Name: fish for pre-implantation genetic diagnosis
Uploaded: 2011-02-23T18:30:00
Duration: 7 min 34 s
Description: Watch this Scientific Journal Video about FISH for Pre-implantation Genetic Diagnosis at JoVE.com

1. 	Lysing and Spreading a Nucleus from a Biopsied Blastomere
<ol>
<li>Cell lysis buffer for spreading cells (0.2% Tween20 in 0.01 M HCl, pH 2.0) should be prepared 24 hours in advance and stored at -20&deg;C. Prepare 100 mL and filter 20 mL into a 30 mL sterile universal container using a sterile 20 mL syringe and syringe filter. Dispense 1 mL aliquots into 10-15 1.7 mL sterile microcentrifuge tubes, close and label the tubes prior to freezing. It is recommended to have two different batches is use, the new batch and the previous batch, which has been tested and can be used if the new batch is unsatisfactory.</li>
<li>Defrost the lysis buffer at room temperature 30 minutes before the biopsy procedure. For practical purposes the working temperature will be between room temperature and hand temperature.</li>
<li>Score a small circle (approximately 5 mm diameter) on the underside of an amine-coated slide (e.g. Genetix) using a diamond pen and pre-label the slide with the case number, unique slide number, and biopsy date. Use a separate slide for each blastomere in numerical order, and label with the embryo number. Slides should be labeled with a hard pencil such as 4H, and "blotted" with a latex glove to remove any graphite dust.</li>
<li>Place a small volume of lysis buffer within the circle.</li>
<li>Transfer the biopsied blastomere into the lysis buffer. If necessary add lysis buffer within the circle until the cell begins to lyse; the cell should lyse completely and the cytoplasm disperse before the buffer dries.</li>
<li>Observe the nucleus to ensure that it remains within the circle and is not lost; if the cell does not have a nucleus or has multiple nuclei, biopsy another cell.</li>
<li>Leave the slide to air-dry at room temperature.</li>
</ol>
2. 	In Situ Hybridization of a Single Blastomere Nucleus
<ol>
<li>Prepare an ethanol series (70, 90 and 100%) made up in sterile distilled water.</li>
<li>Turn on and set the hot block (e.g. Hybaid Omnislide or Vysis Hybrite) to 75&deg;C.</li>
<li>Defrost probes, vortex, and centrifuge. The reagents should be witnessed and verified to be correct before making up the probe mixture. Pipette volumes as specified by the manufacturer to make up the probe mixture in a 0.65 mL sterile microcentrifuge tube and vortex and centrifuge before use. The total volume of probe mixture should be sufficient to allow 2 &mu;L per nucleus to be tested and rounded up to the nearest 10 &mu;L to allow a safety margin.</li>
<li>Pre-wash the slides in coplin jars using phosphate-buffered saline (PBS) (pH 7.0: 0.14 M NaCl, 3 mM KCl, 10 mM Na2HPO4, 2 mM KH2PO4) for 5 min at room temperature.</li>
<li>Rinse the slides twice in sterile distilled water.</li>
<li>Dehydrate the slides with the ethanol series (70, 90, and 100%) for 2 min each at room temperature and air-dry. Ensure slides are fully immersed and if any graphite dust floats to the surface, soak up with a clean tissue.</li>
<li>Record the position of the nucleus within the circle by visualizing with a phase contrast microscope.</li>
<li>Dehydrate with 100% ethanol for 2 min at room temperature and air-dry.</li>
<li>Apply 2 &mu;L of probe mixture, and cover with a 9 x 9 mm coverslip (one quarter of an 18 x 18 mm no.1 coverslip).</li>
<li>Seal the edges of the coverslip with rubber cement (e.g. Cow Gum; Cow Proofing).</li>
<li>Codenature the slides on a hot block at 75&deg;C for 5 min, and then hybridize the slides overnight (16-20 h) in a humidified chamber at 37&deg;C. Probe mixes that consist entirely of centromere probes (i.e. for sex-linked cases) will give a satisfactory result after 60 min of hybridization.</li>
<li>Prepare a water bath with sufficient coplin jars and heat to 71&deg;C.</li>
<li>Prepare a 0.4x standard saline citrate (SSC) stringent wash solution (pH 7.0 at 71&deg;C, 0.06 M NaCl, 6 mM C6H5Na3O7.2H2O) and heat in the water bath.</li>
<li>Dispense 50 mL of stringent wash per coplin jar required and check that the temperature is 71&deg;C immediately prior to use using a clean thermometer.</li>
<li>Carefully remove the rubber cement from each slide and rinse off the coverslip using 4x SSC/0.05% Tween20 (pH 7.0) at room temperature.</li>
<li>Wash the slides in the 0.4x SSC stringent wash at 71&deg;C for 5 min. Wash no more than 6 slides per coplin jar.</li>
<li>Wash the slides in 4x SSC/0.05% Tween20 at room temperature for 2 min.</li>
<li>If the probe mix contains indirectly labelled probe(s), drain the slides of excess liquid and apply 20 &mu;L of fluorescently conjugated antibody under a 20 x 20 mm square of Parafilm.</li>
<li>Incubate in a humidified chamber at 37&deg;C for 15 min.</li>
<li>Remove the Parafilm and wash once in 4x SSC/0.05% Tween20 at room temperature for 2 min.</li>
<li>Wash twice for 2 min in PBS at room temperature and drain the slides.</li>
<li>Apply 6 &mu;L of DAPI/Vectashield (160 ng of 4',6-diamidino-2-phenylindole dihydrochloride in 1 mL of Vectashield mounting medium, Vector Laboratories) to a 22 x 22 mm no. 0 coverslip and invert the slide over the coverslip.</li>
<li>Blot and seal the edges of the coverslip with clear nail varnish.</li>
</ol>
3. 	Analysis using a Fluorescence Microscope Suitably Equipped with Appropriate Filters for the Probes Used.
<ol>
<li>Score signals by direct visualization using a fluorescence microscope and single band-pass filters for each fluorochrome in the assay. Each nucleus should be scored by two analysts. A general guideline should lead to scoring of a single signal where two closely spaced signals are less than one domain (signal-width) apart; however, judgment based on experience needs to be exercised to interpret signals of varying size, intensity, and separation.</li>
<li>Use imaging software (e.g. Isis, MetaSystems, Altlussheim, Germany; CytoVision, Genetix) to capture an image of the nucleus for confirmation of the visual diagnosis, and for image archiving as part of a laboratory quality assurance plan.</li>
</ol>
4. Representative Results:
Metaphase and interphase nuclei from cultured peripheral blood lymphocytes should be examined to confirm that the selected probes are specific for the translocation chromosomes, informative for the breakpoints (the subtelomere probes should hybridize only to the translocated segments and the centromere probe(s) to the centric segment(s)) and the signals in interphase nuclei should be bright and discrete. Scoring the number of signals for each probe in 100 interphase nuclei from each partner is recommended to assess the efficiency of the assay. In this case 2 signals were scored in 95%-99% of nuclei for each probe. Figure 1 shows a metaphase and interphase nucleus from a preparation for a reciprocal translocation between the short arms of chromosomes 5 and 9.
Signals in interphase nuclei from embryo blastomeres should be bright and discrete and scored using separate band pass filters for the colors used. Figure 2 shows a blastomere nucleus with a normal signal pattern (2 copies for all the loci tested) consistent with a normal or balanced chromosome complement for chromosome 5 and 9, and a nucleus with an abnormal signal pattern consistent with an unbalanced product of the translocation that has monosomy (one copy) for the translocated segment of chromosome 5 and trisomy (3 copies) for the translocated segment of chromosome 9.
<img src="/files/ftp_upload/2570/2570fig1.jpg" alt="Figure 1" /> 
Figure 1. A metaphase spread and an interphase nucleus prepared from cultured peripheral blood lymphocytes from a carrier of a reciprocal translocation between the short arms of chromosomes 5 and 9 with breakpoints at 5p14.3 and 9p24.1: 46,XY,t(5;9)(p14.3;p24.1).ish t(5;9)(5ptel48-,9ptel30+;9ptel30-,5ptel48+,9cen+). FISH probes were selected for both translocated segments (5p14.3&rarr;5pter, red Cytocell subtelomere5ptel48 TexasRed ; 9p24.1&rarr;9pter, green Cytocell subtelomere 9ptel30 FITC) and the centric segment of chromosome 9 (9p24.1&rarr;9qter, blue Abbott CEP 9 alpha satellite SpectrumAqua).
<img src="/files/ftp_upload/2570/2570fig2.jpg" alt="Figure 2" /> 
Figure 2. Signals in interphase blastomere nuclei from day-3 embryos captured using a different filter for each fluorochrome and merged to form a composite image. (A) Two signals for each probe indicating two copies of each locus, which is consistent with a normal or balanced complement for the translocation chromosomes. (B) One red signal, three green signals and two blue signals indicating one copy of the translocated segment of chromosome 5, three copies of the translocated segment of chromosome 9 and two copies of the centric segment of chromosome 9, which is consistent with adjacent-1 segregation of the translocation resulting in an unbalanced product with monosomy for 5p14.3&rarr;5pter and trisomy for 9p24.1&rarr;9pter.

<ol>
	<li>Scriven, P. N., Handyside, A. H., Ogilvie, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chromosome+translocations:+segregation+modes+and+strategies+for+preimplantation+genetic+diagnosis.">Chromosome translocations: segregation modes and strategies for preimplantation genetic diagnosis.</a> Prenat. Diagn. 18, 1437-1449 (1998).</li><li>Mackie Ogilvie, C., Scriven, P. N., Harper, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preimplantation+genetic+diagnosis+for+chromosome+rearrangements.">Preimplantation genetic diagnosis for chromosome rearrangements.</a> Preimplantation Genetic Diagnosis. , 194-201 (2009).</li><li>Harper, J. C., Coonen, E., Ramaekers, F. C. S., Delhanty, J. D. A., Handyside, A. H., Winston, R. M. L., Hopman, A. H. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+the+sex+of+human+preimplantation+embryos+in+two+hours+using+an+improved+spreading+method+and+fluorescent+in+situ+hybridisation+using+directly+labelled+probes.">Identification of the sex of human preimplantation embryos in two hours using an improved spreading method and fluorescent in situ hybridisation using directly labelled probes.</a> Hum. Reprod. 9, 721-724 (1994).</li><li>Mackie Ogilvie, C., Scriven, P. N., Harper, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preimplantation+genetic+diagnosis+for+sex-linked+diseases+and+sex-selection+for+non-medical+reasons.">Preimplantation genetic diagnosis for sex-linked diseases and sex-selection for non-medical reasons.</a> Preimplantation Genetic Diagnosis. , 230-235 (2009).</li><li>Munn&#233;, S., Lee, A., Rosenwaks, Z., Grifo, J., Cohen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnosis+of+major+chromosome+aneuploidies+in+human+preimplantation+embryos.">Diagnosis of major chromosome aneuploidies in human preimplantation embryos.</a> Hum. Reprod. 8, 2185-2192 (1993).</li><li>Mackie Ogilvie, C., Scriven, P. N., Harper, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preimplantation+genetic+diagnosis+for+infertility+(preimplantation+genetic+screening).">Preimplantation genetic diagnosis for infertility (preimplantation genetic screening).</a> Preimplantation Genetic Diagnosis. , 203-229 (2009).</li><li>Scriven, P. N., Bossuyt, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnostic+accuracy:+theoretical+models+for+preimplantation+genetic+testing+of+a+single+nucleus+using+the+fluorescence+in+situ+hybridization+technique.+Hum+Reprod.">Diagnostic accuracy: theoretical models for preimplantation genetic testing of a single nucleus using the fluorescence in situ hybridization technique. Hum Reprod.</a> Cytogenetics. 5, 394-400 (2010).</li><li>Coonen, E., Dumoulin, J. C., Ramaekers, F. C., Hopman, A. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimal+preparation+of+preimplantation+embryo+interphase+nuclei+for+analysis+by+fluorescence+in-situ+hybridization.">Optimal preparation of preimplantation embryo interphase nuclei for analysis by fluorescence in-situ hybridization.</a> Hum. Reprod. 9, 533-537 (1994).</li><li>Dozortsev, D. I., McGinnis, K. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+improved+fixation+technique+for+fluorescence+in+situ+hybridization+for+preimplantation+genetic+diagnosis.">An improved fixation technique for fluorescence in situ hybridization for preimplantation genetic diagnosis.</a> Fertil. Steril. 76, 186-188 (2001).</li><li>Hsu, L. Y., Benn, P. A., Tannenbaum, H. L., Perlis, T., Carlson, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chromosomal+polymorphisms+of+1,+9,+16,+and+Y+in+4+major+ethnic+groups:+a+large+prenatal+study.">Chromosomal polymorphisms of 1, 9, 16, and Y in 4 major ethnic groups: a large prenatal study.</a> Am. J. Med. Genet. 26, 95-101 (1987).</li><li>Shim, S. H., Pan, A., Huang, X. L., Tonk, V. S., Varma, S. K., Milunsky, J. M., Wyandt, H. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=FISH+variants+with+D15Z1.">FISH variants with D15Z1.</a> J. Assoc. Genet. Technol. 29, 146-151 (2003).</li><li>Knight, S. J., Flint, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perfect+endings:+a+review+of+subtelomeric+probes+and+their+use+in+clinical+diagnosis.">Perfect endings: a review of subtelomeric probes and their use in clinical diagnosis.</a> J. Med. Genet. 37, 401-409 (2000).</li><li>Thornhill, A. R., de Die-Smulders, C. E., Geraedts, J. P., Harper, J. C., Harton, G. L., Lavery, S. A., Moutou, C., Robinson, M. D., Schmutzler, A. G., Scriven, P. N., Sermon, K. D., Wilton, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ESHRE+PGD+Consortium+(PGS)+ESHRE+PGD+Consortium+'Best+practice+guidelines+for+clinical+preimplantation+genetic+diagnosis+(PGD)+and+preimplantation+genetic+screening+(PGS)'.">ESHRE PGD Consortium (PGS) ESHRE PGD Consortium 'Best practice guidelines for clinical preimplantation genetic diagnosis (PGD) and preimplantation genetic screening (PGS)'.</a> Hum. Reprod. 20, 35-48 (2005).</li><li>Munn&#233;, S., Wells, D., Cohen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Technology+requirements+for+preimplantation+genetic+diagnosis+to+improve+assisted+reproduction+outcomes.">Technology requirements for preimplantation genetic diagnosis to improve assisted reproduction outcomes.</a> Fertil. Steril. 94, 408-430 (2010).</li><li>Wilton, L., Williamson, R., McBain, J., Edgar, D., Voullaire, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Birth+of+a+healthy+infant+after+preimplantation+confirmation+of+euploidy+by+comparative+genomic+hybridization.">Birth of a healthy infant after preimplantation confirmation of euploidy by comparative genomic hybridization.</a> N. Engl. J. Med. 345, 1537-1541 (2001).</li><li>Wells, D., Alfarawati, S., Fragouli, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+comprehensive+chromosomal+screening+for+embryo+assessment:+microarrays+and+CGH.">Use of comprehensive chromosomal screening for embryo assessment: microarrays and CGH.</a> Mol. Hum. Reprod. 14, 703-710 (2008).</li><li>Handyside, A. H., Harton, G. L., Mariani, B., Thornhill, A. R., Affara, N., Shaw, M. A., Griffin, D. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Karyomapping,+a+universal+method+for+genome+wide+analysis+of+genetic+disease+based+on+mapping+crossovers+between+parental+haplotypes.">Karyomapping, a universal method for genome wide analysis of genetic disease based on mapping crossovers between parental haplotypes.</a> J. Med. Genet. 47, 651-658 (2010).</li></ol>

No conflicts of interest declared.

The application of fluorescence in situ hybridization (FISH) to a single embryo cell (blastomere) presents special challenges both in practicalities and in interpretation of the signal pattern. The biopsied cell needs to be spread within a pre-defined area on the slide in order to facilitate its localization following FISH; extreme care needs to be taken in ensuring that the cell is lysed, that the cytoplasm has been dispersed, and that the nucleus is visible and intact; and, as the diagnosis depends on the results from this single cell, stringent scoring and interpretation guidelines should be applied. However, in experienced hands, FISH is a robust technique for pre-implantation genetic diagnosis (PGD) in clinical practice. The principle of PGD by FISH is that target-specific DNA probes labelled with different fluorochromes or haptens can be used to detect the copy number of specific loci, and thereby to detect chromosome imbalance associated with meiotic segregation of chromosome rearrangements (1), including Robertsonian translocations, reciprocal translocations, inversions, and complex rearrangements (2). FISH can also be used to select female embryos in families with X-linked disease, for which there is no mutation-specific test (3, 4). More controversially, FISH has also been used to screen for sporadic chromosome aneuploidy in order to try and improve the efficiency of assisted reproduction (5, 6); however, the predictive value of this test using FSIH is likely to be unacceptably low in most people's hands and it is not recommended for routine clinical use (7). This article concentrates on the technical aspects and the limitations of FISH applied to clinical single-cell diagnosis.
Methods of spreading and fixing single blastomeres include methanol/acetic acid (5, 8), Tween/HCl (9), and a combination of Tween/HCl and methanol/acetic acid (10). Variations include hypotonic treatment of cells prior to spreading and/or pepsin and paraformaldehyde treatment after fixation. The method should be appropriately validated for the laboratory (14). The Tween/HCl method is described in detail in this article. The Tween/HCl method is technically simple and highly reproducible in different laboratories. This method can be used to prepare single nuclei for the FISH diagnosis of sex determination and chromosome rearrangements with acceptable diagnostic accuracy (7).
Probe mixes can combine directly labelled and indirectly labelled probes, and probes from different manufacturers. Probes for known polymorphic chromosome regions (11, 12), or those known to cross-hybridize significantly with other chromosomes (13) should be avoided, although can be used if shown to be specific and suitable for PGD by prior testing on both reproductive partners. Available fluorochromes/haptens and strategies for discriminating probes include the following: Texas Red (TR), fluorescein isothiocyanate (FITC), SpectrumGreen (Vysis), SpectrumOrange (Vysis), SpectrumAqua, biotinylated probes detected with TR-avidin, FITC-avidin, or Cy-5 streptavidin (visualized using a FarRed filter), a mix of red and green probes to produce a yellow signal, a second round of hybridization and a third color created by sequential capturing of SpectrumOrange using a TexasRed and a SpectrumGold filter).
A probe set containing three probes, specific for the centromere regions of the X and Y chromosomes and one autosome, is recommended for sex determination (14); the autosomal probe is used to establish ploidy and thereby to differentiate between trisomy X (2n, 47,XXX) and triploidy (3n, 69,XXX), and between tetrasomy X (48,XXXX) and tetraploidy (4n, 92,XXXX). A typical probe set applied in this setting is the Abbott AneuVysion mix containing alpha-satellite X, Y, and 18; this probe set has been demonstrated to have a very low polymorphism rate, and therefore pre-treatment work-up of the reproductive partners is not required (14).
The probe mix for any specific rearrangement should: Ideally contain probes at least sufficient to detect all the expected products of the rearrangement with chromosome imbalance. If this is not possible, probe mixes where the undetected unbalanced products have been assessed to be non-viable in a recognizable pregnancy and are likely to have very low prevalence may be acceptable (14). Be tested on cultured lymphocyte metaphases from both reproductive partners. At least ten metaphase spreads should be examined for probe specificity, polymorphisms and cross-hybridization, and, for the chromosome rearrangement carrier, to ensure that the probes hybridize as expected to the different segments of the rearrangement. In addition, at least 100 interphase nuclei from these preparations should be scored to assess signal specificity, brightness, and discreteness (14).
Commercial PGS probe sets are available (e.g. Abbott MultiVysion PB or PGT), targeting the chromosomes most frequently found to be aneuploid in products of conception, and comprising a single probe per chromosome targeted. Typically the nucleus may have a second hybridization with probes for additional chromosomes providing an assay for chromosomes 13, 15, 16, 18, 21, 22, and XY (14). The predictive value of this test using the spreading and FISH technique described here is likely to be unacceptably low in most people's hands and it is not recommended for routine clinical use (7, 15).
Techniques such as comparative genomic hybridization (CGH) applied to single cells are able to test for the copy number of every chromosome (Wilton et al. 2001), and the use of single nucleotide polymorphisms (SNP) arrays and quantitative analysis (Wells et al. 2008) or "karyomapping" genotyping (Handyside et al. 2009) are promising alternative techniques to detect chromosome aneuploidy. However, the resolution limit and accuracy for segment imbalance remain uncertain and it is likely that FISH will continue to be the technique of choice for chromosome rearrangements involving small segments.

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<tr>
<td>Hydrochloric Acid, 2.5L</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>101254H</td>
<td>&nbsp;</td>
<tr>
<td>Sodium Chloride, 5Kg</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>443827W</td>
<td>&nbsp;</td>
<tr>
<td>Potassium Chloride, 250g</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>26764.232</td>
<td>&nbsp;</td>
<tr>
<td>di-Sodium Hydrogen Orthophosphate Anhydrous, 500g</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>102494C</td>
<td>&nbsp;</td>
<tr>
<td>Potassium Dihydrogen Orthophosphate, 500g</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>10203 4B</td>
<td>&nbsp;</td>
<tr>
<td>Sodium Hydroxide Pellets, 500g</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>28245.265</td>
<td>&nbsp;</td>
<tr>
<td>Tween20, 500mL</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>663684B</td>
<td>&nbsp;</td>
<tr>
<td>Ethanol, 2.5L</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>8.18760.2500</td>
<td>Duty Paid</td>
</tr>
<tr>
<td>Tri-Sodium Citrate, 5Kg</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>27833.363</td>
<td>&nbsp;</td>
<tr>
<td>Cow Gum, 250mL</td>
<td>&nbsp;</td>
<td>Cow Proofings Ltd.</td>
<td>No longer available</td>
<td>Old stocks can still be found in art shops</td>
</tr>
<tr>
<td>DAPI/Antifade ES, 0.125&mu;g/mL, 500ul</td>
<td>&nbsp;</td>
<td>Cytocell</td>
<td>DES500L</td>
<td>150&mu;l vial rec&#x2019;d with each Cytocell TEL Probe</td>
</tr>
<tr>
<td>Nail Varnish, 12mL</td>
<td>&nbsp;</td>
<td>Boots</td>
<td>10088316001</td>
<td>&nbsp;</td>
<tr>
<td>Amine-coated Slides, 25</td>
<td>&nbsp;</td>
<td>Genetix</td>
<td>K2615</td>
<td>&nbsp;</td>
<tr>
<td>DAPI, 0.1mL</td>
<td>&nbsp;</td>
<td>Sigma-Aldrich</td>
<td>D-9542</td>
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<td>Vectashield, 10mL</td>
<td>&nbsp;</td>
<td>Vector Laboratories</td>
<td>H1000</td>
<td>&nbsp;</td>
<tr>
<td>Texas-Red-avidin, 0.001mL</td>
<td>&nbsp;</td>
<td>Vector Laboratories</td>
<td>A-2016</td>
<td>&nbsp;</td>
<tr>
<td>FITC-avidin, 0.001mL</td>
<td>&nbsp;</td>
<td>Vector Laboratories</td>
<td>A-2011</td>
<td>&nbsp;</td>
<tr>
<td>Cy-5 Streptavidin, 0.001mL</td>
<td>&nbsp;</td>
<td>GE Healthcare</td>
<td>PA45001</td>
<td>&nbsp;</td>
<tr>
<td>Microcentrifuge Tubes, 1.75mL, box of 500</td>
<td>&nbsp;</td>
<td>Thistle Scientific</td>
<td>AX-MCT-175-C</td>
<td>&nbsp;</td>
<tr>
<td>Microcentrifuge Tubes, 0.6mL, box of 1000</td>
<td>&nbsp;</td>
<td>Thistle Scientific</td>
<td>AX-MCT-060-C-CS</td>
<td>&nbsp;</td>
<tr>
<td>30ml Universal Containers, box of 400</td>
<td>&nbsp;</td>
<td>Sterilin</td>
<td>128B</td>
<td>Available from NHS Supply Chain, Cat No. KCP053</td>
</tr>
<tr>
<td>Hot Block</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Spirit Burner Spirit Burner Socket Spirit Burner Wick</td>
<td>&nbsp;</td>
<td>VWR VWR VWR</td>
<td>451-0107 451-3112 451-3111</td>
<td>&nbsp;</td>
<tr>
<td>Plugged Glass Pipettes</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>PMK-300-052R</td>
<td>&nbsp;</td>
<tr>
<td>Dissecting Microscope</td>
<td>&nbsp;</td>
<td>Wild Heerbrugg</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Tissues, 100boxes</td>
<td>&nbsp;</td>
<td>NHS SUPPLY CHAIN</td>
<td>MJT058</td>
<td>&nbsp;</td>
<tr>
<td>Metal Culture Trays</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Plastic Melamine Trays</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>682-009</td>
<td>&nbsp;</td>
<tr>
<td>Oven</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Mouth Pipette Mouthpiece</td>
<td>&nbsp;</td>
<td>Scientific Laboratory Supplies</td>
<td>HAE3700 </td>
<td>&nbsp;</td>
<tr>
<td>Tubing</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Syringe Filter, 0.2&mu;m pore size, 25mm diameter</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>FDM-340-010U</td>
<td>&nbsp;</td>
<tr>
<td>Diamond Pen</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>818-0021</td>
<td>&nbsp;</td>
<tr>
<td>Hot Block for Slides</td>
<td>&nbsp;</td>
<td>Thermo Hybaid</td>
<td>HBOSBB</td>
<td>&nbsp;</td>
<tr>
<td>Hybridization Chamber</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Tissue Roll</td>
<td>&nbsp;</td>
<td>NHS SUPPLY CHAIN</td>
<td>MJT004</td>
<td>&nbsp;</td>
<tr>
<td>Schieferdecker Jar</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>631-9313</td>
<td>&nbsp;</td>
<tr>
<td>Coplin Jar</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>631-9331</td>
<td>&nbsp;</td>
<tr>
<td>Forceps, Fine</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>232-2123</td>
<td>&nbsp;</td>
<tr>
<td>Forceps, Blunt</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>232-2113</td>
<td>&nbsp;</td>
<tr>
<td>1000mL Beaker</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>213-1642</td>
<td>&nbsp;</td>
<tr>
<td>Phase Contrast Microscope</td>
<td>&nbsp;</td>
<td>Nikon</td>
<td>E200</td>
<td>&nbsp;</td>
<tr>
<td>Fibre-free Blotting Cards, box of 100</td>
<td>&nbsp;</td>
<td>Fisher Scientific (Raymond Lamb)</td>
<td>SDE1</td>
<td>&nbsp;</td>
<tr>
<td>Blue-Frosted Microscope Slides, box of 100</td>
<td>&nbsp;</td>
<td>Scientific Laboratory Supplies</td>
<td>MIC3022</td>
<td>&nbsp;</td>
<tr>
<td>Coverslips, 18x18mm, No. 1, box of 200</td>
<td>&nbsp;</td>
<td>Scientific Laboratory Supplies</td>
<td>MIC3110</td>
<td>&nbsp;</td>
<tr>
<td> Coverslips, 22x22mm, No. 0, box of 200</td>
<td>&nbsp;</td>
<td>Scientific Laboratory Supplies</td>
<td>MIC3104</td>
<td>&nbsp;</td>
<tr>
<td>Coverslips, 22x50mm, No. 0, box of 100</td>
<td>&nbsp;</td>
<td>Scientific Laboratory Supplies</td>
<td>MIC3206</td>
<td>&nbsp;</td>
<tr>
<td>1mL Syringe, box of 100</td>
<td>&nbsp;</td>
<td>NHS Supply Chain</td>
<td>FWC045</td>
<td>&nbsp;</td>
<tr>
<td>1mL Pipette Tip, 10racks of 1000</td>
<td>&nbsp;</td>
<td>Thistle Scientific</td>
<td>AX-T-1000-C-L-R</td>
<td>&nbsp;</td>
<tr>
<td>Incubator</td>
<td>&nbsp;</td>
<td>LEEC</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Waterbath</td>
<td>&nbsp;</td>
<td>Grant</td>
<td>W22</td>
<td>&nbsp;</td>
<tr>
<td>Alcohol Thermometer</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>Various sources available</td>
</tr>
<tr>
<td>pH Meter</td>
<td>&nbsp;</td>
<td>Jenway</td>
<td>3305</td>
<td>&nbsp;</td>
<tr>
<td>pH Electrode</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>662-1759</td>
<td>BNC Plug to fit Jenway pH meter 3305</td>
</tr>
<tr>
<td>Heated Stirrer</td>
<td>&nbsp;</td>
<td>Bibby</td>
<td>HC502</td>
<td>&nbsp;</td>
<tr>
<td>1mL Pasteur Pipettes, box of 500</td>
<td>&nbsp;</td>
<td>Scientific Laboratory Supplies</td>
<td>PIP4202</td>
<td>&nbsp;</td>
<tr>
<td>Parafilm, 50mm x 75m</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>291-1214</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>

fish for pre-implantation genetic diagnosis

Pre-implantation genetic diagnosis (PGD) is an established alternative to pre-natal diagnosis, and involves selecting pre-implantation embryos from a cohort generated by assisted reproduction technology (ART). This selection may be required because of familial monogenic disease (e.g. cystic fibrosis), or because one partner carries a chromosome rearrangement (e.g. a two-way reciprocal translocation). PGD is available for couples who have had previous affected children, and/or in the case of chromosome rearrangements, recurrent miscarriages, or infertility. Oocytes aspirated following ovarian stimulation are fertilized by in vitro immersion in semen (IVF) or by intracytoplasmic injection of an individual spermatozoon (ICSI). Pre-implantation cleavage-stage embryos are biopsied, usually by the removal of a single cell on day 3 post-fertilization, and the biopsied cell is tested to establish the genetic status of the embryo. Fluorescence in situ hybridization (FISH) on the fixed nuclei of biopsied cells with target-specific DNA probes is the technique of choice to detect chromosome imbalance associated with chromosome rearrangements, and to select female embryos in families with X-linked disease for which there is no mutation-specific test. FISH has also been used to screen embryos for spontaneous chromosome aneuploidy (also known as PGS or PGD-AS) in order to try and improve the efficiency of assisted reproduction; however, the predictive value of this test using the spreading and FISH technique described here is likely to be unacceptably low in most people's hands and it is not recommended for routine clinical use. We describe the selection of suitable probes for single-cell FISH, spreading techniques for blastomere nuclei, and in situ hybridization and signal scoring, applied to PGD in a clinical setting.

Watch this Scientific Journal Video about FISH for Pre-implantation Genetic Diagnosis at JoVE.com

FISH for Pre-implantation Genetic Diagnosis

This article describes the selection of suitable probes for single-cell FISH, spreading techniques for blastomere nuclei, and in situ hybridization and signal scoring, applied to pre-implantation genetic diagnosis (PGD) in a clinical setting.

Pre-implantation genetic diagnosis (PGD) is an established alternative to pre-natal diagnosis, and involves selecting pre-implantation embryos from a ...

fish-for-pre-implantation-genetic-diagnosis

Research

JoVE Journal

Medicine

Gene Transfer for Ischemic Heart Failure in a Preclinical Model

Various emerging technologies are being developed for patients with heart failure. Well-established preclinical evaluations are necessary to determine their efficacy and safety.
Gene therapy using viral vectors is one of the most promising approaches for treating cardiac diseases. Viral delivery of various different genes by changing the carrier gene has immeasurable therapeutic potential.
In this video, the full process of an animal model of heart failure creation followed by gene transfer is presented using a swine model. First, myocardial infarction is created by occluding the proximal left anterior descending coronary artery. Heart remodeling results in chronic heart failure. Unique to our model is a fairly large scar which truly reflects patients with severe heart failure who require aggressive therapy for positive outcomes. After myocardial infarct creation and development of scar tissue, an intracoronary injection of virus is demonstrated with simultaneous nitroglycerine infusion. Our injection method provides simple and efficient gene transfer with enhanced gene expression. This combination of a myocardial infarct swine model with intracoronary virus delivery has proven to be a consistent and reproducible methodology, which helps not only to test the effect of individual gene, but also compare the efficacy of many genes as therapeutic candidates.

A method of gene transfer for the treatment of ischemic heart failure is described using a swine model of myocardial infarction. Our simple and reproducible method enables us to readily evaluate the efficacy of various gene transfers with a very simple and reproducible way.

Various emerging technologies are being developed for patients with heart failure. Well-established preclinical evaluations are necessary to determine ...

Transabdominal Ultrasound for Pregnancy Diagnosis in Reeves' Muntjac Deer

Reeves' muntjac deer (Muntiacus reevesi) are a small cervid species native to southeast Asia, and are currently being investigated as a potential model of prion disease transmission and pathogenesis. Vertical transmission is an area of interest among researchers studying infectious diseases, including prion disease, and these investigations require efficient methods for evaluating the effects of maternal infection on reproductive performance. Ultrasonographic examination is a well-established tool for diagnosing pregnancy and assessing fetal health in many animal species1-7, including several species of farmed cervids8-19, however this technique has not been described in Reeves' muntjac deer. Here we describe the application of transabdominal ultrasound to detect pregnancy in muntjac does and to evaluate fetal growth and development throughout the gestational period. Using this procedure, pregnant animals were identified as early as 35 days following doe-buck pairing and this was an effective means to safely monitor the pregnancy at regular intervals. Future goals of this work will include establishing normal fetal measurement references for estimation of gestational age, determining sensitivity and specificity of the technique for diagnosing pregnancy at various stages of gestation, and identifying variations in fetal growth and development under different experimental conditions.

Transabdominal Ultrasound for Pregnancy Diagnosis in Reeves&#039; Muntjac Deer

Transabdominal ultrasound is described as an effective, noninvasive means for assessing reproductive status in Reeves' muntjac deer. These methods can be used to achieve early pregnancy diagnosis and to evaluate fetal viability. Future applications of this technique include estimation of gestational age and effects of maternal disease on fetal development.

Reeves' muntjac deer (Muntiacus reevesi) are a small cervid species native to southeast Asia, and are currently being investigated as a potential model of ...

Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination

Common foot and ankle pathologies have been linked to isolated Musculus gastrocnemius tightness (MGT). Various examination techniques have been described to assess MGT. Still, a standardized examination procedure is missing. Literature argues for weightbearing examination but the degree of knee flexion needed to eliminate the restraining effect of the M. gastrocnemius on ankle dorsiflexion (ADF) is unknown. This manuscript investigates the effect of knee flexion on ankle dorsiflexion and provides a detailed description of a standardized examination protocol. Examination on 20 healthy individuals revealed, that 20&#176; of knee flexion is sufficient to fully eliminate the influence of the M. gastrocnemius on ADF. This builds the prerequisite for a standardized examination for MGT. Non-weightbearing and weightbearing examination of ADF has to be conducted with the knee fully extended and at least 20&#176; flexed. Two investigators should conduct non-weightbearing testing with the subject in supine position. In order to obtain reliable results, the axis of the fibula should be marked. One examiner can conduct weightbearing examination with the subject in lunge stance. Isolated MGT is present if ADF is impaired with the knee fully extended and knee flexion results in a significant ADF increase. The herein presented standardized examination is the prerequisite for future studies aiming at establishing norm values.

Diagnosis of Musculus Gastrocnemius Tightness - Key Factors for the Clinical Examination

Isolated Musculus gastrocnemius tightness is a common cause for foot and ankle pathologies. Currently no standardized examination procedure exists. This manuscript demonstrates that 20 degree of knee flexion eliminates the restraining effect of the M. gastrocnemius on ankle dorsiflexion and presents a video description of a standardized examination protocol.

Common foot and ankle pathologies have been linked to isolated Musculus gastrocnemius tightness (MGT). Various examination techniques have been described ...

Induction of Accelerated Atherosclerosis in Mice: The "Wire-Injury" Model

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. Moreover, by rupture of the defective vascular wall, atherosclerosis induces occlusive thrombus formation, which represents the main cause of myocardial infarction or stroke and the most frequent cause of death. Despite the advances in the cardiovascular field, many questions remain unanswered, and additional basic research is essential to improve our understanding of the molecular mechanisms during atherosclerosis and its effects. Due to limited clinical studies, there is a need for representative animal models recreating atherosclerotic conditions such as neointima formation after stent implantation, balloon angioplasty, or endarterectomy. Since the mouse presents many advantages and is the most frequently used model for studying molecular processes, the current study proposes an invasive procedure of endothelial denudation, also known as the wire-injury model, which is representative of the human condition of neointima formation in arteries after revascularization procedures.

Induction of Accelerated Atherosclerosis in Mice: The &quot;Wire-Injury&quot; Model

This study describes an invasive procedure for the induction of accelerated atherosclerosis in mice. In comparison to other methods using electric- or cryo-induced injury, mechanical-induced injury mimics the human condition of restenosis after revascularization therapies and is ideal for the study of the molecular mechanisms involved.

Atherosclerosis is a proliferative fibro-inflammatory disease developing in the arterial wall, inducing a deficient blood flow or a lack of blood flow. ...

Hydra, a Computer-Based Platform for Aiding Clinicians in Cardiovascular Analysis and Diagnosis

Cardiovascular diseases (CVDs) are the leading cause of death throughout the world. The total risk of developing CVD is determined by the combined effect of different cardiovascular risk factors (e.g., diabetes, raised blood pressure, unhealthy diet, tobacco use, stress, etc.) that commonly coexist and act multiplicatively. Most CVDs can be prevented by an early identification of the highest risk factors and an appropriate treatment. The stratification of cardiovascular risk factors involves a wide range of parameters and tests that specialists use in their clinical practice. In addition to cardiovascular (CV) risk stratification, ambulatory blood pressure monitoring (ABPM) also provides relevant information for diagnostic and treatment purposes. This work presents a list of protocols based on the Hydra platform, a web-based system for clinical decision support which incorporates a set of functionalities and services that are required for complete cardiovascular analysis, risk assessment, early diagnosis, treatment and monitoring of patients over time. The program includes tools for inputting and managing comprehensive patient data, organized into different checkups to track the evolution over time. It also has a risk stratification tool to compute a CV risk factor based upon several risk stratification tables of reference. Additionally, the program includes a tool that incorporates ABPM analysis and allows the extraction of valuable information by monitoring blood pressure over a specific period of time. Finally, the reporting service summarizes the most relevant information in a set of reports that aid clinicians in their clinical decision-making process.

This article presents a protocol based on Hydra &#8212; a web-based system for clinical decision support that integrates a full and detailed set of functionalities and services required by physicians for complete cardiovascular analysis, risk assessment, early diagnosis, treatment, and monitoring over time.

Cardiovascular diseases (CVDs) are the leading cause of death throughout the world. The total risk of developing CVD is determined by the combined effect ...

International Expert Consensus and Recommendations for Neonatal Pneumothorax Ultrasound Diagnosis and Ultrasound-guided Thoracentesis Procedure

Pneumothorax (PTX) represents accumulation of the air in the pleural space. A large or tension pneumothorax can collapse the lung and cause hemodynamic compromise, a life-threatening disorder. Traditionally, neonatal pneumothorax diagnosis has been based on clinical images, auscultation, transillumination, and chest X-ray findings. This approach may potentially lead to a delay in both diagnosis and treatment. The use of lung US in diagnosis of PTX together with US-guided thoracentesis results in earlier and more precise management. The recommendations presented in this publication are aimed at improving the application of lung US in guiding neonatal PTX diagnosis and management.

Pneumothorax is a common emergency and critical disease in newborn infants that needs rapid, clear diagnosis and timely treatment. Diagnosis and treatment based on chest X-rays are associated with delayed management and radiation damage. Lung ultrasound (US) provides useful guidance for rapid, accurate diagnosis and the precise thoracentesis of pneumothorax.

Pneumothorax (PTX) represents accumulation of the air in the pleural space. A large or tension pneumothorax can collapse the lung and cause hemodynamic ...

Diagnosis and Surgical Treatment of Human Brucellar Spondylodiscitis

Brucellar spondylodiscitis (BS) is the most prevalent and significant osteoarticular presentation of human Brucellosis, which is commonly manifested in pastoral communities. It is difficult to differentially diagnose and usually leads to irreversible neurologic deficits and spinal deformities. The initial diagnosis of BS is based on clinical findings and radiographic assessments, and the confirmed diagnosis should be established by the isolation of Brucella species from the blood and/or the standard tube agglutination test. Differential diagnosis of multifocal BS from either degenerative disc diseases or tuberculosis is especially highlighted. The surgical approach, either endoscopic or open, is demonstrated in detail, accompanied by radiographic evidence of structural compression or severe instability. Further, the crucial surgical steps, including single-stage transforaminal decompression, debridement, interbody fusion, and internal fixation, are explained. Moreover, perioperative care and postoperative rehabilitation are also addressed. Taken together, this clinical algorithm presents a practical guide that has yielded substantially satisfactory outcomes in the past decades, which can also be introduced for large-scale application to manage human BS, especially in endemic regions.

We describe a clinical algorithm, based on decades of front-line experience of diagnosis and surgical treatment of human Brucellar spondylodiscitis in the largest medical center of the China's Xinjiang Pastoral Area.

Brucellar spondylodiscitis (BS) is the most prevalent and significant osteoarticular presentation of human Brucellosis, which is commonly manifested in ...

Testing Acetylcholine Followed by Adenosine for Invasive Diagnosis of Coronary Vasomotor Disorders

More than 50% of patients with signs and symptoms of myocardial ischemia undergoing coronary angiography have unobstructed coronary arteries. Coronary vasomotor disorders (impaired vasodilatation and/or enhanced vasoconstriction/spasm) represent important functional causes for such a clinical presentation. Although impaired vasodilatation may be assessed with non-invasive techniques such as positron emission tomography or cardiac magnetic resonance imaging, there is currently no reliable non-invasive technique for the diagnosis of coronary spasm available. Thus, invasive diagnostic procedures (IDP) have been developed for the diagnosis of coronary vasomotor disorders including spasm testing as well as assessment of coronary vasodilatation. The identification of the underlying type of disorder (so called endotype) allows the initiation of targeted pharmacological treatments. Despite the fact that such an approach is recommended by the current European Society of Cardiology guidelines for the management of chronic coronary syndromes based on the CorMicA study, comparability of results as well as multicenter trials are currently hampered by major differences in institutional protocols for coronary functional testing. This article describes a comprehensive IDP protocol including intracoronary acetylcholine provocation testing for diagnosis of epicardial/microvascular spasm, followed by Doppler wire-based assessment of coronary flow reserve (CFR) and hyperemic microvascular resistance (HMR) in search of coronary vasodilatory impairment.

Coronary vasomotion disorders represent frequent functional causes of angina in patients with unobstructed coronaries. The underlying mechanism of angina (endotype) in these patients can be determined by a comprehensive invasive diagnostic procedure based on acetylcholine provocation testing followed by Doppler-derived assessment of the coronary flow reserve and microvascular resistance.

More than 50% of patients with signs and symptoms of myocardial ischemia undergoing coronary angiography have unobstructed coronary arteries. Coronary ...

Measurement of Myocardial Lactate Production for Diagnosis of Coronary Microvascular Spasm

In about a quarter of patients with angina and non-obstructive coronary arteries, no epicardial spasm is noted on coronary arteriography during an angina attack. Since the pressure-rate product is almost identical at rest and the onset of attack in those patients, the decrease in coronary blood flow rather than increased myocardial oxygen consumption is likely to explain myocardial ischemia, indicating a substantial involvement with coronary microvascular spasm (MVS). Myocardial lactate production, which could be defined as a negative myocardial lactate extraction ratio (ratio of the coronary arterial-venous difference in lactate concentration to arterial concentration), is considered indicative of objective evidence to support the emerging myocardial ischemia. Thus, monitoring of the myocardial lactate production and the emergence of chest pain and ischemic electrocardiographic changes during acetylcholine (ACh) provocation testing is of significant value for detecting the entity of MVS. Practically, 1 min after incremental doses of ACh (20, 50, and 100 &#956;g) are administered into the left coronary artery (LCA), paired samples of 1 mL of blood are collected from the LCA ostium and coronary sinus for measurement of lactate concentration by a calibrated automatic lactate analyzer. Then, the development of MVS could be confirmed by negative myocardial lactate extraction ratio despite the absence of angiographically demonstrable epicardial coronary spasm or before its occurrence throughout ACh provocation testing. In conclusion, assessment of myocardial lactate production is essential and valuable for the diagnosis of MVS.

Myocardial lactate production (coronary arterial-venous difference in serum lactate level) during coronary spasm provocation testing is considered as a highly sensitive marker that reflects acetylcholine-induced myocardial ischemia due to microvascular spasm. This article presents the procedures to assess myocardial lactate production for the diagnosis of coronary microvascular spasm.

In about a quarter of patients with angina and non-obstructive coronary arteries, no epicardial spasm is noted on coronary arteriography during an angina ...

Basophil Activation Test for Allergy Diagnosis

The basophil activation test (BAT) is a complementary in vitro diagnostic test that can be used in addition to clinical history, skin test (ST), and specific IgE (sIgE) determination in the evaluation of IgE-mediated allergic reactions to food, insect venom, drugs, as well as some forms of chronic urticaria. However, the role of this technique in the diagnostic algorithms is highly variable and not well determined.
BAT is based on the determination of basophil response to allergen/drug cross-linking IgE activation through the measurement of activation markers (such as CD63, CD203c) by flow cytometry. This test can be a useful and complementary tool to avoid controlled challenge tests&#160;to confirm allergy diagnosis, especially in subjects experiencing severe life-threatening reactions. In general, the performance of BAT should be considered if i) the allergen/drug produces false positive results in ST; ii) there is no allergen/drug source to use for ST or sIgE determination; iii) there is discordance between patient history and ST or sIgE determination; iv) symptoms suggest that ST may result in systemic response; v) before considering a CCT to confirm the culprit allergen/drug. The main limitations of the test are related to non-optimal sensitivity, especially in drug allergy, the need to perform the test no longer than 24 h after sample extraction, and the lack of standardization between laboratories in terms of procedures, concentrations, and cell markers.

The basophil activation test is a complementary in vitro diagnostic test for the evaluation of IgE-mediated allergic reactions based on the detection of basophil activation in the presence of a specific stimulus through the measure of activation markers by flow cytometry.

The basophil activation test (BAT) is a complementary in vitro diagnostic test that can be used in addition to clinical history, skin test (ST), and ...