Tryptophan and its metabolites, 5-hydroxytryptophan, 5-hydroxytryptamine, 5-hydroxyindolacetic acid, as well as dopamine, homovanilic acid and 2,3-dihydroxyphenylacetic acid, were separated on phenyl bound silica gel using isocratic elution with phosphate buffer. The method was successfully transferred to several other phenyl HPLC columns from different manufacturers simply by adjusting the pH of the buffer. The method has been validated by the determination of the level of monoamines in rat hypothalamus.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/1099-0801(200005)14:3<205::AID-BMC976>3.0.CO;2-N | DOI Listing |
Probiotics Antimicrob Proteins
January 2025
State Key Laboratory of Pathogen and Biosecurity, Academy of Military Medical Sciences, No. 20 Dongda Street, Beijing, 100071, Fengtai District, China.
Human β-defensin (HBD) has been recognized as a promising antimicrobial agent due to its broad-spectrum antimicrobial activity against various pathogens. In our previous work, we engineered a chimeric human β-defensin, designated H4, by fusing human β-defensin 3 and human β-defensin 4, resulting in enhanced antimicrobial activity and salt stability. However, the high cost of chemical synthesis due to the relatively large number of amino acids in H4 has limited its applications.
View Article and Find Full Text PDFSci Rep
January 2025
Pharmaceutical Chemistry Department, Faculty of Pharmacy, Horus University, New Damietta, 34517, Egypt.
RP-HPLC technique was developed and optimized for simultaneous identification and estimation of nirmatrelvir (NIR) and ritonavir (RIT) in their new copackaged tablet. Stability of nirmatrelvir (NIR) was studied after exposure to different five stress conditions; alkali, acid, heat, photo and oxidation degradation. The chromatographic separation was achieved using VDSpher PUR 100 ODS (4.
View Article and Find Full Text PDFCell Death Dis
January 2025
In vitro Toxicology and Biomedicine, Dept. inaugurated by the Doerenkamp-Zbinden foundation, University of Konstanz, 78457, Konstanz, Germany.
Neurite degeneration (ND) precedes cell death in many neurodegenerative diseases. However, it remains unclear how this compartmentalized cell death process is orchestrated in the central nervous system (CNS). The establishment of a CNS axotomy model (using modified 3D LUHMES cultures) allowed us to study metabolic control of ND in human midbrain-derived neurons without the use of toxicants or other direct disturbance of cellular metabolism.
View Article and Find Full Text PDFCryobiology
January 2025
Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, United States of America. Electronic address:
Osmotic stresses during cryoprotectant loading induce changes in cellular volume, leading to membrane damage or even cell death. Appropriate model-guided mitigation of these osmotic gradients during cryoprotectant loading is currently lacking, but would be highly beneficial in reducing viability loss during the loading process. To address this need, we reformulate the two-parameter formalism described by Jacobs and Stewart for cryoprotectant loading under the constraint of constant cell volume.
View Article and Find Full Text PDFJ Chromatogr A
January 2025
Lab Essentials Applications Development, Sartorius Lab Instruments GmbH & Co. KG, Göttingen, Germany.
Adeno-associated viruses (AAV) are among the leading vectors for in vivo gene therapy. The purification of AAV remains a bottleneck as it typically requires multiple individual process steps, often resulting in product loss and high costs. Current downstream processes are usually serotype-specific and rely primarily on expensive affinity resins.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!