61 research outputs found

    Quantification of 3D microstructural parameters of trabecular bone is affected by the analysis software

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    Over the last decades, the use of high-resolution imaging systems to assess bone microstructural parameters has grown immensely. Yet, no standard defining the quantification of these parameters exists. It has been reported that different voxel size and/or segmentation techniques lead to different results. However, the effect of the evaluation software has not been investigated so far. Therefore, the aim of this study was to compare the bone microstructural parameters obtained with two commonly used commercial software packages, namely IPL (Scanco, Switzerland) and CTan (Bruker, Belgium). We hypothesized that even when starting from the same segmented scans, different software packages will report different results. Nineteen trapezia and nineteen distal radii were scanned at two resolutions (20 mu m voxel size with microCT and HR-pQCT 60 mu m). The scans were segmented using the scanners' default protocol. The segmented images were analyzed twice, once with IPL and once with CTan, to quantify bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), trabecular number (Tb.N) and specific bone surface (BS/BV). Only small differences between IPL and CTan were found for BV/TV. For Tb.Th, Tb.Sp and BS/BV high correlations (R-2 >= 0.99) were observed between the two software packages, but important relative offsets were observed. For microCT scans, the offsets were relative constant, e.g., around 15% for Tb.Th. However, for the HR-pQCT scans the mean relative offsets ranged over the different bone samples (e.g., for Tb.Th from 14.5% to 19.8%). For Tb.N, poor correlations (0.43 We conclude that trabecular bone microstructural parameters obtained with IPL and CTan cannot be directly compared except for BV/TV. For Tb.Th, Tb.Sp and BS/BV, correction factors can be determined, but these depend on both the image voxel size and specific anatomic location. The two software packages did not produce consistent data on Tb.N. The development of a universal standard seems desirable

    High-Resolution Cone-Beam Computed Tomography is a Fast and Promising Technique to Quantify Bone Microstructure and Mechanics of the Distal Radius

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    Obtaining high-resolution scans of bones and joints for clinical applications is challenging. HR-pQCT is considered the best technology to acquire high-resolution images of the peripheral skeleton in vivo, but a breakthrough for widespread clinical applications is still lacking. Recently, we showed on trapezia that CBCT is a promising alternative providing a larger FOV at a shorter scanning time. The goals of this study were to evaluate the accuracy of CBCT in quantifying trabecular bone microstructural and predicted mechanical parameters of the distal radius, the most often investigated skeletal site with HR-pQCT, and to compare it with HR-pQCT. Nineteen radii were scanned with four scanners: (1) HR-pQCT (XtremeCT, Scanco Medical AG, @ (voxel size) 82 mu m), (2) HR-pQCT (XtremeCT-II, Scanco, @60.7 mu m), (3) CBCT (NewTom 5G, Cefla, @75 mu m) reconstructed and segmented using in-house developed software and (4) microCT (VivaCT40, Scanco, @19 mu m-gold standard). The following parameters were evaluated: predicted stiffness, strength, bone volume fraction (BV/TV) and trabecular thickness (Tb.Th), separation (Tb.Sp) and number (Tb.N). The overall accuracy of CBCT with in-house optimized algorithms in quantifying bone microstructural parameters was comparable (R-2 = 0.79) to XtremeCT (R-2 = 0.76) and slightly worse than XtremeCT-II (R-2 = 0.86) which were both processed with the standard manufacturer's technique. CBCT had higher accuracy for BV/TV and Tb.Th but lower for Tb.Sp and Tb.N compared to XtremeCT. Regarding the mechanical parameters, all scanners had high accuracy (R-2 >= 0.96). While HR-pQCT is optimized for research, the fast scanning time and good accuracy renders CBCT a promising technique for high-resolution clinical scanning

    Triple-negative breast cancer with brain metastases: a comparison between basal-like and non-basal-like biological subtypes

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    The aim of this study was to divide the group of triple-negative breast cancer patients with brain metastases into basal-like and non-basal-like biological subtypes in order to compare clinical features and survival rates in those two groups. A comprehensive analysis of 111 consecutive triple-negative breast cancer patients with brain metastases treated in the years 2003–2009 was performed. In 75 patients, immunohistochemistry was used as a surrogate of microarray in order to evaluate the expression of three basal markers: cytokeratin 5/6 (CK 5/6), EGFR/HER1 and c-KIT. The basal-like (ER/PgR/HER2-negative, CK5/6positive and/or HER1-positive) and non-basal-like (ER/PgR/HER2-negative, CK5/6-negative, HER1-negative) subsets were selected. Clinical features and survivals were compared in both groups. In the group of 111 triple-negative breast cancer patients, median DFS, OS and survival from brain metastases were 20, 29 and 4 months, respectively. In 75 patients who were evaluable for basal markers, median DFS, OS and survival from brain metastases were 18, 26 and 3.2 months, respectively. In the basal-like subtype, the survival rates were 15, 26 and 3 months, respectively, and in the non-basal-like subtypes, they were 20, 30 and 2.8 months, respectively. No statistically significant differences in survivals were detected between the basal-like and non-basal-like biological subtypes. Factors influencing survival from brain metastases were: Karnofsky performance status (KPS), the status of extracranial disease and age. Biological markers differentiating triple-negative group into basal-like and non-basal-like subtype (CK 5/6, HER1, c-KIT) had no influence on survival. In patients with triple-negative breast cancer and brain metastases, well-known clinical, but not molecular, features correlated with survival

    Antitumor Activity of Noscapine in Combination with Doxorubicin in Triple Negative Breast Cancer

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    The aim of this study was to investigate the anticancer activity and mechanism of action of Noscapine alone and in combination with Doxorubicin against triple negative breast cancer (TNBC).TNBC cells were pretreated with Noscapine or Doxorubicin or combination and combination index values were calculated using isobolographic method. Apoptosis was assessed by TUNEL staining. Female athymic Nu/nu mice were xenografted with MDA-MB-231 cells and the efficacy of Noscapine, Doxorubicin and combination was determined. Protein expression, immunohistochemical staining were evaluated in harvested tumor tissues. values of 36.16±3.76 and 42.7±4.3 µM respectively. The CI values (<0.59) were suggestive of strong synergistic interaction between Noscapine and Doxorubicin and combination treatment showed significant increase in apoptotic cells. Noscapine showed dose dependent reduction in the tumor volumes at a dose of 150–550 mg/kg/day compared to controls. Noscapine (300 mg/kg), Doxorubicin (1.5 mg/kg) and combination treatment reduced tumor volume by 39.4±5.8, 34.2±5.7 and 82.9±4.5 percent respectively and showed decreased expression of NF-KB pathway proteins, VEGF, cell survival, and increased expression of apoptotic and growth inhibitory proteins compared to single-agent treatment and control groups.Noscapine potentiated the anticancer activity of Doxorubicin in a synergistic manner against TNBC tumors via inactivation of NF-KB and anti-angiogenic pathways while stimulating apoptosis. These findings suggest potential benefit for use of oral Noscapine and Doxorubicin combination therapy for treatment of more aggressive TNBC

    A mouse model for triple-negative breast cancer tumor-initiating cells (TNBC-TICs) exhibits similar aggressive phenotype to the human disease

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    <p>Abstract</p> <p>Background</p> <p>Triple-negative breast cancer (TNBC) exhibit characteristics quite distinct from other kinds of breast cancer, presenting as an aggressive disease--recurring and metastasizing more often than other kinds of breast cancer, without tumor-specific treatment options and accounts for 15% of all types of breast cancer with higher percentages in premenopausal African-American and Hispanic women. The reason for this aggressive phenotype is currently the focus of intensive research. However, progress is hampered by the lack of suitable TNBC cell model systems.</p> <p>Methods</p> <p>To understand the mechanistic basis for the aggressiveness of TNBC, we produced a stable TNBC cell line by sorting for 4T1 cells that do not express the estrogen receptor (ER), progesterone receptor (PgR) or the gene for human epidermal growth factor receptor 2 (HER2). As a control, we produced a stable triple-positive breast cancer (TPBC) cell line by transfecting 4T1 cells with rat HER2, ER and PgR genes and sorted for cells with high expression of ER and PgR by flow cytometry and high expression of the HER2 gene by Western blot analysis.</p> <p>Results</p> <p>We isolated tumor-initiating cells (TICs) by sorting for CD24<sup>+</sup>/CD44<sup>high</sup>/ALDH1<sup>+ </sup>cells from TNBC (TNBC-TICs) and TPBC (TPBC-TICs) stable cell lines. Limiting dilution transplantation experiments revealed that CD24<sup>+</sup>/CD44<sup>high</sup>/ALDH1<sup>+ </sup>cells derived from TNBC (TNBC-TICs) and TPBC (TPBC-TICs) were significantly more effective at repopulating the mammary glands of naïve female BALB/c mice than CD24<sup>-</sup>/CD44<sup>-</sup>/ALDH1<sup>- </sup>cells. Implantation of the TNBC-TICs resulted in significantly larger tumors, which metastasized to the lungs to a significantly greater extent than TNBC, TPBC-TICs, TPBC or parental 4T1 cells. We further demonstrated that the increased aggressiveness of TNBC-TICs correlates with the presence of high levels of mouse twenty-five kDa heat shock protein (Hsp25/mouse HspB1) and seventy-two kDa heat shock protein (Hsp72/HspA1A).</p> <p>Conclusions</p> <p>Taken together, we have developed a TNBC-TICs model system based on the 4T1 cells which is a very useful metastasis model with the advantage of being able to be transplanted into immune competent recipients. Our data demonstrates that the TNBC-TICs model system could be a useful tool for studies on the pathogenesis and therapeutic treatment for TNBC.</p

    XVIII.— Tristichia ovensi

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    Correlation Between Cone-Beam Computed Tomography and High-Resolution Peripheral Computed Tomography for Assessment of Wrist Bone Microstructure

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    High-resolution peripheral quantitative computed tomography (HR-pQCT) is considered as the best technique to measure bone microarchitecture in vivo. However, a breakthrough for medical applications is inhibited because of the restricted field of view (∼9 mm) and a relatively long acquisition time (∼3 minutes). The goal of this study was to compare the accuracy of cone-beam computed tomography (CBCT) and HR-pQCT and to determine the agreement between CBCT and HR-pQCT in quantifying bone structural parameters. Nineteen trapezia of arthritic patients were scanned four times ex vivo: 1) CBCT (NewTom 5G, Cefla, at 75 μm); 2) HR-pQCT (XTremeCT-I, Scanco, at 82 μm); 3) HR-pQCT (XTremeCT-II, Scanco, at 60.7 μm); and 4) microCT (SkyScan1172, Bruker, at 19.84 μm). XTremeCT-I and XtremeCT-II were reconstructed, segmented, and analyzed following the manufacturer's guidelines. CBCT was reconstructed with in-house developed software and analyzed twice: once with an adaptive segmentation technique combined with a direct analysis method (AT-DM) and once with a Laplace-Hamming filtering technique combined with an indirect analysis method (LH-IM). Parameters of interest included bone volume fraction (BV/TV) and trabecular thickness (Tb.Th), separation (Tb.Sp), and number (Tb.N). The analyses of the CBCT data showed that the AT-DM analysis correlated better with microCT for BV/TV, Tb.Sp, and Tb.N, whereas the LH-IM technique correlated better for Tb.Th. Evaluated over all parameters, the coefficient of determination for XtremeCT-I, XtremeCT-II, and CBCT were higher as R2  = 0.68, 0.72, and 0.67, respectively. For CBCT, the correlations improved when three samples with very thin trabeculae close to each other were excluded and became similar to those for XtremeCT-I and XtremeCT-II. Interesting for clinical practice is that those bones could be identified automatically with the CBCT scanner. We conclude that CBCT produced similar accuracy as HR-pQCT in bone morphometric analyses of trapezia. The broader range of application, larger field of view, and shorter acquisition time make CBCT a valuable alternative to HR-pQCT. © 2019 American Society for Bone and Mineral Research.status: publishe
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