The effects of subchronic (30 days) drinking water exposure of rats to ZnSO4 or Pb(CH3COO)2 alone or in combination on the adrenergically-mediated contractile responses of isolated vas deferens were studied. The contractile effects of the alpha 1, alpha 2-adrenoceptor agonist noradrenaline (NA) and to the alpha 1-adrenoceptor agonist 1-phenylephrine (1-PhE) were decreased after zinc exposure, whereas after lead exposure or lead plus zinc exposure they were not changed. The contractile responses to field electrical stimulation (FES, 0.1 Hz, 1 msec, 80 V) were diminished in amplitude in all metal-treated preparations as compared to controls. The yohimbine-induced restoration of the clonidine inhibited contractions in response to FES was decreased in both lead- and zinc-treated preparations, the EC50 for yohimbine being 0.018 +/- 0.001 microM in control preparations, 0.073 +/- 0.019 microM in lead-treated preparations and 0.056 +/- 0.021 microM in zinc-treated preparations. The calcium-channel blocker verapamil was found to inhibit at low concentrations and to increase at higher concentrations the FES-induced contractile responses in preparations from zinc-exposed rats. The inhibitory effect of cumulatively applied nitrendipine on the FES-induced contractions was increased in both lead- and zinc-treated smooth muscles, but was not altered in the preparations from lead plus zinc-treated rats. Therefore, subchronic exposure to subtoxic doses of lead of zinc led to different changes in the adrenergically-mediated contractility of isolated vas deferens. The changes induced by zinc exposure were not observed after lead plus zinc exposure. All these findings might be of pharmacological, toxicological or clinical importance.
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Background: Childhood obesity and the rate of its spread is a serious threat to the reproductive health of the nation, especially among boys, being a background for delaying sexual development and further disrupting fertility.
Aim: To study the peculiarities of the ratio of the level of leptin and a number of toxic and essential chemical trace elements in biological environments in adolescent boys aged 13-14 years with obesity and delayed sexual development.
Materials And Methods: Three groups of adolescents aged 13-14 years were studied and formed: the main ones - with constitutional exogenous obesity of 1-2 degrees (1-20 boys without secondary signs of puberty; 2 - 24 boys with 2-4 stages of puberty according to Tanner) and comparisons (3 - 15 boys with normal body weight and without deviations in puberty).
Small
January 2025
Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan.
Addressing the challenges of the efficiency and stability of red perovskite nanocrystals is imperative for the successful deployment of these materials in displays and lighting applications. the structural dynamic changes of red perovskite quantum dots (PQDs) are explored using a flow chemistry system to solve the above hurdles. First, the ultrabright red-emitting PQDs of CsPb(Br,I) are achieved by adjusting ligand distribution (oleic acid and oleyamine) in combination with different flow rates and equivalence ratios.
View Article and Find Full Text PDFEnviron Pollut
January 2025
Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, State Key Lab of Marine Environmental Science, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian 361102, China. Electronic address:
A major proportion of metal contaminants in aquatic environments is bound to suspended particulate matter (SPM), yet environmental monitoring typically focuses on dissolved metals, with the filtration step removing SPM. This step may inadvertently hide the potential risks posed by particulate metals. In this study, we used stable isotope tracers to quantify the contributions of SPM-bound metals to the bioaccumulation of nickel (Ni), copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb) in Ruditapes philippinarum, a widely distributed clam crucial to global aquaculture.
View Article and Find Full Text PDFJ Expo Sci Environ Epidemiol
January 2025
Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Background: Preterm birth (PTB) is a common pregnancy complication associated with significant neonatal morbidity. Prenatal exposure to environmental chemicals, including toxic and/or essential metal(loid)s, may contribute to PTB risk.
Objective: We aimed to summarize the epidemiologic evidence of the associations among levels of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), lead (Pb), and zinc (Zn) assessed during the prenatal period and PTB or gestational age at delivery; to assess the quality of the literature and strength of evidence for an effect for each metal; and to provide recommendations for future research.
Polymers (Basel)
January 2025
Department of Chemical Engineering, Dr B R Ambedkar National Institute of Technology, Jalandhar 144011, Punjab, India.
Antimicrobial polymeric coatings rely not only on their surface functionalities but also on nanoparticles (NPs). Antimicrobial coatings gain their properties from the addition of NPs into a polymeric matrix. NPs that have been used include metal-based NPs, metal oxide NPs, carbon-based nanomaterials, and organic NPs.
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