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Association Between Zinc Levels and the Impact of Its Deficiency on Idiopathic Male Infertility: An Up-to-Date Review
No full textBackground: Zinc (Zn) is an essential metal that plays a critical role in normal testicular development, spermatogenesis, prevention of sperm degradation, and overall male fertility. This review aims to offer a comprehensive and current overview of seminal plasma Zn levels in fertile men worldwide. It also aims to compare Zn levels in seminal plasma and blood (serum/plasma) between infertile men (cases) and fertile men (controls), examine the impact of Zn on sperm quality and the reproductive hormone, and highlight the effects of Zn supplementation therapy in male infertility. Methods: To achieve these goals, peer-reviewed studies from 2000 to 2024 were interrogated with regard to strict inclusion/exclusion criteria and were then thoroughly reviewed and analyzed. Results: Our findings indicate that maintaining optimal seminal plasma Zn levels is crucial, as low Zn levels are linked to impaired spermatogenesis and male infertility, while high Zn levels can cause oxidative stress and other changes that contribute to infertility. Seminal plasma Zn levels from 100 to 200 mg/L among fertile men worldwide can be roughly considered safe. Comparative analysis showed that a greater number of studies reported lower levels of seminal Zn in cases than in controls. Research into the impact of Zn levels in seminal plasma has shown that, although the results are not yet conclusive, altered (non-normal) Zn levels could influence semen parameters—particularly motility, morphology, and sperm count—and the level of the reproductive hormone, testosterone. Zinc-deficient infertile men could benefit from supplement therapy. Conclusions: Assessment of seminal plasma Zn levels in infertile men could provide valuable information and aid in diagnosis and treatment planning
Stacking interactions of organometallic sandwich and half-sandwich compounds: crystallographic evidence and quantum chemical support
No full textThis review provides crystallographic insight into stacking interactions between aromatic ligands in organometallic sandwich and half-sandwich compounds obtained by analyzing all crystal structures deposited in the Cambridge Structural Database. The influence of various structural features of aromatic ligands onto their stacking interactions were considered, including ring size (cyclopentadienyl, benzene, tropylium, cyclooctatetraenide), substituents (toluene, p-cymene, methylcyclopentadienyl, pentamethylcyclopentadienyl) and fused rings (indenyl, naphthalene). The crystallographic data were supported by quantum chemical calculations of interaction energies, which show that coordination to transition metals can significantly strengthen stacking interactions of aromatic compounds. Particular attention was given to stacking interactions with large horizontal displacements, which are very important in molecular recognition process and enable formation of additional simultaneous interactions. Even though stacking interactions are shown to be the weakest type of interactions between metallocene compounds, they are shown to be very important supramolecular forces in crystal structures
Essential Oil Variability in the Genetically Depauperate Mediterranean Pine Pinus pinea L.
No full textABSTRACT The present paper deals with the variability in the composition of needle essential oil in the Mediterranean pine Pinus pinea L., a geographically widespread yet genetically depauperate species. The obtained results indicate that despite a lack of neutral genetic diversity, P. pinea exhibits significant variability in needle essential oil composition. In terms of the dominant terpene compounds, we distinguished essential oils with limonene dominance (20.4%?76.1%), an oil dominated by guaiol (12.7%) and limonene (11.4%) in approximately equal concentrations, and oils in which ?-pinene (24.0% and 42.4%) or α-pinene (13.8%?37.0%) were dominant (with limonene either completely absent or present in very small amounts). Principal component analysis (PCA) suggests the presence of five phytochemical groups of P. pinea, whereas agglomerative hierarchical cluster analysis (AHC) confirms the existence of four distinct groups. Given the differing outcomes between phenotypic traits and molecular markers, we strongly recommend integrating both approaches when designing genetic resource conservation programs for P. pinea
The Effect Grinding and Annealing Temperature on Microstructure and Magnetic Properties of The Pressed Powder Mixture of 20.0 wt% Fe and 80.0 wt% BaTiO3
No full textThe mixture of 20.0 wt% Fe and 80.0 wt% BaTiO3 powders was found to consist of a BaTiO3 matrix and composite particles comprising Fe cores and BaTiO3 shells. During the grinding of this mixture, several processes occur, such as pulverization of the particles of both powders; changes in the size, morphology and composition of aggregates, crushing of crystal grains, increase in the density of chaotically distributed dislocations; growth of internal microstrains; rise in the residual stress; decrease in the amount of crystalline and increase in the amount of amorphous phases, as well as oxidation of Fe into its oxides FeO, Fe3O4 and Fe2O3. These changes in chemical composition, morphology and microstructure substantially affect the magnetization of the pressed powder mixture. With increasing the grinding time from 0 to 90 min, the increase in magnetization is dominantly affected by crushing of Fe crystal grains. The decrease in magnetization during grinding from 90 to 120 min is caused by the decrease in the amount of metallic Fe by oxidation to FeO and increase in both the density of chaotically distributed dislocations and internal microstrains. Formation of Fe3O4 and Fe2O3 oxides has a prevailing effect on the increase in magnetization when grinding for longer than 130 min. Chemical and microstructural changes in the mixture of powders of 20.0 wt% Fe and 80.0 wt% BaTiO3 during heating affect the magnetization of cooled samples at 22°C. The powder is thermally stable up to 330°C. The magnetization of samples cooled to 22°C declines with increasing annealing temperature above 330°C. This decrease is caused by both the oxidation of Fe to FeO and formation of larger crystalline grains of Fe. The magnetization of samples heated up to 250°C remains unchanged. At higher temperatures, with increasing the temperature of the sample, its magnetization declines as a result of the transition of directed domains to a chaotic state caused by the effect of thermal energy, formation of larger crystal grains and oxidation of Fe into FeO
Imunoafinitetno izolovanje ekstracelularnih vezikula iz RWPE-1 i PC3 ćelijskih linija
No full textEkstracelularne vezikule (EV) su fosfolipidne nanočestice koje proizvode gotovo sve ćelije. One sadrže proteine, lipide i nukleinske kiseline i imaju ključnu ulogu u međućelijskoj komunikaciji, regulaciji imunskog odgovora i prenosu biomolekula između ćelija. Njihov sastav i funkcija odražavaju fiziološko i patološko stanje ćelije od koje potiču, što ih čini potencijalnim biomarkerima za različite bolesti, uključujući i tumore. Ipak, usled heterogenog sastava i veličine EV, i dalje postoji potreba za razvojem efikasnih metoda za njihovo izolovanje. U poslednje vreme, sve veću pažnju privlače nanoantitela (VHH fragmenti), koja su jedna od najmanjih funkcionalnih jedinica antitela. Nanoantitela su stabilna, specifična, i zbog svoje male veličine mogu vezivati teško dostupne konformacione epitope, što ih čini pogodnim alatima za izolovanje EV.
U ovom radu korišćena su tri različita nanoantitela imobilizovana na polimer radi selektivnog izolovanja EV iz medijuma zdrave epitelne ćelijske linije prostate, RWPE-1 i tumorske linije PC3. Fluorescentnom protočnom citometrijom uz upotrebu komercijalnih antitela na CD9, CD63 i CD81 proteine, ispitane su razlike u prisustvu površinskih markera EV poreklom iz ove dve ćelijske linije. Osim toga, tretmanom detergentom Tritonom X-100, potvrđeno je prisustvo lipidnih čestica, odnosno EV u dobijenim izolatima
Diazachrysene derivatives as autophagy inhibitors combating pancreatic ductal adenocarcinoma (PDAC) cells
No full textAutophagy is the intercellular process of degrading and recycling damaged organelles and proteins to maintain
homeostasis in eukaryotic cells.(1) Its dysfunction is related to many types of human carcinomas, therefore,
targeting autophagy emerged as a therapeutic strategy in cancer management. Depending on the tumor stage,
inducing and suppressing autophagy can alter tumor progression. Most clinical studies targeting autophagy in
cancer patients involve autophagy inhibition as a therapeutic approach in addition to standard therapy,
predominantly in advanced cancers.(2)
Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive form of pancreatic cancer considered to be
autophagy-dependent.(3) Due to the late-stage detection of PDAC, its challenging resectability and low response
to chemotherapy, there is a constant need to identify more effective therapeutics.
Lately, we reported on new antiviral 4,10-diazachrysene derivatives, identified as autophagy inhibitors, which
accumulate in the lysosomes, induce the expansion of vesicular compartments, and suppress
autophagosome-lysosome fusion in HeLa cells.(4,5,6)
Herein, both previously and newly synthesized 4,10-diazachrysene derivatives were investigated for their safety
profile and anticancer activity against MIA PaCa-2 and PANC-1 human pancreatic adenocarcinoma cell lines in
vitro and in vivo. For in vivo evaluation the zebrafish PDAC xenograft model was used. This study presents
autophagy inhibitors with prominent activity against PDAC cell lines as single agents. Additionally, potential
mechanisms of the anticancer activity of diazachrysenes will be discussed
Nanostructured Fluorapatite as a Multifunctional Material for Environmental Protection Solutions
No full textNanostructured fluorapatite (Ca₁₀(PO₄)₆F₂), traditionally known as a calcium phosphate-based bioceramic with tunable
morphology and surface chemistry, has attracted growing attention in recent years for its multifunctional role in
environmental protection. Owing to its high chemical stability, ion-exchange capabilities, and biocompatibility, fluorapatite
based nanomaterials are increasingly being explored as efficient agents for the removal of environmental pollutants.
Recent studies have demonstrated its efficacy in removing heavy metals ions (Pb2+, Cr3+, Fe3+), fluoride, and phosphate
through adsorption and ion substitution mechanisms [1-3]. Additionally, nano-FAP has been engineered with photoreactive
and luminescent dopants (e.g., Eu3+, Tb3+), enabling its application in the development of selective optical sensors for pH
and toxic metal ion detection [4]. Furthermore, the integration of nano-FAP into vanadate-based or agarose-supported
nanocomposites has shown promising results in photocatalytic degradation of organic pollutants under light sources [5]. The
antimicrobial properties of modified nano-FAP are also well documented [6,7]. These multifunctional properties—adsorptive
capacity, photocatalytic activity, luminescence, and biocompatibility—position nano-FAP as a versatile material for
sustainable green technologies.
However, futhere investigation into the long-term stability, environmental safety, and scalability of these nanostructures is
essential to advance their real-world applications. This work provides a comprehesive overview of current trends and outlines
key challenges in traslating laboratory-scale findings into practical environmental solutions
ATR–FTIR analysis of pruning residues from Aronia melanocarpa (black chokeberry)
No full textAronia (Aronia melanocarpa (Michx.) Britton is a valuable plant known for its numerous health benefits. Its berries possess exceptionally high phenolic content and antioxidant capacity compared to other fruits. While the berries have been extensively studied, limited data exist on pruning residues, which may also serve as a source of valuable compounds. Attenuated Total Reflection – Fourier transform infrared spectroscopy (ATR–FTIR) is a simple and rapid technique that provides information on the functional groups of compounds present in various samples, including wood [1]. Aronia wood has not been extensively studied using this technique. One study focused on the characterization of proanthocyanidins isolated from Aronia wood [2]. Therefore, further research on the characterization of aronia wood and bark is needed.
The aim of this study was to characterize and find the chemical differences between Aronia wood and bark using ATR–FTIR spectroscopy combined with principal component analysis (PCA). The bark and the wood were separated and pulverised. ATR–FTIR spectra were recorded and then analyzed using PCA. Several differences, mainly in peak intensities, were observed between the wood and bark spectra. Peaks contributing to the separation of bark from wood spectra were identified at 2850, 2920, 2360, 1290 and 1090 cm-1. The ATR–FTIR combined with PCA is a useful tool for the rapid characterization of different parts of aronia shoots
Pechini synthesis method of Ho2O3 nanoparticles and their harnessing for extremely sensitive electrochemical sensing of diuron in juice samples; theoretical insights into sensing principle
No full textThis study developed a new electrochemical sensor for diuron (DIU) detection using a carbon paste electrode (CPE) upgraded with Ho2O3 nanoparticles. The Pechini method was used to synthesize Ho2O3 nanoparticles. The nanostructure properties of the material were confirmed using X-ray powder diffraction (XRPD), attenuated total reflectance (ATR) - Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The material electrocatalytic features were investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). An analytical method for identifying and measuring DIU was established using square wave voltammetry (SWV). The proposed sensor exhibited a remarkable response to DIU, displaying a broad linear range (0.25 - 200 µM) and a detection limit of 0.03 µM. Its minimal influence from potential interfering substances confirmed the method's selectivity. When detecting DIU in water and juice samples, the CPE/Ho2O3 sensor showed good recovery results. The conventional UV–Vis detection method validated the sensor efficacy. © 202
Serum and Seminal Plasma Zinc Levels and Immunopositivity of the ZIP6 and ZIP14 Transporters in Men with Normo- and Teratozoospermia
No full textZinc plays a crucial role in spermatogenesis, sperm function, and fertilisation. Zinc homeostasis is regulated by ZIP and ZnT transporter proteins, which mediate Zn2+ influx and efflux across sperm cell membranes. This study analysed total Zn concentration in seminal plasma and serum of 10 normozoospermic and 32 teratozoospermic men involved in the process of infertility treatment, using inductively coupled plasma mass spectrometry. In addition, the expression of Zn transporters ZIP6 and ZIP14 in the sperm of two normozoospermic and two teratozoospermic men was analysed using immunofluorescence. Applying Student’s t test and the Mann–Whitney U test, we found no significant differences in Zn concentrations in seminal plasma and serum between groups. ZIP6 was mainly localised in the sperm head, with slightly higher immunopositivity in normozoospermic than teratozoospermic samples, but there was no statistically significant difference between the groups. ZIP14 was mainly found in the sperm head, and some teratozoospermic samples showed immunopositivity in the tail, although there were no significant differences in ZIP14 immunopositivity between normozoospermic and teratozoospermic samples. The results suggest that Zn concentrations in seminal plasma and serum, and the expression of ZIP6 and ZIP14, do not differ in normo- and teratozospermic samples, and emphasise the complex interplay of factors underlying male fertility