Reconstruction of the neuromuscular system of the swimming-type larva of Loxosomella atkinsae (Entoprocta) as inferred by fluorescence labelling and confocal microscopy

Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10-5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.

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Measurement of spontaneous neuronal membrane activity by time lapse confocal microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141238 ◽

1995 ◽

Vol 53 ◽

pp. 972-973

Author(s):

R H. Selinfreund ◽

A. H. Cornell-Bell

Keyword(s):

Membrane Potential ◽

Confocal Microscopy ◽

Patch Clamp ◽

Electrical Activity ◽

Time Lapse ◽

Neuronal Firing ◽

Neuronal Membrane ◽

Pituitary Cells ◽

Patch Clamp Recording ◽

Spontaneous Electrical Activity

Cellular electrophysiological properties are normally monitored by standard patch clamp techniques . The combination of membrane potential dyes with time-lapse laser confocal microscopy provides a more direct, least destructive rapid method for monitoring changes in neuronal electrical activity. Using membrane potential dyes we found that spontaneous action potential firing can be detected using time-lapse confocal microscopy. Initially, patch clamp recording techniques were used to verify spontaneous electrical activity in GH4\C1 pituitary cells. It was found that serum depleted cells had reduced spontaneous electrical activity. Brief exposure to the serum derived growth factor, IGF-1, reconstituted electrical activity. We have examined the possibility of developing a rapid fluorescent assay to measure neuronal activity using membrane potential dyes. This neuronal regeneration assay has been adapted to run on a confocal microscope. Quantitative fluorescence is then used to measure a compounds ability to regenerate neuronal firing.The membrane potential dye di-8-ANEPPS was selected for these experiments. Di-8- ANEPPS is internalized slowly, has a high signal to noise ratio (40:1), has a linear fluorescent response to change in voltage.

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Five-Dimensional Microscopy using Widefield-Deconvolution: Practical Considerations and Biological Applications

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163800 ◽

1996 ◽

Vol 54 ◽

pp. 268-269

Author(s):

W.F. Marshall ◽

K. Oegema ◽

J. Nunnari ◽

A.F. Straight ◽

D.A. Agard ◽

...

Keyword(s):

Confocal Microscopy ◽

High Speed ◽

Laser Scanning ◽

Ccd Camera ◽

Image Plane ◽

Time Lapse ◽

Laser Scanning Confocal Microscopy ◽

Three Dimensions ◽

Excitation Light ◽

Cooled Ccd

The ability to image cells in three dimensions has brought about a revolution in biological microscopy, enabling many questions to be asked which would be inaccessible without this capability. There are currently two major methods of three dimensional microscopy: laser-scanning confocal microscopy and widefield-deconvolution microscopy. The method of widefield-deconvolution uses a cooled CCD to acquire images from a standard widefield microscope, and then computationally removes out of focus blur. Using such a scheme, it is easy to acquire time-lapse 3D images of living cells without killing them, and to do so for multiple wavelengths (using computer-controlled filter wheels). Thus, it is now not only feasible, but routine, to perform five dimensional microscopy (three spatial dimensions, plus time, plus wavelength).Widefield-deconvolution has several advantages over confocal microscopy. The two main advantages are high speed of acquisition (because there is no scanning, a single optical section is acquired at a time by using a cooled CCD camera) and the use of low excitation light levels Excitation intensity can be much lower than in a confocal microscope for three reasons: 1) longer exposures can be taken since the entire 512x512 image plane is acquired in parallel, so that dwell time is not an issue, 2) the higher quantum efficiently of a CCD detect over those typically used in confocal microscopy (although this is expected to change due to advances in confocal detector technology), and 3) because no pinhole is used to reject light, a much larger fraction of the emitted light is collected. Thus we can typically acquire images with thousands of photons per pixel using a mercury lamp, instead of a laser, for illumination. The use of low excitation light is critical for living samples, and also reduces bleaching. The high speed of widefield microscopy is also essential for time-lapse 3D microscopy, since one must acquire images quickly enough to resolve interesting events.

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Laser Scanning Confocal Microscopy and Three-Dimesnsional Reconstruction of the Mitotic Spindles of Unequally Dividing Embryonic Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158376 ◽

1990 ◽

Vol 48 (3) ◽

pp. 166-167

Author(s):

J. Holy ◽

G. Schatten

Keyword(s):

Confocal Microscopy ◽

Mitotic Spindle ◽

Laser Scanning ◽

Three Dimensional ◽

Laser Scanning Confocal Microscopy ◽

Two Dimensions ◽

Embryonic Cells ◽

Mitotic Spindles ◽

Cleavage Division ◽

Scanning Confocal Microscopy

One of the classic limitations of light microscopy has been the fact that three dimensional biological events could only be visualized in two dimensions. Recently, this shortcoming has been overcome by combining the technologies of laser scanning confocal microscopy (LSCM) and computer processing of microscopical data by volume rendering methods. We have employed these techniques to examine morphogenetic events characterizing early development of sea urchin embryos. Specifically, the fourth cleavage division was examined because it is at this point that the first morphological signs of cell differentiation appear, manifested in the production of macromeres and micromeres by unequally dividing vegetal blastomeres.The mitotic spindle within vegetal blastomeres undergoing unequal cleavage are highly polarized and develop specialized, flattened asters toward the micromere pole. In order to reconstruct the three-dimensional features of these spindles, both isolated spindles and intact, extracted embryos were fluorescently labeled with antibodies directed against either centrosomes or tubulin.

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Two-photon excitation fluorescence microscopy in living systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146618 ◽

1993 ◽

Vol 51 ◽

pp. 154-155 ◽

Cited By ~ 1

Author(s):

David W. Piston

Keyword(s):

Confocal Microscopy ◽

Fluorescence Microscopy ◽

Singlet State ◽

Excited Electronic State ◽

Input Power ◽

Two Photon ◽

Simultaneous Absorption ◽

Photon Excitation ◽

Very High ◽

Two Photon Excitation

Two-photon excitation fluorescence microscopy provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In our fluorescence experiments, the final excited state is the same singlet state that is populated during a conventional fluorescence experiment. Thus, the fluorophore exhibits the same emission properties (e.g. wavelength shifts, environmental sensitivity) used in typical biological microscopy studies. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10−5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.

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Selected Papers on Confocal Microscopy

Journal of Microscopy ◽

10.1046/j.1365-2818.1998.0270b.x ◽

1998 ◽

Vol 189 (1) ◽

pp. 98-99

Author(s):

Alan Entwistle

Keyword(s):

Confocal Microscopy

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Effect of caffeine on the neuromuscular system in rats: an immunohistochemical study

Planta Medica ◽

10.1055/s-0029-1234740 ◽

2009 ◽

Vol 75 (09) ◽

Author(s):

P Lo Cascio ◽

ER Lauriano ◽

A Leuzzi ◽

L Campolo ◽

M Calò ◽

...

Keyword(s):

Immunohistochemical Study ◽

Neuromuscular System

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Asociación entre hábitos parafuncionales de la cavidad bucal y los transtornos temporomandibulares en adolescentes

REVISTA ODONTOLOGÍA PEDIÁTRICA ◽

10.33738/spo.v10i2.167 ◽

2018 ◽

Vol 10 (2) ◽

Author(s):

Gabriel Muñoz Quintana

Keyword(s):

Oral Cavity ◽

Temporomandibular Joint ◽

Temporomandibular Disorders ◽

Temporomandibular Disorder ◽

Neuromuscular System ◽

Jaw Movements ◽

Nail Biting ◽

Palabras Clave ◽

Masticatory System ◽

Objective Being

La musculatura del sistema masticatorio y la articulación temporomandibular (ATM) están protegidos por reflejos nerviosos básicos y sistema neuromuscular a través de la coordinación de fuerzas musculares, todo lo que produce sobrecarga muscular repetitiva como los hábitos parafuncionales (HPF) pueden ocasionar trastornos temporomandibulares (TTM)1. Los HPF se caracterizan por movimientos anormales a la función mandibular normal sin objetivo funcional, al estar alterados constituyen una fuente productora de fuerzas traumáticas caracterizadas por dirección anormal, intensidad excesiva y repetición frecuente y duradera (Rolando Castillo Hernández, 2001)4. El objetivo del estudio fue identificar la asociación entre la presencia de hábitos parafuncionales de la cavidad bucal y los TTM en adolescentes de la ciudad de Puebla. Estudio observacional descriptivo. Se incluyeron 258 adolescentes, 132 (51.2%) mujeres y 126 (48.8%) hombres, con una edad promedio de 12.5±.73 y quienes fueron diagnosticados con los CDI/TTM y los HPF fueron auto-reportados por los pacientes. Se encontró una prevalencia de los TTM del 39.9% y una prevalencia de HPF del 86%. Los HPF más frecuentemente reportados fueron la succión labial y la onicofagia. Se encontró una asociación significativa (x2=7.31, p=0.007) entre los hábitos parafuncionales y los TTM en adolescentes. Palabras clave: Trastornos temporomandibulares, hábitos parafuncionales, adolescentes, articulación temporomandibular. Abstract The muscles of the masticatory system and temporomandibular joint (TMJ) are protected by basic nerve reflex and neuromuscular system through the coordination of muscle forces, all that repetitive muscle overload occurs as habit parafunctional (HPF) can cause temporomandibular disorder TMD)1. The characteristics of HPF are abnormal jaw movements without a functional objective. Being the jaw movements altered, they constitute a source of traumatic forces with an abnormal direction, excessive intensity and long-lasting and frequent duration. (Rolando Hernandez Castillo 2001)4. Objective: was to identify the association between the presences of parafunctional habits of the oral cavity and TMD in adolescents in the Puebla city in Mexico. Material and methods: Is a observational study, we included 258 adolescents 132 (51%) females and 126 (48.8%) were men, mean age 12.5±.73 and who were diagnosed with CDI/TTM and HPF were self- reported by patients. Results: The prevalence of TMD was 39.9% and a prevalence of 86% HPF. The most frequently reported HPF were lip sucking and nail biting. We found a significant association (x2= 7.31, p = 0,007) between HPF and TMD in adolescents. Key words: Parafunctional habits of oral cavity, temporomandibular disorders, temporomandibular joint. (Odontol Pediatr 2011;10(2): 90-94).

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