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1.
Biochemistry (Mosc) ; 89(Suppl 1): S180-S204, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38621750

RESUMEN

In many proteins, supplementary metal-binding centers appear under stress conditions. They are known as aberrant or atypical sites. Physico-chemical properties of proteins are significantly changed after such metal binding, and very stable protein aggregates are formed, in which metals act as "cross-linking" agents. Supplementary metal-binding centers in proteins often arise as a result of posttranslational modifications caused by reactive oxygen and nitrogen species and reactive carbonyl compounds. New chemical groups formed as a result of these modifications can act as ligands for binding metal ions. Special attention is paid to the role of cysteine SH-groups in the formation of supplementary metal-binding centers, since these groups are the main target for the action of reactive species. Supplementary metal binding centers may also appear due to unmasking of amino acid residues when protein conformation changing. Appearance of such centers is usually considered as a pathological process. Such unilateral approach does not allow to obtain an integral view of the phenomenon, ignoring cases when formation of metal complexes with altered proteins is a way to adjust protein properties, activity, and stability under the changed redox conditions. The role of metals in protein aggregation is being studied actively, since it leads to formation of non-membranous organelles, liquid condensates, and solid conglomerates. Some proteins found in such aggregates are typical for various diseases, such as Alzheimer's and Huntington's diseases, amyotrophic lateral sclerosis, and some types of cancer.


Asunto(s)
Metales , Estrés Oxidativo , Metales/química , Metales/metabolismo , Oxidación-Reducción , Procesamiento Proteico-Postraduccional
2.
Vet Res Commun ; 48(1): 153-164, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37594698

RESUMEN

Although the herbicide glyphosate is widely used globally and considered safe, more evidence of its adverse effects on animals and humans is accumulating. The present investigation was aimed at evaluating the impact of different glyphosate concentrations on zootechnical characteristics and clinical, biochemical and immunological blood parameters in Ross 308 broiler chickens. Four groups were employed, including untreated control and three experimental groups fed diets enriched with glyphosate at doses of 10, 20 and 100 ppm that conformed to 0.5, 1 and 5 maximum residue limits, respectively. The results showed that glyphosate is a stress factor triggering a multifaceted effect on important blood parameters (e.g., white blood cell and phagocytic counts), which was shown for the first time in the experiments involving productive meat-type poultry. It was first revealed that glyphosate-induced changes in blood parameters may be related to a negative impact on the zootechnical characteristics including the digestive tract organ development and body weight gain. The study findings suggested that exposure to glyphosate in the feedstuffs can adversely affect the physiological condition and productivity of broilers.


Asunto(s)
Glifosato , Herbicidas , Humanos , Animales , Pollos/fisiología , Herbicidas/toxicidad , Exposición Dietética , Fenómenos Fisiológicos Nutricionales de los Animales , Dieta/veterinaria , Alimentación Animal/análisis , Suplementos Dietéticos
3.
J Org Chem ; 88(17): 12542-12564, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37593939

RESUMEN

Stereospecific α-glucosylation of primary and secondary OH-group at carbohydrate acceptors is achieved using glucosyl N-phenyl-trifluoroacetimidate (PTFAI) donor protected with an electron-withdrawing 2,4,5-trifluorobenzoyl (TFB) group at O-6 and the participating levulinoyl (Lev) group at O-3. New factors have been revealed that might explain α-stereoselectivity in the case of TFB and pentafluorobenzoyl (PFB) groups at O-6. They are of conformational nature and confirmed by DFT calculations. The potential of this donor, as well as the orthogonality of TFB and Lev protecting groups, is showcased by the synthesis of α-(1 → 3)-linked pentaglucoside corresponding to Aspergillus fumigatus α-(1 → 3)-d-glucan and of its hexasaccharide derivative, bearing ß-glucosamine residue at the non-reducing end.


Asunto(s)
Aspergillus fumigatus , Oligosacáridos , Teoría Funcional de la Densidad , Electrones , Glucanos
4.
Front Neuroanat ; 16: 940993, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36312299

RESUMEN

Despite a rapid growth in the application of modern techniques for visualization studies in life sciences, the classical methods of histological examination are yet to be outdated. Herein, we introduce a new approach that involves combining silver nitrate pretreatment and impregnation with consequent Nissl (cresyl violet) staining for cortex and striatum architectonics study on the same microscopy slide. The developed approach of hybrid staining provides a high-quality visualization of cellular and subcellular structures, including impregnated neurons (about 10%), Nissl-stained neurons (all the remaining ones), and astrocytes, as well as chromatophilic substances, nucleoli, and neuropil in paraffin sections. We provide a comparative study of the neuronal architectonics in both the motor cortex and striatum based on the differences in their tinctorial properties. In addition to a comparative study of the neuronal architectonics in both the motor cortex and striatum, the traditional methods to stain the cortex (motor and piriform) and the striatum are considered. The proposed staining approach compiles the routine conventional methods for thin sections, expanding avenues for more advanced examination of neurons, blood-brain barrier components, and fibers both under normal and pathological conditions. One of the main hallmarks of our method is the ability to detect changes in the number of glial cells. The results of astrocyte visualization in the motor cortex obtained by the developed technique agree well with the alternative studies by glial fibrillary acidic protein (GFAP) immunohistochemical reaction. The presented approach of combined staining has great potential in current histological practice, in particular for the evaluation of several neurological disorders in clinical, pre-clinical, or neurobiological animal studies.

5.
Antioxidants (Basel) ; 11(10)2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36290730

RESUMEN

Donors of nitroxyl and nitroxyl anion (HNO/NO-) are considered to be promising pharmacological treatments with a wide range of applications. Remarkable chemical properties allow nitroxyl to function as a classic antioxidant. We assume that HNO/NO- can level down the non-enzymatic glycation of biomolecules. Since erythrocyte hemoglobin (Hb) is highly susceptible to non-enzymatic glycation, we studied the effect of a nitroxyl donor, Angeli's salt, on Hb modification with methylglyoxal (MG) and organic peroxide-tert-butyl hydroperoxide (t-BOOH). Nitroxyl dose-dependently decreased the amount of protein carbonyls and advanced glycation end products (AGEs) that were formed in the case of Hb incubation with MG. Likewise, nitroxyl effectively protected Hb against oxidative modification with t-BOOH. It slowed down the destruction of heme, formation of carbonyl derivatives and inter-subunit cross-linking. The protective effect of nitroxyl on Hb in this system is primarily associated with nitrosylation of oxidized Hb and reduction of its ferryl form, which lowers the yield of free radical products. We suppose that the dual (antioxidant and antiglycation) effect of nitroxyl makes its application possible as part of an additional treatment strategy for oxidative and carbonyl stress-associated diseases.

6.
Pediatr Obes ; 17(11): e12958, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35770679

RESUMEN

OBJECTIVES: Determine whether the negative impact of the COVID-19 pandemic on weight gain trajectories among children attending well-child visits in New York City persisted after the public health restrictions were reduced. STUDY DESIGN: Multicenter retrospective chart review study of 7150 children aged 3-19 years seen for well-child care between 1 January 2018 and 4 December 2021 in the NYC Health and Hospitals system. Primary outcome was the difference in annual change of modified body mass index z-score (mBMIz) between the pre-pandemic and early- and late-pandemic periods. The mBMIz allows for tracking of a greater range of BMI values than the traditional BMI z-score. The secondary outcome was odds of overweight, obesity, or severe obesity. Multivariable analyses were conducted with each outcome as the dependent variable, and year, age category, sex, race/ethnicity, insurance status, NYC borough, and baseline weight category as independent variables. RESULTS: The difference in annual mBMIz change for pre-pandemic to early-pandemic = 0.18 (95% confidence interval [CI]: 0.15, 0.20) and for pre-pandemic to late-pandemic = 0.04 (95% CI: 0.01, 0.06). There was a statistically significant interaction between period and baseline weight category. Those with severe obesity at baseline had the greatest mBMIz increase during both pandemic periods and those with underweight at baseline had the lowest mBMIz increase during both pandemic periods. CONCLUSION: In NYC, the worsening mBMIz trajectories for children associated with COVID-19 restrictions did not reverse by 2021. Decisions about continuing restrictions, such as school closures, should carefully weigh the negative health impact of these policies.


Asunto(s)
COVID-19 , Obesidad Mórbida , Índice de Masa Corporal , COVID-19/epidemiología , Humanos , Ciudad de Nueva York/epidemiología , Sobrepeso/epidemiología , Pandemias/prevención & control , Estudios Retrospectivos
7.
Int J Mol Sci ; 22(24)2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34948445

RESUMEN

Dinitrosyl iron complexes (DNICs) are a physiological form of nitric oxide (•NO) in an organism. They are able not only to deposit and transport •NO, but are also to act as antioxidant and antiradical agents. However, the mechanics of hemoglobin-bound DNICs (Hb-DNICs) protecting Hb against peroxynitrite-caused, mediated oxidative modification have not yet been scrutinized. Through EPR spectroscopy we show that Hb-DNICs are destroyed under the peroxynitrite action in a dose-dependent manner. At the same time, DNICs inhibit the oxidation of tryptophan and tyrosine residues and formation of carbonyl derivatives. They also prevent the formation of covalent crosslinks between Hb subunits and degradation of a heme group. These effects can arise from the oxoferryl heme form being reduced, and they can be connected with the ability of DNICs to directly intercept peroxynitrite and free radicals, which emerge due to its homolysis. These data show that DNICs may ensure protection from myocardial ischemia.


Asunto(s)
Hierro/química , Metahemoglobina/metabolismo , Óxidos de Nitrógeno/química , Ácido Peroxinitroso/efectos adversos , Animales , Bovinos , Espectroscopía de Resonancia por Spin del Electrón , Humanos , Metahemoglobina/química , Oxidación-Reducción , Triptófano/química , Tirosina/química
8.
PeerJ ; 9: e12389, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34900412

RESUMEN

BACKGROUND: The key natural area of Russian reindeer (Rangifer tarandus, Nenets breed) is arctic zones, with severe climatic conditions and scarce feed resources, especially in the cold winter season. The adaptation of reindeer to these conditions is associated not only with the genetic potential of the animal itself. The rumen microbiome provides significant assistance in adapting animals to difficult conditions by participating in the fiber digestion. The aim of our study is to investigate the taxonomy and predicted metabolic pathways of the ruminal microbiota (RM) during the winter-spring (WS) and summer-autumn (SA) seasons, in calves and adult reindeer inhabiting the natural pastures of the Yamalo-Nenetsky Autonomous District of the Russian Federation. METHODS: The RM in reindeer was studied using the Next Generation Sequencing method with the MiSeq (Illumina, San Diego, CA, USA) platform. Reconstruction and prediction of functional profiles of the metagenome, gene families, and enzymes were performed using the software package PICRUSt2 (v.2.3.0). RESULTS: The nutritional value of WS and SA diets significantly differed. Crude fiber content in the WS diet was higher by 22.4% (p < 0.05), compared to SA, indicating possibly poorer digestibility and necessity of the adaptation of the RM to this seasonal change. A total of 22 bacterial superphyla and phyla were found in the rumen, superphylum Bacteroidota and phylum Firmicutes being the dominating taxa (up to 48.1% ± 4.30% and 46.1% ± 4.80%, respectively); while only two archaeal phyla presented as minor communities (no more then 0.54% ± 0.14% totally). The percentages of the dominating taxa were not affected by age or season. However, significant changes in certain minor communities were found, with seasonal changes being more significant than age-related ones. The percentage of phylum Actinobacteriota significantly increased (19.3-fold) in SA, compared to WS (p = 0.02) in adults, and the percentage of phylum Cyanobacteria increased up to seven-fold (p = 0.002) in adults and calves. Seasonal changes in RM can improve the ability of reindeer to withstand the seasons characterized by a low availability of nutrients. The PICRUSt2 results revealed 257 predicted metabolic pathways in RM: 41 pathways were significantly (p < 0.05) influenced by season and/or age, including the processes of synthesis of vitamins, volatile fatty acids, and pigments; metabolism of protein, lipids, and energy; pathogenesis, methanogenesis, butanediol to pyruvate biosynthesis, cell wall biosynthesis, degradation of neurotransmitters, lactic acid fermentation, and biosynthesis of nucleic acids. A large part of these changeable pathways (13 of 41) was related to the synthesis of vitamin K homologues. CONCLUSION: The results obtained improve our knowledge on the structure and possible metabolic pathways of the RM in reindeer, in relation to seasonal changes.

9.
Animals (Basel) ; 11(3)2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33810167

RESUMEN

The reindeer (Rangifer tarandus L.) is a unique animal inhabitant of arctic regions. Low ambient temperatures and scant diets (primarily, lichens) have resulted in different evolutional adaptations, including the composition of the ruminal microbiota. In the study presented here, the effects of seasonal and regional aspects of the composition of the ruminal microbiota in reindeer (Nenets breed, 38 animals) were studied (wooded tundra from the Yamalo-Nenetski Autonomous District (YNAD) vs. from the Nenetski Autonomous District (NAD)). The ruminal content of calves (n = 12) and adult animals (n = 26, 15 males and 11 females) was sampled in the summer (n = 16) and winter seasons (n = 22). The composition of the ruminal microbial population was determined by the V3-V4 16S rRNA gene region sequencing. It was found that the population was dominated by Bacteroidetes and Firmicutes phyla, followed by Spirochaetes and Verrucomicrobia. An analysis of the community using non-metric multidimensional scaling and Bray-Curtis similarity metrics provided evidence that the most influential factors affecting the composition of ruminal microbiota are the region (p = 0.001) and season (p = 0.001); heat map analysis revealed several communities that are strongly affected by these two factors. In the summer season, the following communities were significantly larger compared to in the winter season: Coriobactriaceae, Erysipelothrihaceae, and Mycoplasmataceae. The following communities were significantly larger in the winter season compared to in summer: Paraprevotellaceae, Butyrivibrio spp., Succiniclasticum spp., Coprococcus spp., Ruminococcus spp., and Pseudobutyrivibrio spp. In NAD (tundra), the following communities were significantly larger in comparison to YNAD (wooded tundra): Verrucomicrobia (Verruco-5), Anaerolinaceae, PeHg47 Planctomycetes, cellulolytic Lachnospiraceae, and Succiniclasticum spp. The following bacterial groups were significantly larger in YNAD in comparison to NAD: cellulolytic Ruminococaceae, Dehalobacteriaceae, Veillionelaceae, and Oscilospira spp. The significant differences in the ruminal microbial population were primarily related to the ingredients of diets, affected by region and season. The summer-related increases in the communities of certain pathogens (Mycoplasmataceae, Fusobacterium spp., Porphyromonas endodentalis) were found. Regional differences were primarily related to the ratio of the species involved in ruminal cellulose degradation and ruminal fatty acids metabolism; these differences reflect the regional dissimilarities in botanical diet ingredients.

10.
Animals (Basel) ; 11(2)2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33535430

RESUMEN

One of the main roles in poultry resistance to infections caused by Salmonella is attributed to host immunity and intestinal microbiota. We conducted an experiment that involved challenging Lohmann White laying hens with Salmonella Enteritidis (SE), feeding them a diet supplemented with an EOs-based phytobiotic Intebio®. At 1 and 7 days post-inoculation, the expression profiles of eight genes related to immunity, transport of nutrients in the intestine, and metabolism were examined. Cecal microbiome composition and blood biochemical/immunological indices were also explored and egg production traits recorded. As a result, the SE challenge of laying hens and Intebio® administration had either a suppressive or activating effect on the expression level of the studied genes (e.g., IL6 and BPIFB3), the latter echoing mammalian/human tissue-specific expression. There were also effects of the pathogen challenge and phytobiotic intake on the cecal microbiome profiles and blood biochemical/immunological parameters, including those reflecting the activity of the birds' immune systems (e.g., serum bactericidal activity, ß-lysine content, and immunoglobulin levels). Significant differences between control and experimental subgroups in egg performance traits (i.e., egg weight/number/mass) were also found. The phytobiotic administration suggested a positive effect on the welfare and productivity of poultry.

11.
Antioxidants (Basel) ; 10(2)2021 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-33562243

RESUMEN

The paper overviews the peculiarities of carbonyl stress in nucleus-free mammal red blood cells (RBCs). Some functional features of RBCs make them exceptionally susceptible to reactive carbonyl compounds (RCC) from both blood plasma and the intracellular environment. In the first case, these compounds arise from the increased concentrations of glucose or ketone bodies in blood plasma, and in the second-from a misbalance in the glycolysis regulation. RBCs are normally exposed to RCC-methylglyoxal (MG), triglycerides-in blood plasma of diabetes patients. MG modifies lipoproteins and membrane proteins of RBCs and endothelial cells both on its own and with reactive oxygen species (ROS). Together, these phenomena may lead to arterial hypertension, atherosclerosis, hemolytic anemia, vascular occlusion, local ischemia, and hypercoagulation phenotype formation. ROS, reactive nitrogen species (RNS), and RCC might also damage hemoglobin (Hb), the most common protein in the RBC cytoplasm. It was Hb with which non-enzymatic glycation was first shown in living systems under physiological conditions. Glycated HbA1c is used as a very reliable and useful diagnostic marker. Studying the impacts of MG, ROS, and RNS on the physiological state of RBCs and Hb is of undisputed importance for basic and applied science.

12.
Beilstein J Nanotechnol ; 12: 1392-1403, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35004123

RESUMEN

Impedance matching and heat management are important factors influencing the performance of terahertz sources. In this work we analyze thermal and radiative properties of such devices based on mesa structures of a layered high-temperature superconductor Bi2Sr2CaCu2O8+δ. Two types of devices are considered containing either a conventional large single crystal or a whisker. We perform numerical simulations for various geometrical configurations and parameters and make a comparison with experimental data for the two types of devices. It is demonstrated that the structure and the geometry of both the superconductor and the electrodes play important roles. In crystal-based devices an overlap between the crystal and the electrode leads to appearance of a large parasitic capacitance, which shunts terahertz emission and prevents impedance matching with open space. The overlap is avoided in whisker-based devices. Furthermore, the whisker and the electrodes form a turnstile (crossed-dipole) antenna facilitating good impedance matching. This leads to more than an order of magnitude enhancement of the radiation power efficiency in whisker-based, compared to crystal-based, devices. These results are in good agreement with presented experimental data.

13.
Materials (Basel) ; 13(20)2020 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-33080816

RESUMEN

X-ray absorption near edge structure (XANES) spectra for protein layers adsorbed at liquid interfaces in a Langmuir trough have been recorded for the first time. We studied the parkin protein (so-called E3 ubiquitin ligase), which plays an important role in pathogenesis of Parkinson disease. Parkin contains eight Zn binding sites, consisting of cysteine and histidine residues in a tetracoordinated geometry. Zn K-edge XANES spectra were collected in the following two series: under mild radiation condition of measurements (short exposition time) and with high X-ray radiation load. XANES fingerprint analysis was applied to obtain information on ligand environments around zinc ions. Two types of zinc coordination geometry were identified depending on X-ray radiation load. We found that, under mild conditions, local zinc environment in our parkin preparations was very similar to that identified in hemoglobin, treated with a solution of ZnCl2 salt. Under high X-ray radiation load, considerable changes in the zinc site structure were observed; local zinc environment appeared to be almost identical to that defined in Zn-containing enzyme alkaline phosphatase. The formation of a similar metal site in unrelated protein molecules, observed in our experiments, highlights the significance of metal binding templates as essential structural modules in protein macromolecules.

14.
Front Microbiol ; 11: 1626, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32849336

RESUMEN

Two novel antimicrobial surface coatings were assessed for their lasting antibacterial effect under simulated space conditions during the SIRIUS-19 study. Because long-term space travel can affect the human immune system, astronauts are particularly susceptible to infectious disease. Moreover, the space flight environment can alter the composition of microbial communities within the spacecraft and increase bacterial virulence and resistance to antibiotics. In addition to protecting the crew from infection by human pathogens, prevention and elimination of bacterial contamination is important to avoid corrosion and damage of the technical equipment. The antimicrobial coating AGXX® consists of micro-galvanic cells composed of silver and ruthenium which damage bacterial cells through the release of reactive oxygen species. Over the last years, several studies on the antimicrobial effect of AGXX® have demonstrated an effective inhibition of growth and even complete elimination of many pathogenic bacteria - including multiresistant microorganisms - as well as their biofilms. The second antimicrobial coating, GOX, consists of chemically modified graphene oxide. Through a positive surface charge and its flexible scaffold, GOX can multivalently bind and immobilize bacteria via electrostatic attraction. Here, AGXX® and GOX were applied to non-metallic carriers not previously tested. The antimicrobial coated materials, as well as uncoated control samples, were exposed in the SIRIUS artificial space module and analyzed at different time points during the 4-months isolation study. Survival and growth of airborne heterotrophic, aerobic bacteria on the surfaces were assessed by cultivation-based methods, employing growth conditions suitable for potential human pathogens. Human-associated, biofilm-forming Staphylococcus spp. (S. hominis, S. haemolyticus, and S. epidermidis) strongly dominated at all time points, most were resistant against erythromycin, kanamycin, and ampicillin. AGXX® coatings completely inhibited growth of these opportunistic pathogens on all tested surface materials. Particularly, AGXX®-cellulose fleece achieved a clear reduction in bacterial load able to recover post contact. GOX-cellulose fleece effectively immobilized bacteria. Sequence analysis of 16S rRNA gene amplicons revealed that the isolated Staphylococcus spp. did not dominate the overall bacterial community, accounting for only 0.1-0.4% of all sequences. Instead, molecular data revealed Lactobacillus, Comamonas, Pseudomonas, Sporosarcina, and Bacillus as the dominant genera across all samples and time points.

16.
J Neuroimmunol ; 337: 577070, 2019 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-31683117

RESUMEN

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS) which carries a significant burden of morbidity and mortality. Herein we examine the effects of acute treatment with tuftsin-phosphorylcholine (TPC), a novel immune-modulating helminth derived compound, on a murine model of MS. Experimental autoimmune encephalomyelitis (EAE) mice received acute treatment with TPC showed an improved clinical score and significantly less signs of inflammation and demyelination in CNS tissue compared with vehicle treated EAE mice. Our findings suggest that TPC may provide a beneficial clinical effect in EAE and may therefore have a potential value for ameliorating clinical manifestations and delaying disease progression in MS.


Asunto(s)
Encefalomielitis Autoinmune Experimental/patología , Encefalomielitis Autoinmune Experimental/prevención & control , Mediadores de Inflamación/antagonistas & inhibidores , Fosforilcolina/análogos & derivados , Tuftsina/uso terapéutico , Animales , Combinación de Medicamentos , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Mediadores de Inflamación/inmunología , Ratones , Ratones Endogámicos C57BL , Fosforilcolina/uso terapéutico
17.
Animals (Basel) ; 9(9)2019 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-31462004

RESUMEN

This study was performed to investigate the differential expression of eight immunity genes and the bacterial profiles in the caecum of growing chickens challenged with Salmonella enterica serovar Enteritidis (SE) at 1 and 23 days post inoculation (dpi) in response to SE infection at 19 days of age and administration of the phytobiotic Intebio. Following infection, the genes CASP6 and IRF7 were upregulated by greater than twofold. Chicks fed Intebio showed at 1 dpi upregulation of AvBD10, IL6, IL8L2, CASP6 and IRF7. At 23 dpi, expression of AvBD11, IL6, IL8L2, CASP6 and IRF7 lowered in the experiment subgroups as compared with the control. Examination of the caecal contents at 1 dpi demonstrated a significant decrease in the microbial biodiversity in the infected subgroup fed normal diet. Bacterial content of Lactobacillus and Bacillus declined, while that of Enterobacteriaceae rose. In the infected subgroup fed Intebio, a pronounced change in composition of the microflora was not observed. In the early infection stages, the phytobiotic seemed to promote response to infection. Subsequently, an earlier suppression of the inflammatory reaction took place in chickens fed Intebio. Thus, use of Intebio as a drug with phytobiotic activity in chickens, including those infected with Salmonella, proved to be promising.

18.
Front Microbiol ; 10: 543, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30941112

RESUMEN

The International Space Station (ISS) is a closed habitat in a uniquely extreme and hostile environment. Due to these special conditions, the human microflora can undergo unusual changes and may represent health risks for the crew. To address this problem, we investigated the antimicrobial activity of AGXX®, a novel surface coating consisting of micro-galvanic elements of silver and ruthenium along with examining the activity of a conventional silver coating. The antimicrobial materials were exposed on the ISS for 6, 12, and 19 months each at a place frequently visited by the crew. Bacteria that survived on the antimicrobial coatings [AGXX® and silver (Ag)] or the uncoated stainless steel carrier (V2A, control material) were recovered, phylogenetically affiliated and characterized in terms of antibiotic resistance (phenotype and genotype), plasmid content, biofilm formation capacity and antibiotic resistance transferability. On all three materials, surviving bacteria were dominated by Gram-positive bacteria and among those by Staphylococcus, Bacillus and Enterococcus spp. The novel antimicrobial surface coating proved to be highly effective. The conventional Ag coating showed only little antimicrobial activity. Microbial diversity increased with increasing exposure time on all three materials. The number of recovered bacteria decreased significantly from V2A to V2A-Ag to AGXX®. After 6 months exposure on the ISS no bacteria were recovered from AGXX®, after 12 months nine and after 19 months three isolates were obtained. Most Gram-positive pathogenic isolates were multidrug resistant (resistant to more than three antibiotics). Sulfamethoxazole, erythromycin and ampicillin resistance were most prevalent. An Enterococcus faecalis strain recovered from V2A steel after 12 months exposure exhibited the highest number of resistances (n = 9). The most prevalent resistance genes were ermC (erythromycin resistance) and tetK (tetracycline resistance). Average transfer frequency of erythromycin, tetracycline and gentamicin resistance from selected ISS isolates was 10-5 transconjugants/recipient. Most importantly, no serious human pathogens such as methicillin resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococci (VRE) were found on any surface. Thus, the infection risk for the crew is low, especially when antimicrobial surfaces such as AGXX® are applied to surfaces prone to microbial contamination.

19.
Cochrane Database Syst Rev ; 9: CD010485, 2017 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-28937705

RESUMEN

BACKGROUND: Genital Chlamydia trachomatis (C.trachomatis) infection may lead to pregnancy complications such as miscarriage, preterm labour, low birthweight, preterm rupture of membranes, increased perinatal mortality, postpartum endometritis, chlamydial conjunctivitis and C.trachomatis pneumonia.This review supersedes a previous review on this topic. OBJECTIVES: To establish the most efficacious and best-tolerated therapy for treatment of genital chlamydial infection in preventing maternal infection and adverse neonatal outcomes. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (26 June 2017) and reference lists of retrieved studies. SELECTION CRITERIA: Randomised controlled trials (RCTs) as well as studies published in abstract form assessing interventions for treating genital C.trachomatis infection in pregnancy. Cluster-RCTs were also eligible for inclusion but none were identified. Quasi-randomised trials and trials using cross-over design are not eligible for inclusion in this review. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for inclusion, assessed trial quality and extracted the data using the agreed form. Data were checked for accuracy. Evidence was assessed using the GRADE approach. MAIN RESULTS: We included 15 trials (involving 1754 women) although our meta-analyses were based on fewer numbers of studies/women. All of the included studies were undertaken in North America from 1982 to 2001. Two studies were low risk of bias in all domains, all other studies had varying risk of bias. Four other studies were excluded and one study is ongoing.Eight comparisons were included in this review; three compared antibiotic (erythromycin, clindamycin, amoxicillin) versus placebo; five compared an antibiotic versus another antibiotic (erythromycin, clindamycin, amoxicillin, azithromycin). No study reported different antibiotic regimens. Microbiological cure (primary outcome) Antibiotics versus placebo: Erythromycin (average risk ratio (RR) 2.64, 95% confidence interval (CI) 1.60 to 4.38; two trials, 495 women; I2 = 68%; moderate-certainty evidence), and clindamycin (RR 4.08, 95% CI 2.35 to 7.08; one trial, 85 women;low-certainty evidence) were associated with improved microbiological cure compared to a placebo control. In one very small trial comparing amoxicillin and placebo, the results were unclear, but the evidence was graded very low (RR 2.00, 95% CI 0.59 to 6.79; 15 women). One antibiotic versus another antibiotic: Amoxicillin made little or no difference in microbiological cure in comparison to erythromycin (RR 0.97, 95% CI 0.93 to 1.01; four trials, 466 women; high-certainty evidence), probably no difference compared to clindamycin (RR 0.96, 95% CI 0.89 to 1.04; one trial, 101 women; moderate-quality evidence), and evidence is very low certainty when compared to azithromycin so the effect is not certain (RR 0.89, 95% CI 0.71 to 1.12; two trials, 144 women; very low-certainty evidence). Azithromycin versus erythromycin (average RR 1.11, 95% CI 1.00 to 1.23; six trials, 374 women; I2 = 53%; moderate-certainty evidence) probably have similar efficacy though results appear to favour azithromycin. Clindamycin versus erythromycin (RR 1.06, 95% CI 0.97 to 1.15; two trials, 173 women; low-certainty evidence) may have similar numbers of women with a microbiological cure between groups.Evidence was downgraded for design limitations, inconsistency, and imprecision in effect estimates. Side effects of the treatment (maternal) (secondary outcome) Antibiotics versus placebo: side effects including nausea, vomiting, and abdominal pain, were reported in two studies (495 women) but there was no clear evidence whether erythromycin was associated with more side effects than placebo and a high level of heterogeneity (I2 = 78%) was observed (average RR 2.93, 95% CI 0.36 to 23.76). There was no clear difference in the number of women experiencing side effects when clindamycin was compared to placebo in one small study (5/41 versus 1/44) (RR 6.35, 95% CI 0.38 to 107.45, 62 women). The side effects reported were mostly gastrointestinal and also included resolving skin rashes. One antibiotic versus another antibiotic: There was no clear difference in incidence of side effects (including nausea, vomiting, diarrhoea and abdominal pain) when amoxicillin was compared to azithromycin based on data from one small study (36 women) (RR 0.56, 95% CI 0.24 to 1.31).However, amoxicillin was associated with fewer side effects compared to erythromycin with data from four trials (513 women) (RR 0.31, 95% CI 0.21 to 0.46; I2 = 27%). Side effects included nausea, vomiting, diarrhoea, abdominal cramping, rash, and allergic reaction.Both azithromycin (RR 0.24, 95% CI 0.17 to 0.34; six trials, 374 women) and clindamycin (RR 0.44, 95% CI 0.22 to 0.87; two trials, 183 women) were associated with a lower incidence of side effects compared to erythromycin. These side effects included nausea, vomiting, diarrhoea and abdominal cramping.One small study (101 women) reported there was no clear difference in the number of women with side effects when amoxicillin was compared with clindamycin (RR 0.57, 95% CI 0.14 to 2.26; 107 women). The side effects reported included rash and gastrointestinal complaints. Other secondary outcomes Single trials reported data on repeated infections, preterm birth, preterm rupture of membranes, perinatal mortality and low birthweight and found no clear differences between treatments.Many of this review's secondary outcomes were not reported in the included studies. AUTHORS' CONCLUSIONS: Treatment with antibacterial agents achieves microbiological cure from C.trachomatis infection during pregnancy. There was no apparent difference between assessed agents (amoxicillin, erythromycin, clindamycin, azithromycin) in terms of efficacy (microbiological cure and repeat infection) and pregnancy complications (preterm birth, preterm rupture of membranes, low birthweight). Azithromycin and clindamycin appear to result in fewer side effects than erythromycin.All of the studies in this review were conducted in North America, which may limit the generalisability of the results. In addition, study populations may differ in low-resource settings and these results are therefore only applicable to well-resourced settings. Furthermore, the trials in this review mainly took place in the nineties and early 2000's and antibiotic resistance may have changed since then.Further well-designed studies, with appropriate sample sizes and set in a variety of settings, are required to further evaluate interventions for treating C.trachomatis infection in pregnancy and determine which agents achieve the best microbiological cure with the least side effects. Such studies could report on the outcomes listed in this review.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones por Chlamydia/tratamiento farmacológico , Chlamydia trachomatis , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Infecciones del Sistema Genital/tratamiento farmacológico , Amoxicilina/uso terapéutico , Azitromicina/uso terapéutico , Clindamicina/uso terapéutico , Eritromicina/uso terapéutico , Femenino , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/microbiología , Ensayos Clínicos Controlados Aleatorios como Asunto
20.
Cochrane Database Syst Rev ; 1: CD009273, 2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-28106904

RESUMEN

BACKGROUND: Hypertensive disorders in pregnancy are significant contributors to maternal and perinatal morbidity and mortality. These disorders include well-controlled chronic hypertension, gestational hypertension (pregnancy-induced hypertension) and mild pre-eclampsia. The definitive treatment for these disorders is planned early delivery and the alternative is to manage the pregnancy expectantly if severe uncontrolled hypertension is not present, with close maternal and fetal monitoring. There are benefits and risks associated with both, so it is important to establish the safest option. OBJECTIVES: To assess the benefits and risks of a policy of planned early delivery versus a policy of expectant management in pregnant women with hypertensive disorders, at or near term (from 34 weeks onwards). SEARCH METHODS: We searched Cochrane Pregnancy and Childbirth Trials Register (12 January 2016) and reference lists of retrieved studies. SELECTION CRITERIA: Randomised trials of a policy of planned early delivery (by induction of labour or by caesarean section) compared with a policy of delayed delivery ("expectant management") for women with hypertensive disorders from 34 weeks' gestation. Cluster-randomised trials would have been eligible for inclusion in this review, but we found none.Studies using a quasi-randomised design are not eligible for inclusion in this review. Similarly, studies using a cross-over design are not eligible for inclusion, because they are not a suitable study design for investigating hypertensive disorders in pregnancy. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed eligibility and risks of bias. Two review authors independently extracted data. Data were checked for accuracy. MAIN RESULTS: We included five studies (involving 1819 women) in this review.There was a lower risk of composite maternal mortality and severe morbidity for women randomised to receive planned early delivery (risk ratio (RR) 0.69, 95% confidence interval (CI) 0.57 to 0.83, two studies, 1459 women (evidence graded high)). There were no clear differences between subgroups based on our subgroup analysis by gestational age, gestational week or condition. Planned early delivery was associated with lower risk of HELLP syndrome (RR 0.40, 95% CI 0.17 to 0.93, 1628 women; three studies) and severe renal impairment (RR 0.36, 95% CI 0.14 to 0.92, 100 women, one study).There was not enough information to draw any conclusions about the effects on composite infant mortality and severe morbidity. We observed a high level of heterogeneity between the two studies in this analysis (two studies, 1459 infants, I2 = 87%, Tau2 = 0.98), so we did not pool data in meta-analysis. There were no clear differences between subgroups based on our subgroup analysis by gestational age, gestational week or condition. Planned early delivery was associated with higher levels of respiratory distress syndrome (RR 2.24, 95% CI 1.20 to 4.18, three studies, 1511 infants), and NICU admission (RR 1.65, 95% CI 1.13 to 2.40, four studies, 1585 infants).There was no clear difference between groups for caesarean section (RR 0.91, 95% CI 0.78 to 1.07, 1728 women, four studies, evidence graded moderate), or in the duration of hospital stay for the mother after delivery of the baby (mean difference (MD) -0.16 days, 95% CI -0.46 to 0.15, two studies, 925 women, evidence graded moderate) or for the baby (MD -0.20 days, 95% CI -0.57 to 0.17, one study, 756 infants, evidence graded moderate).Two fairly large, well-designed trials with overall low risk of bias contributed the majority of the evidence. Other studies were at low or unclear risk of bias. No studies attempted to blind participants or clinicians to group allocation, potentially introducing bias as women and staff would have been aware of the intervention and this may have affected aspects of care and decision-making.The level of evidence was graded high (composite maternal mortality and morbidity), moderate (caesarean section, duration of hospital stay after delivery for mother, and duration of hospital stay after delivery for baby) or low (composite infant mortality and morbidity). Where the evidence was downgraded, it was mostly because the confidence intervals were wide, crossing both the line of no effect and appreciable benefit or harm. AUTHORS' CONCLUSIONS: For women suffering from hypertensive disorders of pregnancy after 34 weeks, planned early delivery is associated with less composite maternal morbidity and mortality. There is no clear difference in the composite outcome of infant mortality and severe morbidity; however, this is based on limited data (from two trials) assessing all hypertensive disorders as one group.Further studies are needed to look at the different types of hypertensive diseases and the optimal timing of delivery for these conditions. These studies should also include infant and maternal morbidity and mortality outcomes, caesarean section, duration of hospital stay after delivery for mother and duration of hospital stay after delivery for baby.An individual patient meta-analysis on the data currently available would provide further information on the outcomes of the different types of hypertensive disease encountered in pregnancy.


Asunto(s)
Cesárea , Hipertensión , Trabajo de Parto Inducido , Complicaciones Cardiovasculares del Embarazo , Espera Vigilante , Cesárea/estadística & datos numéricos , Parto Obstétrico , Femenino , Edad Gestacional , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Trabajo de Parto Inducido/estadística & datos numéricos , Tiempo de Internación , Mortalidad Materna , Preeclampsia , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto
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