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Objective: To evaluate the diagnostic performance of the BACs-on-Beads(™) (BoBs(™)) assay for prenatal detection of chromosomal abnormalities.Design: Retrospective study.Setting: Tertiary prenatal diagnosis centre.Population: Women referred for prenatal diagnosis.Methods: We retrieved 2153 archived DNA samples collected between January 2010 and August 2011 for the BoBs(™) assay. These samples had previously been tested by quantitative fluorescence polymerase chain reaction (QF-PCR) and karyotyping. In the BoBs(™) assay a sample was defined as normal disomic when the ratio of the fluorescence intensities in a chromosome locus lay within the threshold (mean ratio ± 2SD), and as deleted or duplicated when the ratio was below the lower threshold (0.6-0.8) or above the upper threshold (1.3-1.4), respectively. The BoBs(™) results were further validated by microarray and compared in a blinded manner with the original QF-PCR and karyotyping results.Main Outcome Measures: Concordance of any numerical, structural, and submicroscopic chromosomal abnormalities between the methods.Results: BACs-on-Beads(™) was similar to karyotyping and QF-PCR in detecting trisomy 13, trisomy 18, trisomy 21, and sex chromosomal aneuploidies, and superior to QF-PCR in detecting major structural abnormalities (53.3 versus 13.3%) and mosaicism (28.6 versus 0%) involving chromosomal abnormalities other than the common aneuploidies. BoBs(™) detected six microdeletion syndromes missed by karyotyping and QF-PCR; however, BoBs(™) missed two cases of triploidy identified by QF-PCR. Therefore, the sensitivity of BoBs(™) is 96.7% (95% CI 92.6-98.7%), and its specificity is 100% (95% CI 99.8-100%).Conclusions: BACs-on-Beads(™) can replace QF-PCR for triaging in prenatal diagnosis, and gives a better diagnostic yield than current rapid aneuploidy tests. [ABSTRACT FROM AUTHOR]

Objective To evaluate the diagnostic performance of the BACs-on-Beads™ (BoBs™) assay for prenatal detection of chromosomal abnormalities. Design Retrospective study. Setting Tertiary prenatal diagnosis centre. Population Women referred for prenatal diagnosis. Methods We retrieved 2153 archived DNA samples collected between January 2010 and August 2011 for the BoBs™ assay. These samples had previously been tested by quantitative fluorescence polymerase chain reaction ( QF- PCR) and karyotyping. In the BoBs™ assay a sample was defined as normal disomic when the ratio of the fluorescence intensities in a chromosome locus lay within the threshold (mean ratio ± 2 SD), and as deleted or duplicated when the ratio was below the lower threshold (0.6-0.8) or above the upper threshold (1.3-1.4), respectively. The BoBs™ results were further validated by microarray and compared in a blinded manner with the original QF- PCR and karyotyping results. Main outcome measures Concordance of any numerical, structural, and submicroscopic chromosomal abnormalities between the methods. Results BACs-on-Beads™ was similar to karyotyping and QF- PCR in detecting trisomy 13, trisomy 18, trisomy 21, and sex chromosomal aneuploidies, and superior to QF- PCR in detecting major structural abnormalities (53.3 versus 13.3%) and mosaicism (28.6 versus 0%) involving chromosomal abnormalities other than the common aneuploidies. BoBs™ detected six microdeletion syndromes missed by karyotyping and QF- PCR; however, BoBs™ missed two cases of triploidy identified by QF- PCR. Therefore, the sensitivity of BoBs™ is 96.7% (95% CI 92.6-98.7%), and its specificity is 100% (95% CI 99.8-100%). Conclusions BACs-on-Beads™ can replace QF- PCR for triaging in prenatal diagnosis, and gives a better diagnostic yield than current rapid aneuploidy tests. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The objective of the study was to evaluate the ability of a new prenatal diagnostic platform - prenatal BACs-on-Beads[TM] (BoBs[TM]) in detecting mosaicism by comparison to quantitative fluorescence-polymerase chain reaction (QF-PCR). METHODS: A validation study of prenatal BoBs[TM] was firstly performed using 18 artificially constructing mosaic samples involving various aneuploidies and microdeletion conditions. Additionally, we compared the accuracy between prenatal BoBs[TM] and QF-PCR for 18 archived clinical mosaic cases and nine chromosomally abnormal cell lines with reference to conventional karyotype results. RESULTS: In the validation study, BoBs[TM] allowed the detection of mosaicism at a level of 20-40%. Among the clinical mosaic cases, 14/18 cases were within the detection of BoBs[TM], 8/14 (57.1%) could be identified by BoBs[TM] and 6/9 (66.7%) by QF-PCR, but 6/14 (42.9%) were missed by both tests. Three cases (16.7%) were detected by prenatal BoBs[TM] but missed by QF-PCR, whereas QF-PCR detected one case that was missed by BoBs[TM]. The overall sensitivity of BoBs[TM] in detecting mosaicism is 44.4% (8/18), which is slightly higher than that of QF-PCR (33.3%; 6/18). CONCLUSION: Prenatal BoBs[TM] has a sensitivity of 57.1% in the detection clinical mosaic cases. According to the validation test, mosaicism of 20% or greater is detectable by the BoBs[TM] assay. © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Previous cross-cultural eye-tracking studies examining face recognition discovered differences in the eye movement strategies that observers employ when perceiving faces. However, it is unclear (1) the degree to which this effect is fundamentally related to culture and (2) to what extent facial physiognomy can account for the differences in looking strategies when scanning own- and other-race faces. In the current study, Malay, Chinese and Indian young adults who live in the same multiracial country performed a modified yes/no recognition task. Participants' recognition accuracy and eye movements were recorded while viewing muted face videos of own- and other-race individuals. Behavioural results revealed a clear own-race advantage in recognition memory, and eye-tracking results showed that the three ethnic race groups adopted dissimilar fixation patterns when perceiving faces. Chinese participants preferentially attended more to the eyes than Indian participants did, while Indian participants made more and longer fixations on the nose than Malay participants did. In addition, we detected statistically significant, though subtle, differences in fixation patterns between the faces of the three races. These findings suggest that the racial differences in face-scanning patterns may be attributed both to culture and to variations in facial physiognomy between races., (© 2023 The British Psychological Society.)

Objective: To evaluate the diagnostic performance of the BACs-on-Beads(™) (BoBs(™)) assay for prenatal detection of chromosomal abnormalities., Design: Retrospective study., Setting: Tertiary prenatal diagnosis centre., Population: Women referred for prenatal diagnosis., Methods: We retrieved 2153 archived DNA samples collected between January 2010 and August 2011 for the BoBs(™) assay. These samples had previously been tested by quantitative fluorescence polymerase chain reaction (QF-PCR) and karyotyping. In the BoBs(™) assay a sample was defined as normal disomic when the ratio of the fluorescence intensities in a chromosome locus lay within the threshold (mean ratio ± 2SD), and as deleted or duplicated when the ratio was below the lower threshold (0.6-0.8) or above the upper threshold (1.3-1.4), respectively. The BoBs(™) results were further validated by microarray and compared in a blinded manner with the original QF-PCR and karyotyping results., Main Outcome Measures: Concordance of any numerical, structural, and submicroscopic chromosomal abnormalities between the methods., Results: BACs-on-Beads(™) was similar to karyotyping and QF-PCR in detecting trisomy 13, trisomy 18, trisomy 21, and sex chromosomal aneuploidies, and superior to QF-PCR in detecting major structural abnormalities (53.3 versus 13.3%) and mosaicism (28.6 versus 0%) involving chromosomal abnormalities other than the common aneuploidies. BoBs(™) detected six microdeletion syndromes missed by karyotyping and QF-PCR; however, BoBs(™) missed two cases of triploidy identified by QF-PCR. Therefore, the sensitivity of BoBs(™) is 96.7% (95% CI 92.6-98.7%), and its specificity is 100% (95% CI 99.8-100%)., Conclusions: BACs-on-Beads(™) can replace QF-PCR for triaging in prenatal diagnosis, and gives a better diagnostic yield than current rapid aneuploidy tests., (© 2014 Royal College of Obstetricians and Gynaecologists.)

Cutaneous T-cell lymphomas (CTCL) are a heterogeneous group of malignancies derived from skin-homing T cells. The most common forms of CTCL are Mycosis Fungoides (MF) and Sezary Syndrome (SS). Accurate diagnosis remains a challenge due to the heterogeneity of presentation and the lack of highly characteristic immunophenotypical and genetic markers. Over the past decade molecular studies have improved our understanding of the biology of CTCL. The identification of gene expression differences between normal and malignant T-cells has led to promising new diagnostic and prognostic biomarkers that now need validation to be incorporated into clinical practice. These biomarkers may also provide insight into the mechanism of development of CTCL. Additionally, treatment options have expanded with the approval of new agents, such as histone deacetylase inhibitors. A better understanding of the cell biology, immunology and genetics underlying the development and progression of CTCL will allow the design of more rational treatment strategies for these malignancies. This review summarizes the clinical epidemiology, staging and natural history of MF and SS; discusses the immunopathogenesis of MF and the functional role of the malignant T-cells; and reviews the latest advances in MF and SS treatment., (© 2011 Blackwell Publishing Ltd.)

Objective: T cells from patients with systemic lupus erythematosus (SLE) display antigen receptor-mediated signaling aberrations associated with defective T cell receptor (TCR) zeta chain protein and messenger RNA (mRNA) expression. This study was undertaken to explore the possibility that coding-region mutations/polymorphisms of the TCR zeta chain could account for its decreased expression and altered signaling in SLE T cells., Methods: TCR zeta chain mRNA from 48 SLE patients, 18 disease controls, and 21 healthy volunteers was reverse transcribed, amplified by polymerase chain reaction, and cloned, and complementary DNA (cDNA) was sequenced. DNA sequences from multiple clones were analyzed for silent single-nucleotide polymorphisms, mutations, and splice variations, to promote the identification of heterozygosity., Results: DNA sequence analysis revealed several widely distributed missense mutations and silent polymorphisms in the coding region of the TCR zeta chain, which were more frequent in SLE patients than in patients with other rheumatic diseases or healthy controls (P < 0.0001). Several of the missense mutations were located in the 3 immunoreceptor tyrosine activation motifs or the GTP binding domain, and this could lead to functional alterations in the TCR zeta chain. A splice variant of the TCR zeta chain with a codon CAG (glutamine) insertion between exons IV and V was found in half of the SLE and control samples. Two larger spliced isoforms of the TCR zeta chain, with an insertion of 145 bases and 93 bases between exons I and II, were found only in SLE T cells. We also identified various alternatively spliced forms of the TCR zeta chain resulting from the deletion of individual exons II, VI, or VII, or a combined deletion of exons V and VI; VI and VII; II, III, and IV; or V, VI, and VII in SLE T cells. The frequency of the deletion splice variants was significantly higher in SLE than in control samples (P = 0.004). These variations were observed in cDNA and may not reflect the status of the genomic DNA., Conclusion: These findings demonstrate that heterogeneous mutations/polymorphisms and alternative splicing of TCR zeta chain cDNA are more frequent in SLE T cells than in T cells from non-SLE subjects and may underlie the molecular basis of known T cell signaling abnormalities in this disease.