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A new species (Rotundabaloghia (Circobaloghia)nagyi sp. nov.) of the rotundabaloghid mites is described based on females and male collected in bamboo leaf litter in Cameroon. The new species differs from the other Afrotropical rotundabaloghid mites in following character combination: female genital shield with long apical process, the setae v7 and v8 long and pilose, v6 long and smooth, v2 short and needle-like, female genital, dorsal and ventral shields are ornamented by irregular pits, sternal setae short and needle-like. This character combination is unknown within the African rotundabaloghids.

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Chañar (Geoffroea decorticans- Fabaceae) is a tree from South America that is normally infected with galls originated by insects. One of its parasites is Allodiplosis crassa (Cecidomyiidae, Diptera) which produces globular galls with sticky prolongations. Since this plant has medicinal uses in Argentina, its infestation could alter the quality of the plant drug. The surface of insect-induced galls usually contains defensive features such as trichomes, increased hardness and an increase in the content of polyphenolic compounds. The objective of this research is to assess the structural and histochemical features of the gall and to compare the content of polyphenolic metabolites in the gall, in the healthy leaf and in lignified stems of G. decorticans. The methanolic extract from the galls showed the highest amount of polyphenolic and proanthocyanidins and the lowest amount of hydroxycinnamic derivatives and flavonoids compared to the methanolic extract of the leaves. The photographs taken from the external surface of the gall showed that some prolongations have heads. The histochemical analysis showed that the prolongations have a high amount of proanthocyanidins and flavonoids; and that the heads are reactive to Sudan III. These phytochemical and histological characteristics may have a defensive role against harmful fungi and parasites that attack the larvae of the A. crassa. The results of this study show the presence of defensive features in an insect-induced gall of a medicinal plant with potential implications in the pharmacological activity of this species. This is the first report of a histochemical and phytochemical study in G. corticans galls.

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Whiteflies are the most important pests of economic crops in Egypt causing huge damage to them by their direct feeding, formation of sooty mold on plants and vectoring of plant viruses. An updated list of the 25 species of whiteflies (Hemiptera: Aleyrodidae) known to occur in Egypt and an identification key are provided.

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Abstract

Introduction

Surrogate endpoints are widely used in clinical trials, especially in situations where the endpoint of interest is not directly observable or to avoid long trial periods. A typical example for this case is frequently found in clinical trials in oncology, where overall survival (OS) as endpoint of interest and progression free survival (PFS) as surrogate endpoint are discriminated.

Methods

Based on the perspective of case definitions on surrogate endpoints, we provide a formal definition of such endpoints followed by a description of the structure of surrogate endpoints.

Results

Surrogate endpoints can be considered as case definitions for the endpoint of interest. Therefore, the performance of surrogate endpoints can be described using the classical terminology of diagnostic tests including sensitivity and specificity. Since such endpoints always focus on sensitivity with necessarily reduced specificity, efficacy estimates based on such endpoints are in general biased.

Conclusion

The abovementioned has to be taken into account while interpreting the results of clinical trials and should not be ignored while planning or conducting a study.

Open access

Abstract

Introduction

The aim of the study was a comparative evaluation of in-house real-time PCR and commercial real-time PCR (Fast Track Diagnostics (FTD), ampliCube/Mikrogen) targeting enteropathogenic bacteria from stool in preparation of Regulation (EU) 2017/746 on in vitro diagnostic medical devices.

Methods

Both 241 stool samples from patients and 100 samples from German laboratory control schemes (“Ringversuche”) were used to comparatively assess in-house real-time PCR, the FTD bacterial gastroenteritis kit, and the ampliCube gastrointestinal bacterial panels 1&2 either with the in-house PCRs as gold standard and as a test comparison without gold standard applying latent class analysis. Sensitivity, specificity, intra- and inter-assay variation and Cohen’s kappa were assessed.

Results

In comparison with the gold standard, sensitivity was 75–100% for strongly positive samples, 20–100% for weakly positive samples, and specificity ranged from 96 to 100%. Latent class analysis suggested that sensitivity ranges from 81.2 to 100% and specificity from 58.5 to 100%. Cohen’s kappa varied between moderate and nearly perfect agreement, intra- and inter-assay variation was 1–3 to 1–4 Ct values.

Conclusion

Acceptable agreement and performance characteristics suggested replaceability of the in-house PCR assays by the commercial approaches.

Open access

Abstract

Mycobacterium tuberculosis, the causative agent of Tuberculosis has plagued humankind for ages and has surfaced stronger than ever with the advent of drug resistance. Mycobacteria are adept at evading the host immune system and establishing infection by engaging host factors and secreting several virulence factors. Hence these secretion systems play a key role in mycobacterial pathogenesis. The type VII secretion system or ESX (early secretory antigenic target (ESAT6) secretion) system is one such crucial system that comprises five different pathways having distinct roles in mycobacterial proliferation, pathogenesis, cytosolic escape within macrophages, regulation of macrophage apoptosis, metal ion homeostasis, etc. ESX 1–5 systems are implicated in the secretion of a plethora of proteins, of which only a few are functionally characterized. Here we summarize the current knowledge of ESX secretion systems of mycobacteria with a special focus on ESX-1 and ESX-5 systems that subvert macrophage defenses and help mycobacteria to establish their niche within the macrophage.

Open access

Abstract

The use of antibiotics has provoked an emergence of various multidrug-resistant (MDR) bacteria. Infectious diseases that cannot be treated sufficiently with conventional antibiotic intervention strategies anymore constitue serious threats to human health. Therefore, current research focus has shifted to alternative, antibiotic-independent therapeutic approaches. In this context, vitamin E constitutes a promising candidate molecule due to its multi-faceted modes of action. Therefore, we used the PubMed database to perform a comprehensive literature survey reviewing studies addressing the antimicrobial properties of vitamin E against bacterial pathogens including MDR bacteria. The included studies published between 2010 and 2020 revealed that given its potent synergistic antimicrobial effects in combination with distinct antibiotic compounds, vitamin E constitutes a promising adjunct antibiotic treatment option directed against infectious diseases caused by MDR bacteria such as Pseudomonas aeruginosa, Burkholderia cenocepacia and methicillin-resistant Staphylococcus aureus (MRSA). In conclusion, the therapeutic value of vitamin E for the treatment of bacterial infections should therefore be investigated in future clinical studies.

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Acta Botanica Hungarica
Authors: K. T. Kiss, Zs Trábert, and M. Duleba
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Both the primary and secondary metabolisms of higher plants are influenced by environmental conditions. Peganum harmala L. synthesise amazing diversity of secondary metabolites, such as alkaloids, volatile oils, triterpenes or sterols. We have no detailed information on genetic chemical contents and particularly the fatty acid contents of this plant species in Iran. Therefore, population-based fatty acid and alkaloid analyses were conducted in four geographical populations. Seeds fatty acid analysis revealed linoleic acid, oleic acid and palmitic acid were the main components in seeds oil. The highest fatty acid component was the linoleic acid in both mature and premature seeds of four studied populations. Low levels of 18:3/18:2 ratio in mature seeds (>0.01) in comparison to premature seeds (> 0.04) were found. Grouping of the populations by WARD clustering, separated mature seeds from premature seeds. CCA plot of P. harmala populations based on fatty acid contents, revealing the influence of geographical features on population differentiation. The main alkaloid contents in premature and mature seeds were harmine and harmaline. PCoA plots of the studied populations based on alkaloid contents for both premature and mature seeds separated the populations from each other.

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Acta Botanica Hungarica
Authors: S. Y. Kondratyuk, L. Lőkös, M.-H. Jeong, S.-O. Oh, A. S. Kondratiuk, and J.-S. Hur

Three genera new for science, i.e. Candelinella S. Y. Kondr. for the Candelariella makarevichiae group, Opeltiella S. Y. Kondr. for the Candelaria fraudans group, as well as Protocandelariella Poelt, D. Liu, J.-S. Hur et S. Y. Kondr. for the Candelariella subdeflexa group are proposed for robust monophyletic branches of the Candelariaceae on the basis of three-gene phylo- geny (i.e. concatenated nrITS, 12S mtSSU and 28S nrLSU sequences). Eight new combinations, i.e. Candelinella makarevichiae (for Candelariella makarevichiae S. Y. Kondr., L. Lokos et J.-S. Hur), Candelinella deppeanae (for Candelariella deppeanae M. Westb.), Opeltiella fraudans (for Candelaria fraudans Poelt et Oberw.), Opeltiella fibrosoides (for Candelaria fibrosoides M. Westb. et Froden), Opeltiella rubrisoli (for Candelariella rubrisoli D. Liu et J.-S. Hur), Opeltiella canadensis (for Candelariella canadensis H. Magn.), Protocandelariella subdeflexa (for Lecanora subdeflexa Nyl.), Protocandelariella blastidiata (for Candelariella blastidiata L. Yakovchenko) are provided.

Molecular data provided for Candelinella makarevichiae (including holotype and iso- type), as well as additional specimens of Candelaria asiatica from South Korea for the first time. The latter species (Candelaria asiatica) from China, as well as’Candelaria’ murrayi from Argentina, South America are recorded for the first time. Voucher of Candelariella vitellina from Antarctica is also identified based on molecular phylogeny. It is for the first time shown that ’Candelaria’murrayi is positioned in the outermost position to Candelaria s. str. branch of the phylogenetic tree of the Candelariaceae, and may belong to another genus. Status of the ’Candelariella’medians group, the’Candelariella’ placodizans group, as well as single species ’Candelariella’reflexa and’Candelaria’ pacifica, forming separate branches outside the Candelariella s. str. and Candelaria s. str. clades, will be clarified when additional molecular data will be accumulated. Candelariella subsquamulosa D. Liu et Hur, recently described from South Korea (Liu et al. 2019), proved to be a new synonym of Candelinella makarevichiae.

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