Descargar la presentación
La descarga está en progreso. Por favor, espere
Publicada porEva María Espejo Robles Modificado hace 8 años
1
| Curso Electivo Teórico-Práctico | Análisis Cuantitativo de Colocalización en Microscopía Confocal 10-17 |08|2007 Steffen Härtel Programa de Anatomía y Biología del Desarollo, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile ICBM
2
|-> Rodrigo Castillo: viernes, 10.08.07 @ 9.30-13.00 Measurement of colocalization of objects in dual-color confocal images Manders E. (1993) Journal of Microscopy 169: 375-382 |-> Ivan Alfarro: lunes, 13.08.07 @ 15-18.30 STED-Microscopy: Concepts for nanoscale resolution in fluorescence microscopy Hell S., Dyba, M., Jakobs S (2004) Current Opinion in Neurobiology 4:599-609 |-> Valentina Parra: lunes, 13.08.07 @ 15-18.30 Automatic and Quantitative Measurement of Protein-Protein Colocalization in Live Cells Costes et al. 2004 Biophys. J. 86, 3993–4003 |-> Ariel Contreras: martes, 14.08.07 @ 9.30-13.00 A syntaxin 1, Galphao, and N-type calcium channel complex at a presynaptic nerve terminal: analysis by quantitative immunocolocalization Li, Q., Lau, A., Morris, T.J., Guo, L., Fordyce, C.B. & Stanley, E.F. (2004) J. Neurosci. 24, 4070–4081 |-> Barbra Toro: jueves, 16.08.07 @ 9.30-13.00 Co-localization analysis of complex formation among membrane proteins by computerized fluorescence microscopy: application to immunofluorescence co-patching studies Lachmanovich, E., Shvartsman, D.E., Malka, Y., Botvin, C., Henis, Y.I. & Weiss, A.M. (2003) Journal of Microscopy. 212, 122–131 |-> Nancy Leal: jueves, 16.08.07 @ 9.30-13.00 Partial colocalization of glucocorticoid and mineralocorticoid receptors in discrete compartments in nuclei of rat hippocampus neurons Van Steensel, B., van Binnendijk, E., Hornsby, C., van der Voort, H., Krozowski, Z., de Kloet, E. & van Driel, R. (1996) J. Cell Sci. 109, 787–792 |-> Ximena Verges: viernes, 17.08.07 @ 9.30-13.00 Multicolour analysis and local image correlation in confocal microscopy Demandolx, D. & Davoust, J. (1997) Journal of Microscopy 185, 21–36 |-> Leonel Muñoz: viernes, 17.08.07 @ 9.30-13.00 A guided tour into subcellular colocalization analysis in light microscopy Bolte S. & Cordelieres P. (2006) Journal of Microscopy, 224 (3): 213–232 |-> Seminarios
3
I|-> Intensity The observation volume (femtoliter) defined by the Point Spread Function must be considered as a mini-sprectrofluorimeter. Consider the Offset I(0) in order to calibrate your signal I(0) 0 ! Never saturate the signal: I I max (255 for 8 bit) ! I(0) > 0 I > I max
4
II|-> Refractive index Use the right inmersion setup ! n1 = n2 ! Keep refractive index / index of refraction constant !
5
The sampling frequency (or sampling distance) is a function of the observation volume (femtoliter) defined by the Point Spread Function (PSF): Consider sampling distances in x and y 50 nm and z 150-300 nm for later deconvolution, or calculate the explicit sample distances directly. http://support.svi.nl/wiki/NyquistCalculator III|-> Nyquist
6
I. Image Adquisition I.a|-> Fundamentos de la microscopía confocal I.b|-> Fundamentos de la fluorescencia II. Deconvolution III. SegmentationIV. Analisys |-> what‘s up
7
Interacciones... intra- e inter moleculares... producen cambios... espectrales tiempos de vida polarización intensidad... - Fluorescencia - Fosforescencia Luminescencia: t ~ 10 -8 s t ~ 10 -3 -10 0 s Absorción / Excitación t Emissión |-> Fluorescencia
8
Intercombinación 10 -8 s 10 -6 - 1s Transiciones: con radiación Niveles: vibracionales sin radiación | -> calor electrónicos -> transferencia de energía (FRET) -> radicales... STED 10 -9 -10 -8 s Fluorescencia 10 -6 - 1s Fosforescencia 10 -15 s Absorción 10 -12 s Conversión interna x/y z |-> Jablonski Diagram
9
ENERGY Distance [r] Frank Condon : ‘Transiciones entre niveles electrónicos ocurren mucho mas rápido que movimientos de núcleos moleculares.‘ (masa electron / masa atom : 1 : 2000) -> Mirror Image Rule Stokes (Shift) : ‘ La energía de emisión es menor a la energía de excitación.‘ |-> Franck Condon
10
|-> Mirror Image Rule
11
a: DPH. b: TMA-DPH, c: Carboxyl –DPH. Momentos dipolares µ de absorción y emission son parallelos. Polarización Anisotropía a MAX = 0,39 I II ~cos ² a( ) (a) , viscosidad |-> Polarisación
12
Probabilidad p :p(r DA ) ~ r DA -6 [Förster, 1946] Efectivo sólo para distancias :r DA < 150 Å Molecule 1 ( DONOR )Molecule 2 ( ACCEPTOR ) Energy Transfer (Fluorescence) Resonance Energy Transfer: (F)RET |-> FRET
13
occurs from the excited-state (*) of a donor (D) to an acceptor (A). h + D + A D* + A D + A* D + A + h ‘ occurs w/o the generation of an intermediate photon h ‘‘.... D* + A (D + A + h ‘‘) D + A* ..., (reabsorption ~ 1/r²) occurs as a result of long-range dipole-dipole interactions between the ´oszillating dipoles´ D & A., depends on the spectral overlap between D emission and A excitation., the quantum yield (QY) of D: QY = [h ‘‘] / ([h ‘‘] + k nr ), the relative orientation of D & A transition dipoles. occurs from the excited-state (*) of a donor (D) to an acceptor (A). h + D + A D* + A D + A* D + A + h ‘ occurs from the excited-state (*) of a donor (D) to an acceptor (A). h + D + A D* + A D + A* D + A + h ‘ occurs w/o the generation of an intermediate photon h ‘‘.... D* + A (D + A + h ‘‘) D + A* ..., (reabsorption ~ 1/r²) |-> FRET
14
Transiciones: con radiación Niveles: ---- vibracionales sin radiación electrónicos DonorAcceptor |-> FRET
15
the rate k T of RET is given by : k T = 1/ D · (R 0 /r) 6, D decay time of D w/o A. I(t) = I 0 exp(-t/ D ), r distance between D & A., R 0 Förster distance (20-90 Å). R 0 6 = 8.78·10 -5 · QY D · ² · n -4 · J( ), n refractive index: n² = · (n ~1.4 biomolecules in aq). : electric permittivity, : magnetic permeability, orientation between transition dipoles, ² ~2/3 random, J( ) overlap integral between D-emission & A-excitation., QY = [h ‘‘] / ([h ‘‘] + k nr ) |-> FRET
16
the transfer quantum yield / energy transfer efficiency E is given by: E = k T / ( D -1 + k T ) | (k T = 1/ D · (R 0 /r) 6 ) = 1 / (1 + (r/R 0 ) 6 ), 2D* + 2A D + D* + A + A* 2D + 2A + h ‘ + h ‘‘, E(r =2R 0 ) = 0.0156, E(r =0.1R 0 ) = 0.99999 R 0 : 20 - 90 Å detecta cambios conformacionales dentro de macromoleculas. detecta proximidades entre moleculas mas alla de la resolución optica. Literature: - Joseph R. Lakowicz, Principles of Fluorescence Spectroscopy, Kluwer Academic Publishers, ISBN:0306412853. - Jares-Erijman E.A. and Jovin T.M. (2003) FRET imaging. Nat. Biotechnol. 21(11): 1387-95. - R. Röder, Einführung in die molekulare Photobiophysik, Teubner, ISBN:3519032414., E = ½ at r = R 0 : |-> FRET
17
|-> Colores
19
PC distance (pixel) PC distance (pixel) PC
20
|-> Colores http://webvision.med.utah.edu/KallSpatial.html
21
Bastones Conos (S, M, L) -> 10 8 Bastones -> 6·10 6 Conos: L : M : S (primates) 580 nm : 545 nm : 420 nm ~10: ~10: 1 en cantidad y sensitividad La fóvea |-> Colores
22
-> 10 8 Bastones -> 6·10 6 Conos: [Azul] / [Amarillo]: [+S] / [M+L] [Verde] / [Rojo]: [M-L] / [L-M] S - Conos M - Conos L - Conos ‘Midget-Cell‘ |-> Colores
23
10 8 Conos & bastones Nervus opticus 8· 10 5 Células horizontales Células bipolares [Glutamato]~1/I Células amacrin Celulas del Ganglio Células del ganglio Se conocen~15 tipos diferentes de células de ganglio. |-> Colores
24
->[I, L, M, S, x, y, t] - Receptores: - [Glu] ~ [Na + ] en ‘Off-cells‘ bipolares - [Glu] ~ [Na + ] -1 en ‘On-cells‘ bipolares ->[] = [] + [dI/dt, dL/dt, dM/dt, dS/dt] ->[] = [] + [z] - Activación/Inhibición lateral: - Células horizontales emiten GABA, en caso de una excitación homogenia en [x,y] ->[] = [] + [dI/dxy, dL/dxy, dM/dxy, dS/dxy] |-> Colores
25
Representación simbólica o modelo individual del mundo real
26
Alessandro Rizzi GIC - Graphic, Imaging and Color research group Università di Milano http://www.dti.unimi.it/~rizzi/ |-> Colores
27
RGB (Red Green Blue), (R:0-255, G: 0-255, B:0-255) : R G B H V S HSV (Hue Saturation Value), (H:0-2 , S:0-1, V:0-1) |-> Colores
28
http://www.wikipedia.org/wiki/HSV_color_space The Hue Saturation Value (or HSV) model defines a color spacecolor space in terms of three constituent components: HueHue, the color type (such as red, blue, or yellow); Measured in values of 0-360 by the central tendency of ist wavelength SaturationSaturation, the 'intensity' of the color (or how much greyness is present), Measured in values of 0-100% by the amplitude of the wavelength. ValueValue, the brightness of the color. Measured in values of 0-100% by the spread of the wavelength HSV is a non-linear transformation of the RGB color space.non-lineartransformationRGB color space
29
-> RGB.....Se puede usar muy bien para fines científicos pero no sirve para obtener una medida para lo que el ser humano califica como diferencia entre colores (R 1 G 1 B 1 ) y (R 2 G 2 B 2 ). -> Diferencia entre (H 1 S 1 I 1 ) y (H 2 S 2 I 2 ): |-> Colores
30
I( 290,267 ) = 220 r g b 0 : 220 : 255 0 : 220 : 255 0 : 220 : 255 Una mesa de color está definida por 3 vectores r, g, b de 8 bits. Amarillo (255, 255, 0) Negro (0, 0, 0) Rojo (255, 0, 0) Verde (0, 255, 0) Blanco (255, 255, 255) Cian (0, 255, 255) Magenta (255, 0, 255) Azul (0, 0, 255) red = [r 0, r 1,…...…...,r 255 ] green = [g 0, g 1,……...,g 255 ] blue = [b 0, b 1,……...,b 255 ] Un canal tiene 8 bits y se pueden codificar 256 colores o intensidades |-> Colores
31
r g b 000::::0::0000::::0::0 0 1 2 : 200 : 255 000::::0::0000::::0::0 |-> Colores
32
r g b 0 1 2 : 220 : 255 000::::0::0000::::0::0 000::::0::0000::::0::0 |-> Colores
33
r = [r 0, r 1, r 2,…...., r 255 ] = [0, 0, 0,……..,0] g = [g 0, g 1, g 2,…, g 255 ] = [0, 1, 2,…..,255] b = [b 0, b 1, b 2,…., b 255 ] = [0, 0, 0,……..,0] o = [o 0, o 1, o 2,….., o 255 ] = [255, 255,.,255] r = [r 0, r 1, r 2,…...., r 255 ] = [0, 1, 2,…..,255] g = [g 0, g 1, g 2,…, g 255 ] = [0, 0, 0,……..,0] b = [b 0, b 1, b 2,…., b 255 ] = [0, 0, 0,……..,0] o = [o 0, o 1, o 2,….., o 255 ] = [80, 80,…….,80] |-> Colores
38
|-> Localization Standard error of the mean (SE) The standard error of the mean of a sample from a population is the standard deviation of the sampling distribution of the mean, and may be estimated by the formula:populationstandard deviationsampling distribution Where is an estimate of the standard deviation σ of the population, an n is the size (number of items) of the sample.
39
|-> ICA or ICQ ICA / ICQ Intensity Correlation Analysis /Quotient
40
ICQ Є [± 0.5] Intensity Correlation Quotient |-> ICQ Sign Test p ≤ 0.5 Σ ( N!/( i ! (N-i) ! )) i = 1,k (k = min(n+,n-)) One-Sample and Matched-Pairs tests Sign Test McNemar's Test Wilcoxon Matched-Pairs Signed-Ranks Test Student-t test for one sample
41
|-> ICQ Sign Test p ≤ 0.5 Σ ( N!/( i ! (N-i) ! )) i = 1,k (k = min(n+,n-)) http://www.fon.hum.uva.nl/Service/Statistics/Sign_Test.html Characteristics: Crudest and most insensitive test. It is also the most convincing and easiest to apply. The level of significance can almost be estimated without the help of a calculator or table... Approximation: For N > 30, the Student t-test can be used. However, the Wilcoxon Matched-Pairs Signed-Ranks test is a better alternative.Student t-testWilcoxon Matched-Pairs Signed-Ranks Remarks: The Sign-test answers the question: How often?, whereas other tests answer the question How much?. It must be kept in mind that these two questions might have different answers. When the problem concerns the sizes of the differences, the Wilcoxon Matched-Pairs Signed-Ranks Test should be preferred.Wilcoxon Matched-Pairs Signed-Ranks Test Finally, the Sign-test is an almost ideal quick-and-dirty test that can be used to browse datasets or to check the results of other tests (e.g., as in: "All six subjects show an increase, so why does your test insist that p > 0.05?").
Presentaciones similares
© 2024 SlidePlayer.es Inc.
All rights reserved.