cell physiology, cancer biology, pathology, and stem cell biology. Devotes four chapters to laser catapulting and capture of DNA and other cellular material for biochemical analysis - a major use of this technology that has been adapted for molecular pathology both in clinical medicine and research Discusses the theory of laser tweezers (optical tweezers) and its application to novel problems in biology Covers topics on optoporation (getting things into cells), uncaging of molecules, and the ability to collect and analyze nanomolar amounts of cell material by an array of biochemical/physical tools of particular interest to cell biologists and drug discovery researchers

Near Infrared, High Energy, Ultrashort Pulse Laser-Light Exposure Genetically Induces P53, a Gene in the DNA Repair and Cell Suicide Pathways in Cultured Human Cells
Near Infrared, High Energy, Ultrashort Pulse Laser-Light Exposure Genetically Induces P53, a Gene in the DNA Repair and Cell Suicide Pathways in Cultured Human Cells

Author:

Publisher:

Published: 1999

Total Pages: 13

ISBN-13:

DOWNLOAD EBOOK

The use of laser light for targeting devices and weapons has sharply increased the likelihood that aircrew and support personnel will be exposed to laser light during operations. The increased potential for exposure of humans highlights the need for scientifically-based safety standards for laser exposure at the ultrashort pulse lengths. Current safety standards are largely extrapolations of exposure limits at longer pulse lengths using a minimal visible lesion endpoint in the Rhesus monkey retinal model. A non-animal model for assessing laser-light damage to tissue, particularly human, is quite desirous for obvious scientific, political, and fiduciary reasons. We assessed the sublethal insult to human cells using a tissue culture system for specific genes that have been shown to be important in several biological processes that could lead to cancer or cell death. Using the CAT-Tox (L) (Xenometrix, Inc.) assay, it appears that 1064 nm, nanosecond pulses of laser light is sensed and induces several stress response genes, including p53, a gene in the DNA repair and apoptosis (cell suicide) regulatory pathways in a dose dependent fashion. This approach provides insight into a more global methodology for characterizing environmental stressors via genetic profiling.

Genetic Induction of Cultured Human Cells by Femtosecond Pulse Laser-Light Exposure
Genetic Induction of Cultured Human Cells by Femtosecond Pulse Laser-Light Exposure

Author:

Publisher:

Published: 2000

Total Pages: 0

ISBN-13:

DOWNLOAD EBOOK

The use of laser light for targeting devices and weapons has sharply increased the likelihood that aircrew and support personnel will be exposed during operations. The increased potential for exposure of humans to laser light highlights the need for scientifically-based safety standards for laser exposure at the ultrashort pulse lengths. Current safety standards are largely extrapolations of exposure limits at longer pulse lengths using a minimal visible lesion endpoint in the Rhesus monkey retinal model. A non-animal model for assessing laser-light damage to tissue, particularly human, is quite desirous for obvious scientific, political, and fiduciary reasons. We assessed the sublethal insult to human cells using a tissue culture system for specific genes that have been shown to be important in several biological processes that could lead to cancer or cell death. Using the CAT-Tox (L) assay, it appears that 910 and 455 nm, femtosecond pulses of laser light is sensed and induces several stress response genes. Both wavelengths induced the xenobiotic receptor element in a roughly dose dependent fashion at 48 hours post exposure; while also inducing other genes to yield a genetic expression fingerprint unique to the exposure parameters. This approach provides insight into a more global methodology for characterizing environmental stressors via genetic profiling.

New Biomedical Applications of Near-infrared Femtosecond Laser Ablation
New Biomedical Applications of Near-infrared Femtosecond Laser Ablation

Author: Jinze Qiu

Publisher:

Published: 2010

Total Pages: 292

ISBN-13:

DOWNLOAD EBOOK

The main purpose of this research was to investigate new medical applications of femtosecond laser ablation. A near-infrared femtosecond laser was tested and proved to be able to overcome the existing limitations and outperform the conventional long-pulse lasers in the areas of human urinary calculus (kidney stone) lithotripsy and skin treatment. The two primary objectives of my research are: 1) to investigate the feasibility of using femtosecond pulsed laser radiation to ablate urinary calculus of various compositions. The laser-calculus interaction mechanism was characterized using pump probe imaging and fast flash imaging. A novel fiber delivery system was developed to transmit and focus high energy femtosecond pulses for urinary calculus lithotripsy. The successful demonstration of the femtosecond laser lithotripsy provided a promising treatment method better than the existing long-pulse laser lithotripsy in a few different aspects, including less collateral damage to surrounding tissue, small-size debris and more controlled experimental condition. 2) to investigate the depth limitation of femtosecond subsurface ablation in scattering skin sample and develop a prototype tissue optical clearing device to enhance femtosecond beam penetration for deeper subsurface cavitation production in the skin. The successful demonstration of the device has potential benefits to new femtosecond-based therapies for reshaping or removing subcutaneous tissues.

Laser Microirradiation of Cells
Laser Microirradiation of Cells

Author: Takahiro Kasuya

Publisher: Routledge

Published: 1989

Total Pages: 96

ISBN-13:

DOWNLOAD EBOOK

First volume in a new series designed to provide information quickly on current as well as promising developments in lasers and consisting of self-contained tracts and handbooks pertinent to laser science and technology. Five color plates. Annotation copyrighted by Book News, Inc., Portland, OR

Optical Manipulation of the Cell Cytoskeleton
Optical Manipulation of the Cell Cytoskeleton

Author: Nicole Mari Wakida

Publisher:

Published: 2010

Total Pages: 105

ISBN-13: 9781124215747

DOWNLOAD EBOOK

The use of shorter pulsed lasers for intracellular nanosurgery is of growing interest to understand complex biological processes. Here, we develop a femtosecond laser ablation system capable of irradiating multiple fluorescently labeled cytoskeletal elements. Transmission electron microscopy analysis of femtosecond irradiated regions of the cell demonstrate the laser's ability to target submicron regions of the cell. Ultrastructural analysis suggests no significant advantages over lasers with the shorter pulse durations. Irradiation of single microtubules demonstrates the effectiveness of the setup to precisely target a 0.25 micron structure, without affecting surrounding microtubules or regions within the cell. The efficiency of this irradiation process further facilitates the study of dynamics for microtubule depolyermization. Analysis of depolymerization rates confirms a statistically significant dependence on the time after irradiation as well as the relative location within the cell. The femtosecond laser system was then applied to the irradiation of the centrosome in migrating cells. The fluorescing centrosome region was targeted in multiple cell models including wound healing kidney epithelial cells (PtK2), single migrating human osteosarcoma cells (U2OS), and single fast migrating human neutrophils (HL60). Irradiation of the centrosome in U2OS cells resulted in a loss of polarized cell morphology at 30 to 90 minutes following laser exposure. This loss of polarization was associated with significant changes in the microtubule and actin network. Irradiation of the centrosome in wound edge PtK2 cells resulted in similar effects. Targeted PtK2 cells lost their ability to directionally migrate and often fell behind the neighboring control migrating cells. Ablation of the centrosome in neutrophils before and after chemoattractant was added resulted in a loss of polarized cell morphology. Unstable lamellae-like protrusions were often formed at random positions around the cell, however none were sufficient for migration in any direction. Responses of the various cell types to centrosome irradiation, in combination to the selective targeting of microtubules surrounding (but not including) the centrosome suggest a novel role of the centrosome. These studies suggest the centrosome maintains cell polarization through signal mediation rather than mechanically through the microtubule network.