39 research outputs found

    Improved Performance of Near infrared Excitation Raman Spectroscopy Using Reflective Thin-film Gold on Glass Substrates for Cytology Samples

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    Confocal near-infrared Raman spectroscopy has been shown to have applications in the area of clinical biology. A source wavelength in the near infrared is preferred over visible wavelengths for inspecting biological samples due to superior wave number resolution and reduced photo damage. However, these excitation sources have a number of drawbacks when compared to lasers in the visible wavelength region, including the requirement to use expensive highly pure crystal substrates such as Raman grade calcium fluoride as well as long acquisition times due to the lower Raman scattering efficiency. This paper investigates the use of a reflective substrate comprising a low cost 100 nm thin-film gold on glass substrate, as an alternative. Similar to recent work that used stainless steel substrates, it is demonstrated that the thin-film gold coated substrates, which are relatively inexpensive, produce cell spectra with 1.65 times the signal to noise ratio when compared with spectra obtained from calcium fluoride under identical conditions, with no apparent background signal in the fingerprint region. Two prostate cell lines are examined having been deposited on glass, calcium fluoride, and thin-film gold on glass substrates using the Thin Prep standard. Background spectra from, and cell adhesion on, these three substrates are compared. A comparison of the intensities and signal to noise ratios of the resulting spectra, and their viability for classification using principle components analysis is performed, which further demonstrates the benefit of reflective substrates

    Refractive change following pseudophakic vitrectomy: a retrospective review

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    Background To assess the occurrence and magnitude of refractive change in pseudophakic eyes undergoing 20 gauge pars plana vitrectomy without scleral buckling and to investigate possible aetiological factors. Methods Retrospective case note review of 87 pseudophakic eyes undergoing 20 gauge pars plana vitrectomy for a variety of vitreo-retinal conditions over a three-year period. Anterior chamber depth (ACD) was measured before and after vitrectomy surgery in 32 eyes. Forty-three pseudophakic fellow eyes were used as controls. Results Eighty-seven eyes (84 patients) were included in the study. Mean spherical equivalent refraction prior to vitrectomy was -0.20 dioptres, which changed to a mean of -0.65 dioptres postoperatively (standard deviation of refractive change 0.59, range-2.13 to 0.75 dioptres) (p < 0.001). Sixty-one of the 87(70%) eyes experienced a myopic shift and 45(52%) eyes had a myopic shift of -0.5 dioptres or more. Mean fellow eye refraction was -0.19 dioptres preoperatively and -0.17 dioptres postoperatively (p = 0.14)(n = 37) Mean ACD preoperatively was 3.29 mm and postoperatively 3.27 mm (p = 0.53) (n = 32) and there was no significant change in ACD with tamponade use. Regression analysis revealed no statistically significant association between changes in anterior chamber depth, as well as a wide variety of other pre-, intra and postoperative factors examined, and the refractive change observed. Conclusion Significant refractive changes occur in some pseudophakic patients undergoing 20 g pars plana vitrectomy. The mean change observed was a small myopic shift but the range was large. The aetiology of the refractive change is uncertain

    Analysis of genetic variability in Turner syndrome linked to long-term clinical features

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    Background: Women with Turner syndrome (TS) (45,X and related karyotypes) have an increased prevalence of conditions such as diabetes mellitus, obesity, hypothyroidism, autoimmunity, hypertension, and congenital cardiovascular anomalies (CCA). Whilst the risk of developing these co-morbidities may be partly related to haploinsufficiency of key genes on the X chromosome, other mechanisms may be involved. Improving our understanding of underlying processes is important to develop personalized approaches to management. // Objective: We investigated whether: 1) global genetic variability differs in women with TS, which might contribute to co-morbidities; 2) common variants in X genes - on the background of haploinsufficiency - are associated with phenotype (a “two-hit” hypothesis); 3) the previously reported association of autosomal TIMP3 variants with CCA can be replicated. // Methods: Whole exome sequencing was undertaken in leukocyte DNA from 134 adult women with TS and compared to 46,XX controls (n=23), 46,XX women with primary ovarian insufficiency (n=101), and 46,XY controls (n=11). 1) Variability in autosomal and X chromosome genes was analyzed for all individuals; 2) the relation between common X chromosome variants and the long-term phenotypes listed above was investigated in a subgroup of women with monosomy X; 3) TIMP3 variance was investigated in relation to CCA. // Results: Standard filtering identified 6,457,085 autosomal variants and 126,335 X chromosome variants for the entire cohort, whereas a somatic variant pipeline identified 16,223 autosomal and 477 X chromosome changes. 1) Overall exome variability of autosomal genes was similar in women with TS and control/comparison groups, whereas X chromosome variants were proportionate to the complement of X chromosome material; 2) when adjusted for multiple comparisons, no X chromosome gene/variants were strongly enriched in monosomy X women with key phenotypes compared to monosomy X women without these conditions, although several variants of interest emerged; 3) an association between TIMP3 22:32857305:C-T and CCA was found (CCA 13.6%; non-CCA 3.4%, p<0.02). // Conclusions: Women with TS do not have an excess of genetic variability in exome analysis. No obvious X-chromosome variants driving phenotype were found, but several possible genes/variants of interest emerged. A reported association between autosomal TIMP3 variance and congenital cardiac anomalies was replicated

    Improved performance of near infrared excitation Raman spectroscopy using reflective thin-film gold on glass substrates for cytology samples

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    Confocal near-infrared Raman spectroscopy has been shown to have applications in the area of clinical biology. A source wavelength in the near infrared is preferred over visible wavelengths for inspecting biological samples due to superior wavenumber resolution and reduced photodamage. However, these excitation sources have a number of drawbacks when compared to lasers in the visible wavelength region, including the requirement to use expensive highly pure crystal substrates such as Raman grade calcium fluoride as well as long acquisition times due to the lower Raman scattering efficiency. This paper investigates the use of a reflective substrate comprising a low cost 100 nm thin-film gold on glass substrate, as an alternative. Similar to recent work that used stainless steel substrates, it is demonstrated that the thin-film gold coated substrates, which are relatively inexpensive, produce cell spectra with 1.65 times the signal to noise ratio when compared with spectra obtained from calcium fluoride under identical conditions, with no apparent background signal in the fingerprint region. Two prostate cell lines are examined having been deposited on glass, calcium fluoride, and thin-film gold on glass substrates using the ThinPrep standard. Background spectra from, and cell adhesion on, these three substrates are compared. A comparison of the intensities and signal to noise ratios of the resulting spectra, and their viability for classification using principle components analysis is performed, which further demonstrates the benefit of reflective substrates

    An integrated single-cell analysis of human adrenal cortex development

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    The adrenal glands synthesize and release essential steroid hormones such as cortisol and aldosterone, but many aspects of human adrenal gland development are not well understood. Here, we combined single-cell and bulk RNA sequencing, spatial transcriptomics, IHC, and micro-focus computed tomography to investigate key aspects of adrenal development in the first 20 weeks of gestation. We demonstrate rapid adrenal growth and vascularization, with more cell division in the outer definitive zone (DZ). Steroidogenic pathways favored androgen synthesis in the central fetal zone, but DZ capacity to synthesize cortisol and aldosterone developed with time. Core transcriptional regulators were identified, with localized expression of HOPX (also known as Hop homeobox/homeobox-only protein) in the DZ. Potential ligand-receptor interactions between mesenchyme and adrenal cortex were seen (e.g., RSPO3/LGR4). Growth-promoting imprinted genes were enriched in the developing cortex (e.g., IGF2, PEG3). These findings reveal aspects of human adrenal development and have clinical implications for understanding primary adrenal insufficiency and related postnatal adrenal disorders, such as adrenal tumor development, steroid disorders, and neonatal stress

    Reflections on the Formation and Growth of the SURE Network: a National Disciplinary Network to Enhance Undergraduate Research in the Sciences

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    The Science Undergraduate Research Experience (SURE) Network is an academic network comprised of nine Higher Education Institutions (HEI) in Ireland that seeks to enhance the profile of, and practices in, undergraduate research in the Sciences within the Technological Higher Education Sector. This paper presents the reflections of the network\u27s leaders on the formation and growth of the network over the period from 2015, just prior to its establishment, to 2020 when the network hosted its seventh undergraduate research conference, published its second undergraduate journal issue, and initiated a coordinated community of practice in response to the Covid-19 crisis. The paper presents the motivations of the leaders for establishing and joining the SURE network, their interpretation of how involvement in the network enhances practice in their own HEI, their reflections on how their own personal development was enhanced, their interpretation of the factors that have contributed to the success of the network, and the direction in which they see the network going in the future. The collective reflections of the leaders of the SURE Network, as presented in this paper, provide importance guidance for those seeking to establish similar academic networks, both in the area of undergraduate research and elsewhere

    Proneoplastic effects of PGE2 mediated by EP4 receptor in colorectal cancer

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    <p>Abstract</p> <p>Background</p> <p>Prostaglandin E<sub>2 </sub>(PGE<sub>2</sub>) is the major product of Cyclooxygenase-2 (COX-2) in colorectal cancer (CRC). We aimed to assess PGE<sub>2 </sub>cell surface receptors (EP 1–4) to examine the mechanisms by which PGE<sub>2 </sub>regulates tumour progression.</p> <p>Methods</p> <p>Gene expression studies were performed by quantitative RT-PCR. Cell cycle was analysed by flow cytometry with cell proliferation quantified by BrdU incorporation measured by enzyme immunoassay. Immunohistochemistry was employed for expression studies on formalin fixed paraffin embedded tumour tissue.</p> <p>Results</p> <p>EP4 was the most abundant subtype of PGE<sub>2 </sub>receptor in HT-29 and HCA7 cells (which show COX-2 dependent PGE<sub>2 </sub>generation) and was consistently the most abundant transcript in human colorectal tumours (n = 8) by qRT-PCR (ANOVA, p = 0.01). G0/G1 cell cycle arrest was observed in HT-29 cells treated with SC-236 5 μM (selective COX-2 inhibitor) for 24 hours (p = 0.02), an effect abrogated by co-incubation with PGE<sub>2 </sub>(1 μM). G0/G1 arrest was also seen with a specific EP4 receptor antagonist (EP4A, L-161982) (p = 0.01). Treatment of HT-29 cells with either SC-236 or EP4A caused reduction in intracellular cAMP (ANOVA, p = 0.01). Early induction in p21<sup>WAF1/CIP1 </sup>expression (by qRT-PCR) was seen with EP4A treatment (mean fold increase 4.4, p = 0.04) while other genes remained unchanged. Similar induction in p21<sup>WAF1/CIP1 </sup>was also seen with PD153025 (1 μM), an EGFR tyrosine kinase inhibitor, suggesting EGFR transactivation by EP4 as a potential mechanism. Additive inhibition of HCA7 proliferation was observed with the combination of SC-236 and neutralising antibody to amphiregulin (AR), a soluble EGFR ligand. Concordance in COX-2 and AR localisation in human colorectal tumours was noted.</p> <p>Conclusion</p> <p>COX-2 regulates cell cycle transition via EP4 receptor and altered p21<sup>WAF1/CIP1 </sup>expression. EGFR pathways appear important. Specific targeting of the EP4 receptor or downstream targets may offer a safer alternative to COX-2 inhibition in the chemoprevention of CRC.</p

    Pathogenic variants in RNPC3 are associated with hypopituitarism and primary ovarian insufficiency

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    Purpose We aimed to investigate the molecular basis underlying a novel phenotype including hypopituitarism associated with primary ovarian insufficiency. Methods We used next-generation sequencing to identify variants in all pedigrees. Expression of Rnpc3/RNPC3 was analyzed by in situ hybridization on murine/human embryonic sections. CRISPR/Cas9 was used to generate mice carrying the p.Leu483Phe pathogenic variant in the conserved murine Rnpc3 RRM2 domain. Results We described 15 patients from 9 pedigrees with biallelic pathogenic variants in RNPC3, encoding a specific protein component of the minor spliceosome, which is associated with a hypopituitary phenotype, including severe growth hormone (GH) deficiency, hypoprolactinemia, variable thyrotropin (also known as thyroid-stimulating hormone) deficiency, and anterior pituitary hypoplasia. Primary ovarian insufficiency was diagnosed in 8 of 9 affected females, whereas males had normal gonadal function. In addition, 2 affected males displayed normal growth when off GH treatment despite severe biochemical GH deficiency. In both mouse and human embryos, Rnpc3/RNPC3 was expressed in the developing forebrain, including the hypothalamus and Rathke’s pouch. Female Rnpc3 mutant mice displayed a reduction in pituitary GH content but with no reproductive impairment in young mice. Male mice exhibited no obvious phenotype. Conclusion Our findings suggest novel insights into the role of RNPC3 in female-specific gonadal function and emphasize a critical role for the minor spliceosome in pituitary and ovarian development and function

    When RON MET TAM in Mesothelioma: All Druggable for One, and One Drug for All?

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    Malignant pleural mesothelioma (MPM) is an aggressive inflammatory cancer with a poor survival rate. Treatment options are limited at best and drug resistance is common. Thus, there is an urgent need to identify novel therapeutic targets in this disease in order to improve patient outcomes and survival times. MST1R (RON) is a trans-membrane receptor tyrosine kinase (RTK), which is part of the c-MET proto-oncogene family. The only ligand recognized to bind MST1R (RON) is Macrophage Stimulating 1 (MST1), also known as Macrophage Stimulating Protein (MSP) or Hepatocyte Growth Factor-Like Protein (HGFL). In this study, we demonstrate that the MST1-MST1R (RON) signaling axis is active in MPM. Targeting this pathway with a small molecule inhibitor, LCRF-0004, resulted in decreased proliferation with a concomitant increase in apoptosis. Cell cycle progression was also affected. Recombinant MST1 treatment was unable to overcome the effect of LCRF-0004 in terms of either proliferation or apoptosis. Subsequently, the effect of an additional small molecular inhibitor, BMS-777607 (which targets MST1R (RON), MET, Tyro3, and Axl) also resulted in a decreased proliferative capacity of MPM cells. In a cohort of MPM patient samples, high positivity for total MST1R by IHC was an independent predictor of favorable prognosis. Additionally, elevated expression levels of MST1 also correlated with better survival. This study also determined the efficacy of LCRF-0004 and BMS-777607 in xenograft MPM models. Both LCRF-0004 and BMS-777607 demonstrated significant anti-tumor efficacy in vitro, however BMS-777607 was far superior to LCRF-0004. The in vivo and in vitro data generated by this study indicates that a multi-TKI, targeting the MST1R/MET/TAM signaling pathways, may provide a more effective therapeutic strategy for the treatment of MPM as opposed to targeting MST1R alone
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