Characteristics and activities of estrone sulfate (E1S) and dehydroepiandrosterone sulfate (DHAS) sulfatases were studied in epithelium and stroma of benign hyperplastic tissues from human prostates. Tissues were obtained by suprapubic prostatectomy, and epithelium and stroma were separated mechanically by standard techniques. The assay procedure comprised homogenization in Tris-buffer, incubation of the homogenate with [3H]E1S or [3H]DHAS, separation of free steroids from nonhydrolyzed steroid sulfates by extraction with ether, and their final quantification by LSC. The main results were: (1) The pH-optimum of the sulfatase was found at pH 7.0. (2) The highest specific sulfatase activity was found in the epithelium and was associated with its nuclear fraction. (3) Michaelis-Menten constants Km (microM) were 8.7 +/- 1.4 (7) and 4.3 +/- 0.8 (5), maximum velocity rates Vmax (nmol/h x mgDNA) were 47.4 +/- 8.8 (7) and 8.4 +/- 1.5 (5) for E1S and DHAS, respectively (means +/- SEM (n]. (4) The enzymatic cleavage of E1-sulfate was competitively inhibited by DHA-sulfate and vice versa with inhibition constants Ki (microM) of 4.0 +/- 0.5 (2) for E1S and 2.7 +/- 0.4 (2) for DHAS. On the basis of these findings, possible roles of steroid sulfate-sulfatases in forming precursors of active androgens and estrogens from the high amounts of E1S and DHAS in blood are discussed.
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Int J Surg Case Rep
January 2025
King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia. Electronic address:
Introduction: The eyelid is a common site for cutaneous tumors; however, tubular apocrine adenoma is a rare presentation. The clinical presentation is variable and surgical excision is effective with low risk for recurrence.
Presentation Of Case: We report a 40-year-old female with recurrent tubular apocrine adenoma of eyelid mimicking eyelid malignancy.
Acta Histochem
January 2025
Section of Anatomy and Histology, Imaging Platform, Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, Florence 50134, Italy. Electronic address:
Epidemic keratoconjunctivitis (EKC) is one of the most severe clinical manifestations of human adenovirus ocular surface infection, which may lead to the formation of subepithelial infiltrates (SEIs) in the anterior corneal stroma in 20-50 % of cases. SEIs may be asymptomatic or give rise to corneal aberrations and visual impairment for months or years after acute infection, despite treatments. Here, we describe the ultrastructural and immunophenotypic features of the anterior corneal stroma of a patient who underwent superficial anterior lamellar keratoplasty (SALK) surgery to remove corneal opacities related to clinically significant and steroid-unresponsive, long-lasting SEIs after adenoviral EKC.
View Article and Find Full Text PDFAdv Healthc Mater
January 2025
Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, 19104, USA.
Here a bioengineered platform is introduced to investigate adverse effects of environmental materials on the human cornea. Using primary cells, this system is capable of reproducing the differentiated corneal epithelium and its underlying stroma in the human eye, which can then be treated with externally applied solid, liquid, or gaseous substances in a controlled manner and under physiologically relevant conditions. The proof-of-principle of how this system can be used to simulate human ocular exposure to different classes of environmental toxicants for direct visualization and quantitative analysis of their potential to induce acute corneal injury and inflammation is demonstrated.
View Article and Find Full Text PDFJ Ocul Pharmacol Ther
January 2025
Ophtalmology Department, Rouen University Hospital, Rouen, France.
Cyclosporin A (CsA) is a drug used to prevent immune rejection in corneal transplantation. Most grafts performed today are endothelial grafts which are complicated with poor penetration of CsA into the endothelium due to its hydrophobicity. To improve CsA penetration into the corneal a new ocular formulation of CsA 2% with Miglyol was developed and is commercially available.
View Article and Find Full Text PDFAPMIS
January 2025
Department of Clinical Sciences, Malmö, Lund University, Malmö, Sweden.
The role of the vitamin D receptor (VDR) in inflammatory bowel disease (IBD) is poorly described. The aim of this study was to examine the relationship between immunohistochemical VDR expression and IBD activity. The immunohistochemical expression of VDR was analysed in biopsies from active and inactive IBD in 28 patients (ulcerative colitis: 21, Crohn's disease: 7) and 12 non-IBD controls.
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