The larval Malpighian tubules of Chironomus tentans were studied using light and electron microscopy. The tubules are composed of two cell types: primary and stellate cells. Both cell types lack muscles, tracheoles, and laminate crystals in the cytoplasm and mitochondria in the microvilli. The primary cells exhibit long, wide basal membrane infoldings associated with mitochondria. They have a number of canaliculi and long, closely packed microvilli. The stellate cells possess shorter interconnecting basal infoldings and shorter, well-spaced microvilli. Both cell types are linked by septate and gap junctions. They have cytoplasmic processes and pedicels which enclose narrow slits between them and that are apposed to a basal lamella. In the 'fed' larva, the cells are stuffed with glycogen which is depleted in the 'starved' larva. Both cell types are involved in the vesicular transport of biliverdin. The presence of coated vesicles, tubular elements and various forms of lysosomes in the primary cells suggests they transport and break down functional hemoglobin. Structural modification of basal infoldings, canaliculi and microvilli is strongly correlated with increased secretory activity of the Malpighian tubules in 'fed' versus 'starved' larva.
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http://dx.doi.org/10.1016/0040-8166(88)90071-7 | DOI Listing |
ACS Appl Bio Mater
January 2025
Department of Chemistry, Indian Institute of Technology Palakkad, Palakkad, Kerala 678623, India.
The emerging prevalence of antimicrobial resistance demands cutting-edge therapeutic agents to treat bacterial infections. We present a synthetic strategy to construct sequence-defined oligomers (SDOs) by using dithiocarbamate (DTC). The antibacterial activity of the synthesized library of SDOs was studied using a Gram-positive and a Gram-negative .
View Article and Find Full Text PDFStroke
January 2025
Department of Neurology, Medical College of Georgia, Augusta University. (M.B.K., B.B., D.C.H.).
Background: Remote ischemic conditioning (RIC) is a simple and low-cost intervention that is thought to increase collateral blood flow through the vasodilatory effects of nitric oxide (NO) produced by the endothelium and red blood cells (RBCs). This study aims to investigate whether RIC affects RBC deformability and levels of NO and nitrite in patients with ischemic stroke.
Methods: This is a predefined substudy to the RESIST (Remote Ischemic Conditioning in Patients With Acute Stroke Trial) randomized clinical trial conducted in Denmark.
Arterioscler Thromb Vasc Biol
January 2025
Research Center of Clinical Medicine, Affiliated Hospital, Nantong University, China. (X.W., D.L.).
Background: Hyperglycemia is a major contributor to endothelial dysfunction and blood vessel damage, leading to severe diabetic microvascular complications. Despite the growing body of research on the underlying mechanisms of endothelial cell (EC) dysfunction, the available drugs based on current knowledge fall short of effectively alleviating these complications. Therefore, our endeavor to explore novel insights into the cellular and molecular mechanisms of endothelial dysfunction is crucial for the field.
View Article and Find Full Text PDFArterioscler Thromb Vasc Biol
January 2025
Department of Cardiovascular Medicine, The University of Tokyo, Bunkyo-ku, Japan. (H. Yagi, H.A., Q.L., A.S.-K., M.U., H.K., R.M., A.S., S.O., H.T., Norifumi Takeda, I.K.).
Background: Marfan syndrome (MFS) is an inherited disorder caused by mutations in the gene encoding fibrillin-1, a matrix component of extracellular microfibrils. The main cause of morbidity and mortality in MFS is thoracic aortic aneurysm and dissection, but the underlying mechanisms remain undetermined.
Methods: To elucidate the role of endothelial XOR (xanthine oxidoreductase)-derived reactive oxygen species in aortic aneurysm progression, we inhibited in vivo function of XOR either by endothelial cell (EC)-specific disruption of the gene or by systemic administration of an XOR inhibitor febuxostat in MFS mice harboring the missense mutation p.
Chem Sci
January 2025
State Key Laboratory of Silicate Materials for Architectures & State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & School of Chemistry, Chemical Engineering and Life Sciences & Laoshan Laboratory & School of Materials Science and Engineering, Wuhan University of Technology Wuhan 430070 China
Cell-interface engineering is a way to functionalize cells through direct or indirect self-assembly of functional materials around the cells, showing an enhancement to cell functions. Among the materials used in cell-interface engineering, natural biomolecules play pivotal roles in the study of biological interfaces, given that they have good advantages such as biocompatibility and rich functional groups. In this review, we summarize and overview the development of studies of natural biomolecules that have been used in cell-biointerface engineering and then review the five main types of biomolecules used in constructing biointerfaces, namely DNA polymers, amino acids, polyphenols, proteins and polysaccharides, to show their applications in green energy, biocatalysis, cell therapy and environmental protection and remediation.
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