Digestive brush-border enzymes in particulate form have been reported in the intestinal lumen in vivo and in medium from organ explants in vitro. It has been suggested that these particles derive from membrane shedding of the apical brush border. This study describes the isolation and characterization of particles derived from the 105,000 x g supernatant fraction of intestinal luminal washings and from light scrapings of the mucosa itself after fat feeding of rats. These fractions were separated in a continuous NaBr gradient, producing a visible band of 1.07-1.08 g/liter density and resulting in a 15-fold enrichment of intestinal alkaline phosphatase in the band fraction. Other brush-border hydrolases were represented in the banded fraction, but at specific activities only 1/5th to 1/36th that of the brush border. The major phospholipid in the fraction was phosphatidylcholine (58 +/- 15%), containing 75% saturated fatty acids. In contrast, the major brush-border phospholipid was phosphatidyl-ethanolamine. These characteristics showed that the particles derived from the lumen and mucosal surface were not identical to fragments of the brush border. Electron microscopy of the banded fraction revealed partially coiled membrane fragments. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blots, some proteins (e.g. surfactant protein B, collagenous protein 4) were found in common between the intestinal particles and rat pulmonary surfactant. These data suggest the production of a particle secreted by rat intestine that differs from brush-border membranes and that shares some morphological and biochemical similarities with pulmonary surfactant.
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Int J Mol Sci
January 2025
Department of Cell Biology, IFOM ETS-The AIRC Institute of Molecular Oncology, Via Adamello, 16, 20139 Milan, Italy.
The regeneration of endothelial cells (ECs) lining arteries, veins, and large lymphatic vessels plays an important role in vascular pathology. To understand the mechanisms of atherogenesis, it is important to determine what happens during endothelial regeneration. A comparison of these processes in the above-mentioned vessels reveals both similarities and some significant differences.
View Article and Find Full Text PDFNeotrop Entomol
January 2025
Depto de Biologia Geral, Univ Federal de Viçosa, Viçosa, Minas Gerais, Brazil.
Caterpillars of the genus Spodoptera are the main pests in soybean and cotton crops and Spodoptera cosmioides causes more severe losses than other caterpillars in these agricultural crops. However, there are few recommended insecticides for controlling this pest. Lambda-cyhalothrin is a pyrethroid used to control a wide spectrum of arthropods including lepidopterans.
View Article and Find Full Text PDFJ Poult Sci
January 2025
Laboratory of Animal Functional Anatomy (LAFA), Faculty of Agriculture, Shinshu University, Kami-ina, Nagano 399-4598, Japan.
This study clarified the histological changes in the mucosal epithelium of the chicken intestine during the pre- and post-hatching stages. The duodenum, jejunum, ileum, and colorectum were collected from embryos at 15, 17, 18, 19, and 21 days of incubation and from chicks at 1 and 3 days after hatching. Paraffin sections prepared from tissue samples were stained with periodic acid-Schiff followed by alcian blue for histological analysis and to detect goblet cells.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Energy & Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran.
Prior studies examined Acidocin 4356's antibacterial and antivirulence effects against Pseudomonas aeruginosa, including cell membrane penetration abilities. Building on prior research, an in-vitro co-culture of human cells was established to evaluate the selectivity of Acidocin (ACD) by concurrently cultivating human cells and bacterial pathogens. This study evaluated the antibacterial effectiveness of ACD against Acinetobacter baumannii and Pseudomonas aeruginosa.
View Article and Find Full Text PDFTissue Eng Regen Med
January 2025
Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Sao Paulo, 13083-100, Brazil.
Background: The main challenge in new drug development is accurately predicting the human response in preclinical models.
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