Are there consistent effects of gut microbiota composition on performance, productivity and condition in poultry?

Microbiome of the gastrointestinal tract (GIT) has been identified as one of the crucial factors influencing the health and condition of domestic animals. The global poultry industry faces the challenge of understanding the complex relationship between gut microbiota composition and performance-related traits in birds. Considerable variation exists in the results of correlational studies using either 16S rRNA profiling or metagenomics to identify bacterial taxa associated with performance, productivity, or condition in poultry (e.g., body weight, growth rate, feeding efficiency, or egg yield). In this review, we survey the existing reports, discuss variation in research approaches, and identify bacterial taxa consistently linked to improved or deteriorated performance across individual poultry-focused studies. Our survey revealed high methodological heterogeneity, which was in contrast with vastly uniform focus of the research mainly on the domestic chicken (Gallus gallus) as a model. We also show that the bacterial taxa most frequently used in manipulative experiments and commercial probiotics intended for use in poultry (e.g., species of Lactobacillus, Bacillus, Enterococcus, or Bifidobacterium) do not overlap with the bacteria consistently correlated with their improved performance (Candidatus Arthromitus, Methanobrevibacter). Our conclusions urge for increased methodological standardization of the veterinary research in this field. We highlight the need to bridge the gap between correlational results and experimental applications in animal science. To better understand causality in the observed relationships, future research should involve a broader range of host species that includes both agricultural and wild models, as well as a broader range of age groups.

Fluorescence correlation spectroscopy in the study of the interaction between hyaluronan and positively charged surfactants.

The interaction between fluorescently labeled hyaluronan and cationic surfactants was studied using Fluorescence Correlation Spectroscopy. The hyaluronan was selected at two different molecular weights - specifically, 274 kDa and 710 kDa. Cetyltrimethylammonium bromide and Septonex® were chosen as cationic surfactants to interact with the negatively charged biopolymer. The study focused on changes in the diffusive behavior of a biopolymer that interacts with surfactant molecules in an aqueous environment. Various methods were applied to evaluate the obtained data, these including, among others, the Maximum Entropy Method, which provides the distributional dependences of diffusion coefficients. Without the surfactant, the studied biopolymers showed diffusion behavior comparable to that found in previously published studies. In the presence of surfactants, more intense interaction was observed between Cetyltrimethylammonium bromide and Septonex®. Comparing the molecular weights, the retention of intermolecular aggregates after the precipitation region for the lower weight and the disintegration of these aggregates for the higher weight were observed; moreover, they showed diffusion behavior comparable to the samples without the presence of the surfactant.

Nature of NMR Shifts in Paramagnetic Octahedral Ru(III) Complexes with Axial Pyridine-Based Ligands.

In recent decades, transition-metal coordination compounds have been extensively studied for their antitumor and antimetastatic activities. In this work, we synthesized a set of symmetric and asymmetric Ru(III) and Rh(III) coordination compounds of the general structure (Na+/K+/PPh4+/LH+) [trans-MIIIL(eq)nL(ax)2]- (M = RuIII or RhIII; L(eq) = Cl, n = 4; L(eq) = ox, n = 2; L(ax) = 4-R-pyridine, R = CH3, H, C6H5, COOH, CF3, CN; L(ax) = DMSO-S) and systematically investigated their structure, stability, and NMR properties. 1H and 13C NMR spectra measured at various temperatures were used to break down the total NMR shifts into the orbital (temperature-independent) and hyperfine (temperature-dependent) contributions. The hyperfine NMR shifts for paramagnetic Ru(III) compounds were analyzed in detail using relativistic density functional theory (DFT). The effects of (i) the 4-R substituent of pyridine, (ii) the axial trans ligand L(ax), and (iii) the equatorial ligands L(eq) on the distribution of spin density reflected in the "through-bond" (contact) and the "through-space" (pseudocontact) contributions to the hyperfine NMR shifts of the individual atoms of the pyridine ligands are rationalized. Further, we demonstrate the large effects of the solvent on the hyperfine NMR shifts and discuss our observations in the general context of the paramagnetic NMR spectroscopy of transition-metal complexes.

UV-responsive fluorescent behavior of pharmaceuticals assessed by UV-induced fingerprint spectroscopy (UV-IFS).

UV-induced fingerprint spectroscopy (UV-IFS), a new tool in a toolbox of analytical methods, is a powerful technique registering molecule-specific changes of fluorescence induced by UV irradiation. Analysis of fluorescence spectra of a sample prior and after UV irradiation enables an identification of a sample of a drug or pharmaceutics based on a comparison with signals of known standards. Moreover, UV-IFS uncovers the presence of undesired contaminations or intentional changes of the composition. Herein, we employ UV-IFS for qualitative as well as quantitative analysis of common medicines including analgesic/antipyretic (Acetaminophen), antihistamines (Loratadine and Desloratadine), and phosphodiesterase type 5 inhibitors (Tadalafil and Sildenafil citrate). UV irradiation (λem = 254 nm) for 2 - 10 min induced significant changes of fluorescence of the studied samples and according to the unique patterns, the quality and quantity were evaluated. Limits of detection for individual active ingredients were calculated as follows: Acetaminophen = 0.1 µg·mL-1, Loratadine = 0.1 µg·mL-1, Desloratadine = 0.01 µg·mL-1, Tadalafil = 0.04 µg·mL-1 and Sildenafil = 0.2 µg·mL-1. Moreover, genuine and fake CIALIS, VIAGRA and KAMAGRA tablets were reliably identified.

Use of Flavin-Related Cellular Autofluorescence to Monitor Processes in Microbial Biotechnology.

Cellular autofluorescence is usually considered to be a negative phenomenon because it can affect the sensitivity of fluorescence microscopic or flow cytometric assays by interfering with the signal of various fluorescent probes. Nevertheless, in our work, we adopted a different approach, and green autofluorescence induced by flavins was used as a tool to monitor fermentation employing the bacterium Cupriavidus necator. The autofluorescence was used to distinguish microbial cells from abiotic particles in flow cytometry assays, and it was also used for the determination of viability or metabolic characteristics of the microbial cells. The analyses using two complementary techniques, namely fluorescence microscopy and flow cytometry, are simple and do not require labor sample preparation. Flavins and their autofluorescence can also be used in a combination with other fluorophores when the need for multi-parametrical analyses arises, but it is wise to use dyes that do not emit a green light in order to not interfere with flavins' emission band (500-550 nm).

Menopause: neuroendocrine changes and hormone replacement therapy.

OBJECTIVE: We evaluated the effects of hormone replacement therapy (HRT) alone and in combination with a selective serotonin reuptake inhibitor on mood, cognition, and neuroendocrine parameters in peri- and postmenopausal women. METHODS: We measured neuroendocrine variations in peri- and postmenopausal depressed patients (DP) and postmenopausal normal control (NC) women (45 to 72 years old) before and after treatment with HRT alone and HRT combined with antidepressant medication. All subjects were without significant medical illness and off psychoactive or other medication that would interfere with neuroendocrine measures. RESULTS: Menopausal DP women reported greater severity of hot flashes, were less likely to be "morning" types, and had relatively good neuropsychological function compared with NC. DP and NC had comparable levels of reproductive hormones, with the exception of elevated prolactin levels, which increased, as did thyroid-stimulating hormone levels, in response to estradiol treatment. DP had poor sleep quality as measured both by subjective ratings and objective polysomnographic measures compared with NC. In DP estradiol did not enhance the effect of antidepressant alone on mood ratings. CONCLUSION: These findings may differ from other reports in the literature as a function of diagnoses of major depressive episode, randomized controlled trials, or dose and preparation of HRT. Further work is needed on the differential effect of treatment regimens in these disturbances that are evident primarily in baseline neuroendocrine function.