Collagen microarchitecture mechanically controls myofibroblast differentiation.

Altered microarchitecture of collagen type I is a hallmark of wound healing and cancer that is commonly attributed to myofibroblasts. However, it remains unknown which effect collagen microarchitecture has on myofibroblast differentiation. Here, we combined experimental and computational approaches to investigate the hypothesis that the microarchitecture of fibrillar collagen networks mechanically regulates myofibroblast differentiation of adipose stromal cells (ASCs) independent of bulk stiffness. Collagen gels with controlled fiber thickness and pore size were microfabricated by adjusting the gelation temperature while keeping their concentration constant. Rheological characterization and simulation data indicated that networks with thicker fibers and larger pores exhibited increased strain-stiffening relative to networks with thinner fibers and smaller pores. Accordingly, ASCs cultured in scaffolds with thicker fibers were more contractile, expressed myofibroblast markers, and deposited more extended fibronectin fibers. Consistent with elevated myofibroblast differentiation, ASCs in scaffolds with thicker fibers exhibited a more proangiogenic phenotype that promoted endothelial sprouting in a contractility-dependent manner. Our findings suggest that changes of collagen microarchitecture regulate myofibroblast differentiation and fibrosis independent of collagen quantity and bulk stiffness by locally modulating cellular mechanosignaling. These findings have implications for regenerative medicine and anticancer treatments

Mediastinal lymphoma in a young Turkish Angora cat

An 8-month old intact male Turkish Angora cat was referred to the Veterinary Medical Teaching Hospital (VMTH), Seoul National University, for an evaluation of anorexia and severe dyspnea. The thoracic radiographs revealed significant pleural effusion. A cytology evaluation of the pleural fluid strongly suggested a lymphoma containing variable sized lymphocytes with frequent mitotic figures and prominent nucleoli. The feline leukemia virus and feline immunodeficiency virus tests were negative. The cat was euthanized at his owner's request and a necropsy was performed. A mass was detected on the mediastinum and lung lobes. A histopathology evaluation confirmed the mass to be a lymphoma. Immunohistochemistry revealed the mass to be CD3 positive. In conclusion, the cat was diagnosed as a T-cell mediastinal lymphoma

Epidermal Cysts in a Tacrolimus Treated Renal Transplant Recipient

Tacrolimus, a calcineurin inhibitor, formerly also known as FK506, is a macrolactam drug isolated from Streptomyces tsukubaensis. Its mode of action closely parallels the action of cyclosprorin A (CsA) and can be used for the treatment of inflammatory and autoimmune skin diseases in which systemic CsA has proved effective against psoriasis, pyoderma gangrenosum, atopic dermatitis, lupus erythematosus and graft versus host disease (GVHD). Although several cases of epidermal cysts have been reported in patients using cyclosporine and other immunosuppressants after organ transplantation; such types of cases have yet not been reported after administration of tacrolimus. However, we report herein a case of presence of multiple, various sized epidermal cysts in a renal transplant recipient receiving tacrolimus

An accurate method for quantifying and analyzing copy number variation in porcine KIT by an oligonucleotide ligation assay

<p>Abstract</p> <p>Background</p> <p>Aside from single nucleotide polymorphisms, copy number variations (CNVs) are the most important factors in susceptibility to genetic disorders because they affect expression levels of genes. In previous studies, pyrosequencing, mini-sequencing, real-time PCR, invader assays and other techniques have been used to detect CNVs. However, the higher the copy number in a genome, the more difficult it is to resolve the copies, so a more accurate method for measuring CNVs and assigning genotype is needed.</p> <p>Results</p> <p>PCR followed by a quantitative oligonucleotide ligation assay (qOLA) was developed for quantifying CNVs. The accuracy and precision of the assay were evaluated for porcine <it>KIT</it>, which was selected as a model locus. Overall, the root mean squares of bias and standard deviation of qOLA were 2.09 and 0.45, respectively. These values are less than half of those in the published pyrosequencing assay for analyzing CNV in porcine <it>KIT</it>. Using a combined method of qOLA and another pyrosequencing for quantitative analysis of <it>KIT </it>copies with spliced forms, we confirmed the segregation of <it>KIT </it>alleles in 145 F₁animals with pedigree information and verified the correct assignment of genotypes. In a diagnostic test on 100 randomly sampled commercial pigs, there was perfect agreement between the genotypes obtained by grouping observations on a scatter plot and by clustering using the nearest centroid sorting method implemented in PROC FASTCLUS of the SAS package. In a test on 159 Large White pigs, there were only two discrepancies between genotypes assigned by the two clustering methods (98.7% agreement), confirming that the quantitative ligation assay established here makes genotyping possible through the accurate measurement of high <it>KIT </it>copy numbers (>4 per diploid genome). Moreover, the assay is sensitive enough for use on DNA from hair follicles, indicating that DNA from various sources could be used.</p> <p>Conclusion</p> <p>We have established a high resolution quantification method using an oligonucleotide ligation assay to measure CNVs, and verified the reliability of genotype assignment for random animal samples using the nearest centroid sorting method. This new method will make it more practical to determine <it>KIT </it>CNV and to genotype the complicated <it>Dominant White/KIT </it>locus in pigs. This procedure could have wide applications for studying gene or segment CNVs in other species.</p

Mesothelial Cyst of the Round Ligament Mimicking a Metastasis: a Case Report

A mesothelial cyst of the round ligament is a rare cause of an inguinal mass. Clinically, it is frequently misdiagnosed as one of commoner diseases such as an inguinal hernia, femoral hernia, lipoma, and lymphadenopathy upon physical examination. Some previous reports elaborated the sonographic features of a mesothelial cyst of the round ligament. However, to our knowledge, few reports have described the CT features of a mesothelial cyst. We illustrated here the sonographic and multidetector CT features of a case of a mesothelial cyst of the round ligament that presented as an inguinal palpable mass and mimicked a metastasis in a patient with a Sertoli-Leydig cell tumor of the ovary

Primary Large Cell Neuroendocrine Carcinoma of the Breast: Radiologic and Pathologic Findings

Some breast neoplasms are classified as primary neuroendocrine carcinomas because they are positive for neuroendocrine markers. Although neuroendocrine carcinomas can originate from various organs of the body, primary neuroendocrine carcinomas of the breast are extremely rare. The diagnosis of primary neuroendocrine carcinoma of the breast can only be made if nonmammary sites are confidently excluded or if an in situ component can be found. Here we report a primary large-cell neuroendocrine carcinoma (LCNL) involving the left breast. Breast ultrasonography revealed a lobulated, heterogeneous, low-echoic mass in the left breast, and the lesion ap-peared as a well-defined, highly-enhancing mass on a chest computed tomography scan. Ultrasound-guided core needle biopsy was performed on the mass, and primary LCNC was confirmed by histopathologic examination