Do nanoparticles pose a threat to microbes? Response of soil microbial communities to Cu-nanoparticles

tekst w j. pol. i ang.Obecny stan wiedzy nie pozwala przewidzieć losu nanocząstek w środowisku, a w konsekwencji ich wpływu na organizmy nie będące celem ich działania. Celem doświadczenia była ocena wpływu zsyntetyzowanych nanocząstek miedzi związanych z matrycą krzemową (Cu/SiO2) na mikroorganizmy glebowe i ocena potencjalnego ryzyka środowiskowego. W ramach prac określono toksyczność nanocząstek miedzi względem mikroorganizmów referencyjnych wykorzystując metodę spot test. Przeprowadzono doświadczenie typu microcosm, w którym badano odpowiedź mikroflory glebowej na skażenie gleby nanocząstkami w stężeniu 10 mg·kg-1 (NP) i dawką 50-razy większą (50NP). Zmiany porównywano do układów skażonych jonami miedzi (10 mg Cu2+·kg-1) i 50Cu oraz odnosząc do nieskażonego układu kontrolnego (K). Pomiary prowadzono w dniu 1 i 28. Metoda Biolog oraz płytki Eco-Plates i FF zostały wykorzystane do określenia bioróżnorodności funkcjonalnej zespołu bakterii i grzybów. Całkowitą liczebność bakterii określono z wykorzystaniem metody reakcji PCR w czasie rzeczywistym (real-time quantitative PCR)

Multifunctional Bacteriochlorins from Selective Palladium-Coupling Reactions

Nonsymmetrical, multifunctional bacteriochlorin derivatives possessing different substituents at the β-pyrrolic positions have been prepared by stepwise, selective functionalization of 3,13-dibromo-5-methoxybacteriochlorin via palladium-coupling reactions. The new derivatives reported here include monovalent bioconjugatable bacteriochlorin, orthogonally protected bacteriochlorin amino acid, and push–pull bacteriochlorins. Taken together, this study provides a route to previously unavailable bacteriochlorin architectures for fundamental studies and diverse applications

Near-IR Emissive Chlorin–Bacteriochlorin Energy-Transfer Dyads with a Common Donor and Acceptors with Tunable Emission Wavelength

Design, synthesis, and optical properties of a series of novel chlorin–bacteriochlorin energy transfer dyads are described. Each dyad is composed of a common red-absorbing (645–646 nm) chlorin, as an energy donor, and a different near-IR emitting bacteriochlorin, as an energy acceptor. Each bacteriochlorin acceptor is equipped with a different set of auxochromes, so that each of them emits at a different wavelength. Dyads exhibit an efficient energy transfer (≥0.77) even for chlorin–bacteriochlorin pairs with large (up to 122 nm) separation between donor emission and acceptor absorption. Excitation of the chlorin donor results in relatively strong emission of the bacteriochlorin acceptor, with a quantum yield Φ_f range of 0.155–0.23 in toluene and 0.12–0.185 in DMF. The narrow, tunable emission band of bacteriochlorins enables the selection of a series of three dyads with well-resolved emissions at 732, 760, and 788 nm, and common excitation at 645 nm. Selected dyads have been also converted into bioconjugatable <i>N-</i>succinamide ester derivatives. The optical properties of the described dyads make them promising candidates for development of a family of near-IR fluorophores for simultaneous imaging of multiple targets, where the whole set of fluorophores can be excited with the common wavelength, and fluorescence from each can be independently detected

BODIPY–Bacteriochlorin Energy Transfer Arrays: Toward Near-IR Emitters with Broadly Tunable, Multiple Absorption Bands

A series of energy transfer arrays, comprising a near-IR absorbing and emitting bacteriochlorin, and BODIPY derivatives with different absorption bands in the visible region (503–668 nm) have been synthesized. Absorption band of BODIPY was tuned by installation of 0, 1, or 2 styryl substituents [2-(2,4,6-trimethoxyphenyl)­ethenyl], which leads to derivatives with absorption maxima at 503, 587, and 668 nm, respectively. Efficient energy transfer (>0.90) is observed for each dyad, which is manifested by nearly exclusive emission from bacteriochlorin moiety upon BODIPY excitation. Fluorescence quantum yield of each dyad in nonpolar solvent (toluene) is comparable with that observed for corresponding bacteriochlorin monomer, and is significantly reduced in solvent of high dielectric constants (DMF), most likely by photoinduced electron transfer. Given the availability of diverse BODIPY derivatives, with absorption between 500–700 nm, BODIPY–bacteriochlorin arrays should allow for construction of near-IR emitting agents with multiple and broadly tunable absorption bands. Solvent-dielectric constant dependence of Φ_f in dyads gives an opportunity to construct environmentally sensitive fluorophores and probes

Effect of Whole-Body Cryotherapy on Iron Status and Biomarkers of Neuroplasticity in Multiple Sclerosis Women

The aim of the study was to compare the effect of a series of 20 whole body cryotherapy (WBC) sessions on iron levels and neuroplasticity biomarkers in women with multiple sclerosis (MS) and healthy women. Consent was obtained from the Bioethics Committee at the Regional Medical Chamber in Krakow (87/KBL/OIL/2018; 8 May 2018). The study was registered in the Australian New Zealand Clinical Trials Registry (ACTRN12620001142921; 2 November 2020). The study included 30 people: 15 women with multiple sclerosis (mean age 41.53 &plusmn; 6.98 years) and 15 healthy women (mean age 38.47 &plusmn; 6.0 years). Both groups attended cryotherapy sessions. Venous blood was collected for analysis before the WBC session and after 20 sessions. In women with MS and healthy women, no significant effect of WBC on changes in the level biomarkers of neuroplasticity was found. There were also no statistically significant differences between the groups of the analyzed indices at the beginning of the study

The Effect of a New Derivative of Benzothiadiazole on the Reduction of Fusariosis and Increase in Growth and Development of Tulips

The use of inducers of systemic acquired resistance (SAR) is widely described in the literature. Such substances have important advantages over plant protection products (PPPs) and, thus, are often indicated as their alternatives. The main risk indicated in the context of the widespread use of SAR inducers is that of yield reduction that may result from the excessive metabolic imbalance of the treated plant. The general aim of the study presented was to check the effect of using a new active substance, namely N-methoxy-N-methylbenzo(1.2.3)thiadiazole-7-carboxamide (BTHWA), on tulips cultivated in greenhouse conditions. The plant response to BTHWA treatment was also analyzed in terms of the extent to which the growth–immunity phenomena would occur. Surprisingly, the application of BTHWA provided not only efficient protection against fusariosis but also resulted in the stimulation of the growth and development of tomato plants. The results proved very interesting as they stand in contrast to other results on SAR induction. The method of BTHWA application used in this study resulted in SAR induction at a level sufficient to provide effective protection and, at the same time, did not cause disruption to plant metabolism that would result in yield reduction