Protoporphyrin and zinc-protoporphyrin were measured in the erythrocytes of normal subjects, workers exposed to lead and patients with iron deficiency and erythropoietic protoporphyria (EPP). Results showed significantly higher levels of zinc-protoporphyrin in the lead-exposed workers (P < 0.0001), patients with iron deficiency (P < 0.0001) and EPP patients (P < 0.001) compared with normal subjects. The lead-exposed workers showed the highest levels of zinc-protoporphyrin, which were significantly greater than both the iron-deficient and EPP patients (P < 0.0001). They also showed a higher ratio of zinc-protoporphyrin to free protoporphyrin compared with normal subjects (P < 0.0001) but no significant difference in this ratio was found when compared with iron-deficient patients (P = 0.1). These results are discussed in light of the controversy concerning the mechanism of formation of zinc-protoporphyrin in lead exposure.
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http://dx.doi.org/10.1177/000456329803500313 | DOI Listing |
Langmuir
January 2025
Research Center for Water Resources and Interface Science, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China.
The mechanism of the emulsion polymerization of styrene to polystyrene nanoparticles (PSNPs) remains a subject of debate. Herein, a series of reaction parameters with different surfactant concentrations, monomer contents, temperatures, and equilibration times were investigated to understand the formation mechanism of PSNPs, which demonstrate a correlation between the properties of PSNPs and the mesostructure of the premix. Cooling the model systems with self-emulsifying nanodroplets (SENDs) in the early reaction stages resulted in the hollow polystyrene spheres (H-PSSs), ruptured PSNPs, and dandelion-like PSNPs, further indicating that the oil nanodroplets are the key sites for the formation of PSNPs.
View Article and Find Full Text PDFInt J Clin Health Psychol
October 2024
Key Laboratory of Cognition and Personality, Faculty of Psychology, Southwest University, Chongqing, China.
Ruminative reflection has been linked to enhanced executive control in processing internally represented emotional information, suggesting it may serve as an adaptive strategy for emotion regulation. Investigating the neural substrates of reflection can deepen our understanding of its adaptive properties. This study used network-based statistic (NBS)-Predict methodology to identify resting state functional connectivity (FC)-based predictors of ruminative reflection in a healthy sample.
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View Article and Find Full Text PDFCureus
December 2024
Pediatric Radiology, Detroit Medical Center, Wayne State University, Detroit, USA.
Pheochromocytoma is a catecholamine-secreting tumor that arises from the medullary chromaffin cells but can rarely be extra-adrenal in origin. We present a case of a 16-year-old female patient with uncontrolled hypertension, despite being on lisinopril and metoprolol, and associated left-sided chest pain, recurrent headaches, and an unintentional weight loss of 10 pounds in one month. Laboratory work-up showed a markedly elevated plasma metanephrine level of 4463.
View Article and Find Full Text PDFA two-month-old developmentally normal full-term female presented with severe feeding intolerance, progressive weight loss, and persistent fussiness, leading to multiple emergency department visits and eventual hospitalization. Initial evaluations, including laboratory tests and imaging, were unremarkable, prompting a series of diagnostic and therapeutic interventions. A multidisciplinary approach, including empiric gastroesophageal reflux disease (GERD) therapy, was started.
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