578 research outputs found
Quantification of Spatial Parameters in 3D Cellular Constructs Using Graph Theory
Multispectral three-dimensional (3D) imaging provides spatial information for biological structures that cannot be measured by traditional methods. This work presents a method of tracking 3D biological structures to quantify changes over time using graph theory. Cell-graphs were generated based on the pairwise distances, in 3D-Euclidean space, between nuclei during collagen I gel compaction. From these graphs quantitative features are extracted that measure both the global topography and the frequently occurring local structures of the âtissue constructs.â The feature trends can be controlled by manipulating compaction through cell density and are significant when compared to random graphs. This work presents a novel methodology to track a simple 3D biological event and quantitatively analyze the underlying structural change. Further application of this method will allow for the study of complex biological problems that require the quantification of temporal-spatial information in 3D and establish a new paradigm in understanding structure-function relationships
Pleural mesothelioma in a nine-month-old dog
This paper reports on an unusual case of pleural epitheloid mesothelioma in a nine-month-old male, mixed breed dog. The dog was presented in-extremis and, on post mortem examination, multiple, exophytic, frequently pedunculated, yellowish-red, soft to firm masses ranging from 3 mm to 6 cm in diameter were diffusely distributed over, and attached to, the pericardial and parietal pleural surfaces. Microscopically, these masses consisted of round to partially polygonalshaped, anaplastic cells with minimal cytoplasm and hyperchromatic nuclei covering papillomatous projections or as part of more densely cellular masses. A supporting fibrovascular stroma and mitotic figures were also evident. Constituent tumour cells were labeled positively with antibodies against both vimentin and cytokeratin. In contrast, the same cells exhibited equivocal labeling with an antibody directed against calretinin antigen and did not label with antibodies against carcinoembryonic antigen (CEA) and milk fat globule-related antigen (MFGRA). Such tumours are rare in dogs, particularly in such a young animal
Vitamin B12 status in patients of Turkish and Dutch descent with depression: A comparative cross-sectional study
Background: Studies have shown a clear relationship between depressive disorders and vitamin B12 deficiency. Gastroenteritis and Helicobacter pylori infections can cause vitamin B12 deficiency. Helicobacter pylori infections are not uncommon among people of Turkish descent in The Netherlands. Aim: To examine the frequency of vitamin B12 deficiency in depressive patients of Turkish descent and compare it to the frequency of vitamin B12 deficiency in depressive patients of Dutch descent. Methods: The present study is a comparative cross-sectional study of 47 patients of Turkish descent and 28 of Dutch descent. The depressive disorder diagnosis and differential diagnosis were made using the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, fourth edition text revision (SCID). The severity of the depressive symptoms was determined using the Beck Depression Inventory (BDI) and the 21-item Hamilton Depression Rating Scale (HAM-D-21). Serum baseline vitamin B6 and B12, folic acid and total serum homocysteine (tHcy) levels were measured. Results: The average ages of the patients of Turkish and Dutch descent were 40.57 and 44.75 years, respectively. There were no demonstrable differences between the serum vitamin B6, folic acid and tHcy levels in the two groups. The serum vitamin B12 levels were however clearly lower in the patients of Turkish descent than in those of Dutch descent. Vitamin B12 deficiency was however observed in 14 patients of Turkish descent and 1 of Dutch descent. This difference was significant. On the BDI, the patients of Turkish descent scored significantly higher than those of Dutch descent. Patients with vitamin B12 deficiency and those with hyperhomocysteinaemia had a significantly higher BDI score than patients with normal vitamin B12 and homocysteine levels. No relationship was observed with vitamin B12 and tHcy. Conclusion: Vitamin B12 deficiency occurs more frequently in depressive patients of Turkish than of Dutch descent. This is why it is advisable to test the vitamin B12 serum level in depressive patients of Turkish descent
Using Y-chromosome capture enrichment to resolve haplogroup H2 shows new evidence for a two-Path Neolithic expansion to Western Europe
Uniparentally-inherited markers on mitochondrial DNA (mtDNA) and the non-recombining regions of the Y chromosome (NRY), have been used for the past 30 years to investigate the history of humans from a maternal and paternal perspective.Researchers have preferred mtDNA due to its abundance in the cells, and comparatively high substitution rate. Conversely, the NRY is less susceptible to back mutations and saturation, and is potentially more informative than mtDNA owing to its longer sequence length. However, due to comparatively poor NRY coverage via shotgun sequencing, and the relatively low and biased representation of Y-chromosome variants on capture arrays such as the 1240K, ancient DNA studies often fail to utilize the unique perspective that the NRY can yield.Here we introduce a new DNA enrichment assay, coined YMCA (Y-mappable capture assay), that targets the âmappableâ regions of the NRY. We show that compared to low-coverage shotgun sequencing and 1240K capture, YMCA significantly improves the coverage and number of sites hit on the NRY, increasing the number of Y-haplogroup informative SNPs, and allowing for the identification of previously undiscovered variants.To illustrate the power of YMCA, we show that the analysis of ancient Y-chromosome lineages can help to resolve Y-chromosomal haplogroups. As a case study, we focus on H2, a haplogroup associated with a critical event in European human history: the Neolithic transition. By disentangling the evolutionary history of this haplogroup, we further elucidate the two separate paths by which early farmers expanded from Anatolia and the Near East to western Europe.Competing Interest StatementThe authors have declared no competing interest.Introduction Results and Discussion - Validating the performance of YMCA - Application of YMCA to YHG H2 as a case study - Identifying diagnostic SNPs for improved YHG H2 resolution Discussion Materials and Methods - Data - Contamination quality filtering - Method of Y Haplogroup Assignment - Comparing the Performance of our Y-capture Array Phylogenetic Tree Reconstructio
Coupled Analysis of In Vitro and Histology Tissue Samples to Quantify Structure-Function Relationship
The structure/function relationship is fundamental to our understanding of biological systems at all levels, and drives most, if not all, techniques for detecting, diagnosing, and treating disease. However, at the tissue level of biological complexity we encounter a gap in the structure/function relationship: having accumulated an extraordinary amount of detailed information about biological tissues at the cellular and subcellular level, we cannot assemble it in a way that explains the correspondingly complex biological functions these structures perform. To help close this information gap we define here several quantitative temperospatial features that link tissue structure to its corresponding biological function. Both histological images of human tissue samples and fluorescence images of three-dimensional cultures of human cells are used to compare the accuracy of in vitro culture models with their corresponding human tissues. To the best of our knowledge, there is no prior work on a quantitative comparison of histology and in vitro samples. Features are calculated from graph theoretical representations of tissue structures and the data are analyzed in the form of matrices and higher-order tensors using matrix and tensor factorization methods, with a goal of differentiating between cancerous and healthy states of brain, breast, and bone tissues. We also show that our techniques can differentiate between the structural organization of native tissues and their corresponding in vitro engineered cell culture models
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