Glossary

A

Acrosome

Organelle covering the head of a sperm and containing enzymes that digest the zona pellucida, thus permitting the sperm to enter the egg

ALH

Amplitude of lateral head displacement (µm, motility parameter of sperm).

Anaphase

Stage of cell division following metaphase in which the chromosomes move to opposite poles of the spindle

Andrology

Medical specialty dealing with male reproductive functions

Aneuploidy

An abnormal number of chromosomes

Assisted hatching (AH)

Zona pellucida drilling or zona pellucida thinning to facilitate the embryo´s hatching process

Assisted Reproduction

Collective term for all kinds of fertility treatment: intra uterine insemination (IUI), conventional IVF, ICSI

B

Birefringence

Decomposition of a ray of polarized light into two rays when it passes through certain types of material

Blastocyst

Early mammalian embryo (human: day 5/6 of development), consisting of an inner cell mass, a cavity, and an outer layer, the trophoblast

Blastomere

Embryonic cell produced during early cleavage

Bright field microscopy

= Transmitted light microscopy, simplest of all the optical microscopy illumination techniques where the sample is illuminated from one direction and observed from the other direction

C

Cane

Clamp made from aluminium to fix goblets or cryo vials to for cryo storage

CASA

Computer-aided sperm analysis

CE

Conformity mark on many products placed on the single market in the European Economic Area

Circular polarizer

Polarizer producing polarized light  consisting of two perpendicular electromagnetic plane waves of equal amplitude and 90° difference in phase

Cleavage stage embryo

Early mammalian embryo, consisting of 2-12 embryonic cells (blastomeres)

c-mount

Standardized mount for digital cameras or camera objectives

Condenser

Lens that serves to concentrate light from the illumination source of a microscope and to focus the light through the object

Cryopreservation

Long-term preservation of viability through slow or rapid cooling and storage close to –196 °C

D

DIC

Differential interference contrast microscopy (also known as Nomarski interference contrast), an optical microscopy illumination technique involving polarized light which is used to enhance the contrast in transparent samples

Dichroic mirror

Very accurate mirror which selectively reflects light of a small range of colors while other colors will pass

E

Embryo

Early developmental stage of plants or animals lasting until the end of the first trimester in humans

Embryo transfer

Retransfer of the embryos to the mother´s uterus after IVF

F

FDA

U.S. Food and Drug Administration, being responsible for pharmaceutical drug and food safety

FPS

Frames per second, dimension of the frame rate of videos

G

Gamete

Mature sexual reproductive cell, sperm or oocyte

GIF

Green interference filter

Goblet

Tube with a closed bottom for storage of cryo straws in liquid nitrogen; has to be fixed to a cane

H

HEPA filter

High efficiency particulate air filter

HEPES

4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, a zwitterionic organic chemical buffering agent

I

ICSI

Intracytoplasmic sperm injection

IMSI

Intracytoplasmic, morphologically selected sperm injection, microinjection of sperm after morphological examination under high magnification

in vitro

In culture outside the body

Infrared

Part of the invisible spectrum of light comprising wavelengths between 800 nm and 1 mm

IUI

Intra uterine insemination

IVF

In vitro fertilization

K

Koehler alignment

Optimum alignment of the microscope optical components

L

LAH

Laser assisted hatching, the common way of performing assisted hatching

LAL

Limulus Ameobocyte Lysate Gel-Clot Assay, a sensitive and specific test to screen medical devices and raw materials for the presence of harmful levels of endotoxin

Laser

Light amplification by stimulated emission of radiation

LC

Liquid crystal

LN₂

Liquid nitrogen (-196°C)

Luminophore

A chemical compound that manifests luminescence (emission of light by a substance)

M

MEA

Mouse embryo assay to test disposables for biocompatibility

Meiosis

Part of the process of gamete formation in the course of which the diploid chromosome number is reduced to the haploid

Metaphase

Stage of cell division in which the chromosomes line up along the equatorial plane of the spindle

Micro manipulator

Motorized, hydraulic or mechanical device used to physically interact with a sample under a microscope, where a level of precision of movement is necessary that cannot be achieved by the unaided human hand

Microinjector

Device which provides the pressure which is needed to deliver a sample solution from a micropipette into cells

Midpiece

Forepart of the sperm tail, connecting the tail to the sperm head; carries the mitochondria

Monogenic disease

Diseases resulting from modifications in a single gene

mpix

Megapixel, 1 million pixels, a term used for the number of pixels in an image or to express the number of image sensor elements of digital cameras

MSOME

Morphological selection of motile spermatozoa, applied for diagnostic purposes

N

N.A. (numerical aperture)

a dimensionless number that characterizes the range of angles over which the system can accept light; the greater the N.A., the greater is the resolving power of an optical lens

O

Oil immersion

Technique used to increase the resolution of a microscope by immersing both the objective lens and the specimen in an oil of high refractive index

Ovum pick-up (OPU)

Transvaginal aspiration of follicular fluid and oocytes from follicles

P

PGD

Preimplantation Genetic Diagnosis (any genetic diagnosis of gametes or early embryonic cells prior to embryo transfer)

Phase contrast

Optical microscopy illumination technique in which small phase shifts in the light passing through a transparent specimen are converted into contrast changes in the image

Polar body biopsy

Removal of the first and second polar body of an oocyte through an opening in the zona pellucida for genetic analysis

Polarization microscopy

Microscopy using polarized light to visualize certain structures

Polarized light

Beam of light where the waves are vibrating in the same direction

Pronuclear stage

Oocyte with visible male and female nuclei on the eve of completing fertilization

Prophase

Preparatory stage of cell division

PVA

Polyvinyl alcohol, a water-soluble synthetic polymer which gelatinizes when wetted

R

Retardance

Difference in phase shift between two characteristic polarizations of light upon reflection from an interface

S

Seeding

Here: induction of ice crystal formation

Sequential media

Series of two media of different composition used for fertilization and human embryo culture from days 1 to 3 and days 4 to 6, respectively

Single Step Medium

Universal medium for fertilization and human embryo culture from days 1 to 6

Sleeve

Sheath tube to protect cryo vials or goblets fixed to a cane

Slow freezing

Defined, stepwise cooling of gametes or embryos from room temperature to -196°C while the cells are in osmotic equilibrium with their environment

Spermiogram

Examination of an ejaculate, mainly focusing on sperm concentration, motility and morphology

Spindle

Barrel-shaped protein structure arranging and separating chromosomes during cell division

Straw

Straw shaped container for cryopreservation and storage of gametes and embryos

T

Tail

Here: flagellum of a sperm

Telophase

Final stage of cell division in which the separated chromosomes reach the opposite poles of the dividing cell and the spindle is constricted by the forming cell membranes

TESE

Testicular sperm extraction, retrieval of sperm from testicular tissue

Time lapse

Video recording technique whereby each frame is captured at a rate much slower than it will be played back

Treatment cycle

Artificial cycle involving hormonal stimulation of the ovaries and subsequent IUI, IVF or ICSI

Trinocular tube

Part of a microscope carrying the eyepieces and a third tube for attaching a camera

Trophectoderm

Cell layer from which the trophoblast (=outer layer of the mammalian blastocyst) differentiates

U

USB

Universal serial bus, a specification to establish communication between devices

V

VAP

Average path velocity (µm/sec, motility parameter of sperm)

VCL

Curvilinear velocity (µm/sec, motility parameter of sperm)

Vitrification

Transition of a substance into a glass by ultra-rapid cooling, avoiding ice crystal formation

VSL

Straight-line velocity (mm/sec, motility parameter of sperm)

W

Working distance

Distance between the front lens of an objective or condenser and the object

Z

Zona drilling

Opening the zona pellucida of oocytes or embryos; commonly performed using a microsurgical laser

Zona pellucida

Spherical protein envelope surrounding mammalian oocytes and early embryos

Zona scoring

Assessment of oocyte developmental competence by analyzing the birefringence properties of the inner layer of the zona pellucida

Zona thinning

Removal of the outer layers of the zona pellucida over a quarter of the zona circumference to facilitate the embryo´s hatching process; commonly performed using a microsurgical laser

Zygote

Cell synthesized from the union of two gametes after fusion of male and female genetic material