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Abstract

Until recently, little was known about the mechanism for killing and clearing bacteria from the bloodstream. Leukocyte phagocytosis could not be a mechanism for catching, killing and removing bacteria from the bloodstream because of many reasons. Recently accumulated data have led to the conclusion that in bacteremia, bacteria are quickly removed from the blood and erythrocytes are the main cells that capture, kill and remove bacteria. Data were also obtained that erythrocytes catch bacteria by triboelectric charge attraction and kill them by oxygen released from oxyhemoglobin. This phenomenon has been named oxycytosis by analogy with the term phagocytosis. Oxycytosis has been discussed in a number of published articles, but the specific mechanism of triboelectric charging and the mechanism of killing bacteria by oxidation, have not yet been detailed. The purpose of this review is to provide a more detailed explanation of the process of triboelectric charging and capture of bacteria by erythrocytes and destruction of bacteria by oxidation. For the first time, the review presents various variants of oxycytosis (two-stage, three-stage, multi-stage), depending on the resistance of the pathogen to oxidation. The review also discusses the biological significance of oxycytosis and its impact on the understanding of bacteremia and sepsis.

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Abstract

As antimicrobial resistance poses a globally rising health problem, the identification of alternative antimicrobial agents is urgently required. The short chain fatty acid propionate which is physiologically produced by the gut microbiota constitutes a promising molecule given that it has been widely used as a cosmetics and food preservative due to its antimicrobial effects. This literature survey aims to determine the most recent state of knowledge about the antimicrobial and immune-modulatory properties of propionate. Both in vitro and in vivo studies published between 2011 and 2020 confirmed the ability of propionate to inhibit the growth of several cellular pathogens, including Gram-positive and Gram-negative multi-drug resistant bacteria and fungi. In addition, heterogenous immune-modulatory and in particular, anti-inflammatory effects of propionate could be assessed involving a diverse signaling network that needs further comprehension. In conclusion, our literature survey provides evidence that propionate displays a plethora of health-beneficial including antimicrobial and immune-modulatory effects. Future research is required to further unravel the underlying molecular mechanisms and to set the basis for in vivo infection and clinical studies to broaden the path of propionate as a promising adjunct antibiotics-independent option in the combat of infections caused by multi-drug resistant bacteria.

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Acrolejeunea aulacophora (Mont.) Steph. is recorded for the first time in Asia. It was earlier known from Africa, Australia and New Caledonia. A detailed description with figures and a photographic plate is provided.

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Drepanolejeunea clavicornis and D. friesii were previously synonymised with D. physaefolia or all of them with D. vesiculosa. In the meantime, Drepanolejeunea vandenberghenii was described from the same species group, as new. In this paper many African specimens are compared with the original descriptions of the above species. Morphological investigations of these and their distributional patterns suggested that the former synonymisation was not justified. In addition, a new, rheophytic species from the same group: Drepanolejeunea vanderpoortenii, is described, as new to science. As a result, from the taxa related to Drepanolejeunea vesiculosa, now six species are recognised from Africa, including its Indian Ocean islands. For these 6 morphotaxa an identification key is provided. The results need confirmation by a future molecular analysis.

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Acta Botanica Hungarica
Authors: K. T. Kiss, Zs. Trábert, and M. Duleba
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A new species similar to Bryocrumia vivicolor, the only known species in the genus Bryocrumia, is described as Bryocrumia malabarica spec. nova from the Malabar Wildlife Sanctuary in the Western Ghats of Kerala in Peninsular India. It resembles Homalia in external appearance and was collected in a rheophytic habitat along a stream channel in the evergreen forest. The new species is characterised by closely arranged leaves with distinct tricostate, ovate-rounded to truncate leaves, upper margin of leaf rounded with fine serrations and an inconspicuous central strand in stem cross section.

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Acta Botanica Hungarica
Authors: S. Y. Kondratyuk, L. P. Popova, O. Y. Khodosovtsev, L. Lőkös, N. M. Fedorenko, and N. V. Kapets

The “Fourth checklist of lichen-forming and lichenicolous fungi of Ukraine”, including 2150 accepted scientific names based on published records as well as analysis of current additions are provided. Current additions include 439 taxa newly recorded for Ukraine after the third checklist of lichens of Ukraine by and 262 nomenclatural novelties. Annotations to each taxon of 318 newly recorded to Ukraine are provided in the style of the second checklist by Kondratyuk et al. (1998), i.e. data on phytogeographical regions and administrative districts (oblasts) of Ukraine as well as references to published papers are provided. Among current additions 99 taxa were annotated in the Checklist of lichenicolous fungi of Ukraine by Darmostuk and Khodosovtsev (2017) and consequent references to the latter are provided.

The conclusion confirms the earlier recommendation that national checklists of lichens are to be re-published more often than once a decade.

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Cytogenetic studies on four species of vascular coastal and water plants from Russian Far East are presented. During the present investigation the next chromosome numbers have been revealed: Gypsophila pacifica (2 n = 34), Allium sacculiferum (2 n = 32), Mertensia maritima (2 n = 24), and Nelumbo komarovii (2 n = 16). Unusual chromosome numbers for these species have not been noted but it was the first case of karyological studies of Nelumbo komarovii from the Jewish Autonomous Region and most northern habitat. The number of nucleoli in interphase nuclei of these species was counted. Interphase nuclei of studied species contain 1–4 nucleoli except in A. sacculiferum so far which have 1–2 nucleoli per cell. Different points of view on polyploidy of studied species are discussed.

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Hydroxycitric acid made the genus Garcinia economically important. Genetic and chemical diversity has been studied in Garcinia species using molecular markers, HCA and antioxidant activity. Nine species were collected and screened for molecular diversity and six were subjected to analyse antioxidant and HCA content and its interspecies variability. A total of 129, 125 and 89 bands with polymorphism of 78.74%, 78.4% and 93.36% were obtained using ISSR, RAPD and EST-SSR, respectively. The average PIC value obtained with ISSR, RAPD and EST-SSR markers was 0.9161, 0.9440 and 0.8903, respectively. Determined HCA content by HILIC-HPLC system using 0.1% orthophosphoric acid and acetonitrile (30:70) as mobile phase in fruit powder of various Garcinia species was found to be significantly different. G. gummi-gutta, G. indica and G. xanthochymus are rich of HCA containing 12.44±1.04%, 7.92±0.83% and 6.3±0.286%, respectively. G. morella, G. talbotii and G. celebica contained very negligible amount of HCA, 0.023±0.012%, 0.083±0.034% and 0.34±0.013%, correspondingly. G. talbotii showed high antioxidant capacity (95.40±0.720). Below that G. indica and G. xanthochymus were showing significant amount of total phenols (1.23±0.015 and 1.07±0.008), flavonoids (11.17±0.075 and 12.35±0.219) and antioxidant activity (90.73±0.976 and 91.37±0.854). Correlation analysis found significant association between molecular and chemical variation indicating influence of genetic background on the observed HCA and antioxidant profiles. The conducted analysis showed the most distinct species at the genetic and chemical levels were G. gummi-gutta, G. indica and G. xanthochymus. This study signifies the utility of molecular and chemical fingerprints for commercial exploitation of HCA from Garcinia species.

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Genetic relationships among 24 genotypes of Hyophila involuta collected from five different natural populations of Mount Abu (Rajasthan) is analysed using RAPD and SSR markers. Based on efficiency parameters calculated for each marker system such as polymorphic information content (RAPD = 0.34; SSR = 0.66), marker index (RAPD = 2.78; SSR = 2.62) and resolving power (RAPD = 8.13; SSR = 2.23), the RAPD marker system shows higher values for some indices but microsatellites are more accurately reproducible than RAPD. Moreover, in case of the SSR, the average number of alleles was almost twice compared to RAPD. Mean coefficient of genetic differentiation between populations with RAPD was Gst = 0.269, while with SSR marker was Fst = 0.224. The UPGMA cluster analysis assembled genotypes into two main clusters with diverse levels of sub-clustering within the clusters. Also, the Mantel test showed no significant correlation between geographical and genetic distances. The observed moderately high genetic variability can be explained by efficient spore dispersal. Other factors such as reproductive mode, somatic mutation, continuous propagule recruitment and high degree of intermingling have great impact on the level of genetic variability in moss populations.

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