Authors:Sadhana Roy, Debika Ghatak, Payel Das and Somdeb BoseDasgupta
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.
Authors:Minnja S. Hartmann, Soraya Mousavi, Stefan Bereswill and Markus M. Heimesaat
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.
Authors:G. K. Mishra, D. K. Upreti, S. Nayaka, A. Thell, I. Kärnefelt, L. Lőkös, J.-S. Hur, G. P. Sinha and S. Y. Kondratyuk
The present study recorded 36 genera and 115 species of the lichen family Teloschistaceae in India. Three species, i.e. Caloplaca rajasthanica S. Y. Kondr., Upreti et G. P. Sinha, Huriella upre- tiana S. Y. Kondr., G. K. Mishra, Nayaka et A. Thell, and Squamulea uttarkashiana S. Y. Kondr., Upreti, Nayaka et A. Thell, are described as new species. Seven new combinations, i.e. Fulgo- gasparrea awasthii (Y. Joshi et Upreti) S. Y. Kondr., Upreti et A. Thell, Neobrownliella cinnabarina (Ach.) S. Y. Kondr., Upreti et A. Thell, Neobrownliella holochracea (Nyl.) S. Y. Kondr., Upreti et A. Thell, Opeltia flavorubescens (Huds.) S. Y. Kondr. et J.-S. Hur, Oxneriopsis bassiae (Willd. ex Ach.) S. Y. Kondr., Upreti et J.-S. Hur, Upretia hueana (B. de Lesd.) S. Y. Kondr. et Upreti and Megaspora subpoliotera (Y. Joshi et Upreti) S. Y. Kondr., Upreti et A. Thell, are proposed based on nrITS phylogeny in the Teloschistaceae and Megasporaceae consequently. Validation of combination Olegblumia demissa is provided. Molecular data on Fulgogasparrea awasthii andMegaspora subpoliotera are recorded from India for the first time. Four new genera including one species each, i.e. Lazarenkoiopsis ussuriensis (Oxner, S. Y. Kondr. et Elix) S. Y. Kondr., L. őkö et J.-S. Hur, Mikhtomia gordejevii (Tomin) S. Y. Kondr., Kärnefelt, Elix, A. Thell, J. Kim, A. S. Kondratiuk et J.-S. Hur, Olegblumia demissa (Flot.) S. Y. Kondr., L. őkö, J. Kim, A. S. Kond- ratiuk, S.-O. Oh et J.-S. Hur and Pachypeltis intrudens (H. Magn.) Sochting Froden et Arup, as well as the genus Megaspora are reported as new for the Indian lichen biota.
Out of the eight lichenogeographical regions of India, the Western Himalayas show the maximum diversity of Teloschistaceae members represented with 110 species followed by the Central Indian region with 38 species. The lichen genus Caloplaca is represented with 50 species in the country followed by Athallia and Rusavskia with 6 species each. The saxi- colous taxa exhibit dominance with 65 species whereas the corticolous and terricolous taxa are represented by 48 and 9 species, respectively. Among the different states of India, Ut- tarakhand showed the maximum diversity represented by 54 species followed by the state of Jammu & Kashmir with 37 species, whereas the Jharkhand and Meghalaya states are represented only by the occurrence of a single species each. A key to the genera and species together with the description, basionyms and synonyms of each species are provided.
Authors:S. Y. Kondratyuk, L. Lőkös, S.-O. Oh, T. O. Kondratiuk, I. Yu. Parnikoza and J.-S. Hur
Fourteen species new for science are described, illustrated and compared with closely related taxa. Six species of them are from South Korea, i.e. Bryostigma huriellae S. Y. Kondr. et J.-S. Hur, Caloplaca ulleungensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Enterographa dokdoensis S. Y. Kondr. et J.-S. Hur, Neobrownliella salyangensis S. Y. Kondr. et J.-S. Hur, Rufoplaca aesan- ensis S. Y. Kondr. et J.-S. Hur, Squamulea coreana S. Y. Kondr. et J.-S. Hur, and seven species are from Chile: Caloplaca nothocitrina S. Y. Kondr. et J.-S. Hur, Caloplaca nothoholocarpa S. Y. Kondr. et J.-S. Hur, Caloplaca patagoniensis S. Y. Kondr., S.-O. Oh et J.-S. Hur, Follmannia suborthoclada S. Y. Kondr. et J.-S. Hur, ‘Lecidea’buellielloides S. Y. Kondr. et J.-S. Hur, Mass- jukiella rusavskioides S. Y. Kondr. et J.-S. Hur, Rehmanniella poeltiana S. Y. Kondr. et J.-S. Hur, as well as one species, i.e. Pyrenodesmia vernadskiensis S. Y. Kondr., T. O. Kondratiuk et I. Yu. Parnikoza, similar to Antarctic endemic species Huea coralligera, is from Argentine Islands, Western Antarctic Peninsula. The member of the genus Pyrenodesmia A. Massal. is for the first time confirmed by molecular data from the Antarctic.
Eighteen new combinations, i.e. Massjukiella impolita (for Caloplaca impolita Arup), Massjukiella pollinarioides (for Xanthoria pollinarioides L. Lindblom et D. M. Wright), Massjukiella stellata (for Caloplaca stellata Wetmore et Karnefelt), Massjukiella tenax (for Xanthoria tenax L. Lindblom), and Massjukiella tenuiloba (for Xanthoria tenuiloba L. Lindblom), Pyrenodesmia albopruinosa (for Biatorina albopruinosa Arnold), Pyrenodesmia ceracea (for Caloplaca ceracea J. R. Laundon), Pyrenodesmia cretensis (for Blastenia cretensis Zahlbr.), Pyrenodesmia erythrocarpa (for Patellaria erythrocarpa Pers.), Pyrenodesmia haematites (for Lecanora haematitesChaub. ex St.-Amans), Pyrenodesmia percrocata (for Blastenia percrocata Arnold), Pyrenodesmia soralifera (for Caloplaca soralifera Vondrak et Hrouzek), Pyrenodesmia transcaspica (for Lecanora transcaspica Nyl.), Pyrenodesmia viridirufa (for Lecidea viridirufa Ach.), Pyrenodesmia xerica (for Caloplaca xerica Poelt et Vezda), as well as Rehmanniella leucoxantha (for Amphilo-ma leucoxanthum Mull. Arg.), Rehmanniella syvashica (for Caloplaca syvashica Khodos., Vond- rak et Soun), and Rehmanniella subgyalectoides (for Caloplaca subgyalectoides S. Y. Kondr. et Karnefelt) are proposed.
Buelliella inops and Zwackhiomyces aff. berengerianus are for the first time recorded from South America as well as from Follmannia orthoclada (as lichenicolous fungi). Caloplaca poliotera, Rinodina convexula and Rinodina kozukensis are new to the Republic of Korea, and new localities as well as illustrations for the further 13 new and rare lichen species recently described from Eastern Asia are provided too.
Examination of about one hundred unidentified Colura specimens resulted in new distributional data of eleven uncommon species, C. australiensis, C. bicornis, C. calyptrifolia, C. crispiloba, C. cristata, C. heimii, C. humbertii, C. imperfecta, C. obesa, C. rhynchophora, C. saroltae and a new species of sect. Colura from Madagascar, C. cataractarum.
Authors:Matthias Halfter, Ulrich Müseler, Ralf Matthias Hagen and Hagen Frickmann
The study was performed to assess the infection risk of German police officers on predominantly tropical deployments, mostly United Nations missions, with gastrointestinal pathogens.
Police officers were offered PCR-based screening for gastrointestinal pathogens before and after deployment. The screening panel comprised enteroinvasive bacteria (Salmonella spp., Shigella spp./enteroinvasive Escherichia coli, Campylobacter jejuni, and Yersinia spp.), enteropathogenic protozoa (Entamoeba histolytica, Giardia duodenalis, Cryptosporidium spp., and Cyclospora cayetanensis), as well as enteric helminths (Ancyclostoma spp., Ascaris lumbricoides, Enterobius vermicularis, Hymenolepis nana, Necator americanus, African Schistosoma spp., Strongyloides stercoralis, Taenia saginata, Taenia solium, and Trichuris trichiura).
G. duodenalis (n = 3), C. jejuni (n = 2), Salmonella spp. (n = 1), Shigella spp./enteroinvasive E. coli (n = 3), and S. stercoralis (n = 3) were detect in 12 out of 133 (9.0%) police officers. The majority had shown gastrointestinal symptoms on deployment and all were asymptomatic at the time of medical assessment. The major infection sites were Sub-Saharan Africa followed by Northern Africa and the Middle East.
Deployment of police officers to tropical deployment sites on United Nations missions is associated with a considerable acquisition risk of gastrointestinal pathogens in a quantitatively relevant minority. Post-deployment screening is advisable to facilitate therapeutic and hygiene-related consequences.
To have a successful publication in a peer-reviewed journal, a collection of factors and items is needed. Some of them directly and the others indirectly have important roles in scholarly publication. However, a well-designed scientific investigation together with a powerful academic English language may guarantee the publication of a manuscript. In other words, a standard and professional methodology which is expressed by an influent academic English language constitutes the soul of the manuscript's body. Obviously, the accuracy and fluency of the English language of the manuscript is the author(s)' responsibility and neither the reviewers' nor the editor's and the journal's. As publication of a research paper is the complementary section of a scientific study, it is recognized as an academic criterion for academicians. Thus, this review focuses on the all of items which are necessary and vital for a successful scholarly publication.
Authors:Anja Dörschug, Julian Schwanbeck, Andreas Hahn, Anke Hillebrecht, Sabine Blaschke, Uwe Groß, Markus M. Heimesaat, Hagen Frickmann and Andreas E. Zautner
To efficiently monitor the COVID-19 pandemic for surveillance purposes, reliable serological rapid diagnostic tests (RDTs) are desirable for settings where well-established high-throughput bench-top solutions are not available. Here, we have evaluated such an RDT.
We have assessed the Xiamen AmonMed Biotechnology COVID-19 IgM/IgG test kit (Colloidal gold) and the EUROIMMUN benchtop assay with serum samples from patients with polymerase chain reaction (PCR)-confirmed COVID-19 disease. Samples from patients with Epstein-Barr-virus (EBV) infection and blood donors were used for specificity testing.
For the colloid gold rapid test and the EUROIMMUN assay, the study indicated overall sensitivity of 15.2% and 67.4%, respectively, while specificity of 99.0% and 97.9% with the blood donor sera, as well as 100% and 96.8% with the EBV-patients, were observed, respectively. An association of the time period between positive PCR results and serum acquisition with serological test positivity could be observed for the immunologlobulin G subclass of the EUROIMMUN assay only.
In spite of acceptable specificity of the assessed RDT, the detected poor sensitivity leaves room for improvement. The test results remain difficult to interpret and therefore the RDT can currently not be recommended for routine diagnostic or surveillance use.
Authors:Rasmus G. Bandick, Soraya Mousavi, Stefan Bereswill and Markus M. Heimesaat
Infections with multi-drug resistant (MDR) bacteria including carbapenem-resistant Klebsiella pneumoniae are emerging worldwide but are difficult to treat with the currently available antibiotic compounds and therefore constitute serious threats to human health. This prompted us to perform a literature survey applying the MEDLINE database and Cochrane Register of Controlled Trials including clinical trials comparing different treatment regimens for infections caused by carbapenem-resistant K. pneumoniae. Our survey revealed that a combined application of antibiotic compounds such as meropenem plus vaborbactam, meropenem plus colistin and carbapenem plus carbapenem, resulted in significantly increased clinical cure and decreased mortality rates as compared to respective control treatment. However, further research on novel antibiotic compounds, but also on antibiotic-independent molecules providing synergistic or at least resistance-modifying properties needs to be undertaken in vitro as well as in large clinical trials to provide future options in the combat of emerging life-threatening infections caused by MDR bacteria.
Authors:Dorothea Wiemer, Norbert Georg Schwarz, Gerd-Dieter Burchard, Hagen Frickmann, Ulrike Loderstaedt and Ralf-Matthias Hagen
Diarrhoea is a frequent symptom associated with travelling to tropical regions, but the cause is often not found. Epidemiology was assessed including up-to-date real-time PCR approaches.
We analysed datasets of 528 patients who presented at the Bernhard Nocht Institute for Tropical Medicine in Hamburg, Germany, between 2006 and 2010 for screening purposes or because of diarrhoea. Stool samples were obtained and investigated by microscopy, bacterial culture, two PCR assays targeting Entamoeba histolytica, Entamoeba dispar, Giardia duodenalis, and Cryptosporidium parvum, or Salmonella spp., Shigella/EIEC spp., Campylobacter jejuni, and Yersinia spp.
Among patients with gastrointestinal symptoms, 51% tested positive for bacteria or parasites, of which 66% had a known enteropathogenic potential. In patients without diarrhoea, 53% (n = 80) were positive, and 33% of these cases harboured agents of pathogenic potential. Association with clinical symptoms was primarily found for bacterial infections. Blastocystis hominis, however, was more frequent in asymptomatic than in symptomatic travellers.
In conclusion, the study stresses the etiological relevance of bacterial gastroenteritis in travellers returning from the tropics, the need for molecular approaches to increase diagnostic sensitivity and demonstrates that asymptomatic carriage of enteropathogens after prolonged stays in the tropics is similarly frequent compared with symptomatic infections in travellers.