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1.
Hundred strains of fungi were isolated from 48 packets of Greek cigarettes. They were:Aspergillus (28 strains),Penicillium (22),Mucor (18),Alternaria (14),Cladosporium (1),Streptomyces (4),Candida (11) andGeotrichum (2). From 55 packets of cigarettes manufactured outside of Greece other 100 strains of fungi were isolated and identified asAspergillus (35),Penicillium (23),Mucor (10),Alternaria (13),Cladosporium (5),Streptomyces (4),Candida (3),Geotrichum (1),Cephalosporium (2) andScopulariopsis (4).Results of the present study are discussed in relation to the mycological flora of the air in Athens and to the coli-aerogenes bacteria of cigarettes.
Résumé Les auteurs ont isolé 100 souches de champignons à partir de 48 paquets de cigarettes préparées en Grèce. Ces souches étaient identifiées commeAspergillus (28 souches),Penicillium (22),Mucor (18),Alternaria (14),Cladosporium (1),Streptomyces (4),Candida (11) etGeotrichum (2). D'autre part on a isolé 100 souches de champignons à partir de 55 paquets de cigarettes préparées à l'étranger (surtout aux Etats-Unis et en Angleterre). Ces souches étaientAspergillus (35),Penicillium (23),Mucor (10),Alternaria (13),Cladosporium (5),Streptomyces (4),Candida (3),Geotrichum (1),Cephalosporium (2) etScopulariopsis (4).Les résultats sont discutés en relation avec la flore mycosique de l'air à Athènes et les bactéries coliformes rétrouvées dans les cigarettes préparées en Grèce.相似文献
2.
Karayanni H Christaki U Van Wambeke F Dalby AP 《Journal of microbiological methods》2004,56(3):349-358
Ciliated protozoa are potential grazers of primary and bacterial production and act as intermediaries between picoplankton and copepods and other large suspension feeders. Accurate determination of ciliate abundance and feeding mode is crucial in oceanic carbon budget estimations. However, the impact of different fixatives on the abundance and cell volume of ciliates has been investigated in only a few studies using either laboratory cultures or natural populations. Lugol's solution and formalin are the most commonly used fixatives for the preservation of ciliates samples. In the present study, the aim was to compare 0.4% Lugol's solution and 2% borated-formalin fixation and evaluate the need of counting duplicate samples each using a different fixative. For this, a large number of samples (n = 110) from the NE Atlantic was analyzed in the frame of POMME program (Multidisciplinary Mesoscale Ocean Program). We established a statistically significant relationship (p < 0.0001) between Lugol's and formalin fixed samples for both abundance (r2 = 0.50) and biomass (r2 = 0.76) of aloricate ciliates which showed that counts were higher in Lugol's solution by a factor of 2 and a non-taxon specific cell-loss in formalin. However, loricate ciliate abundance in our samples which were represented primarily by Tintinnus spp. did not show any difference between the two treatments. Abundance and biomass of mixotrophic ciliates (chloroplast-bearing cells) were for various reasons underestimated in both treatments. Our results show that unique fixation by formalin may severely underestimate ciliates abundance and biomass although their population may not alter. For this reason, Lugol's solution is best for the estimation of their abundance and biomass. However, for counts of mixotrophs and the evaluation of the ecological role of ciliates in carbon flux, double fixation is essential. Compromises regarding the fixatives have lead to severe underestimations of mixotrophs in studies conducted by now. 相似文献
3.
The effect of inorganic particle concentrations on bacteria-virus-nanoflagellate dynamics in an oligotrophic coastal system was investigated using a model aluminosilicate, kaolinite, with a modal size of 2.1 μm. Virus-only, bacteria-only and bacteria-virus-nanoflagellate incubations were carried out at increasing kaolinite concentrations to elucidate the microbial response. The sorption of bacteria and viruses to kaolinite particles was negligible over a concentration range of 1-50 mg l(-1). In contrast, the abundance of heterotrophic nanoflagellates was negatively correlated with kaolinite concentrations following both 48 and 96 h incubations. Calculated nanoflagellate bacterial ingestion rates were reduced by 5-35% depending on kaolinite particle concentration. In the bacteria-virus-nanoflagellate incubations viral production increased by 56 × 10(3) to 104 × 10(3) VLPs ml(-1) h(-1) as a function of kaolinite particle concentration. Our results demonstrate for the first time that the interaction of microbial populations with inorganic particles can shift the balance between protist and virally mediated mortality of marine heterotrophic prokaryotes. 相似文献
4.
Budkowska A Kakkanas A Nerrienet E Kalinina O Maillard P Horm SV Dalagiorgou G Vassilaki N Georgopoulou U Martinot M Sall AA Mavromara P 《PloS one》2011,6(1):e15871
The biological role of the protein encoded by the alternative open reading frame (core+1/ARF) of the Hepatitis C virus (HCV) genome remains elusive, as does the significance of the production of corresponding antibodies in HCV infection. We investigated the prevalence of anti-core and anti-core+1/ARFP antibodies in HCV-positive blood donors from Cambodia, using peptide and recombinant protein-based ELISAs. We detected unusual serological profiles in 3 out of 58 HCV positive plasma of genotype 1a. These patients were negative for anti-core antibodies by commercial and peptide-based assays using C-terminal fragments of core but reacted by Western Blot with full-length core protein. All three patients had high levels of anti-core+1/ARFP antibodies. Cloning of the cDNA that corresponds to the core-coding region from these sera resulted in the expression of both core and core+1/ARFP in mammalian cells. The core protein exhibited high amino-acid homology with a consensus HCV1a sequence. However, 10 identical synonymous mutations were found, and 7 were located in the aa(99-124) region of core. All mutations concerned the third base of a codon, and 5/10 represented a T>C mutation. Prediction analyses of the RNA secondary structure revealed conformational changes within the stem-loop region that contains the core+1/ARFP internal AUG initiator at position 85/87. Using the luciferase tagging approach, we showed that core+1/ARFP expression is more efficient from such a sequence than from the prototype HCV1a RNA. We provide additional evidence of the existence of core+1/ARFP in vivo and new data concerning expression of HCV core protein. We show that HCV patients who do not produce normal anti-core antibodies have unusually high levels of anti-core+1/ARFP and harbour several identical synonymous mutations in the core and core+1/ARFP coding region that result in major changes in predicted RNA structure. Such HCV variants may favour core+1/ARFP production during HCV infection. 相似文献
5.
Marine Landa Stéphane Blain Urania Christaki Sébastien Monchy Ingrid Obernosterer 《The ISME journal》2016,10(1):39-50
Marine microbes have a pivotal role in the marine biogeochemical cycle of carbon, because they regulate the turnover of dissolved organic matter (DOM), one of the largest carbon reservoirs on Earth. Microbial communities and DOM are both highly diverse components of the ocean system, yet the role of microbial diversity for carbon processing remains thus far poorly understood. We report here results from an exploration of a mosaic of phytoplankton blooms induced by large-scale natural iron fertilization in the Southern Ocean. We show that in this unique ecosystem where concentrations of DOM are lowest in the global ocean, a patchwork of blooms is associated with diverse and distinct bacterial communities. By using on-board continuous cultures, we identify preferences in the degradation of DOM of different reactivity for taxa associated with contrasting blooms. We used the spatial and temporal variability provided by this natural laboratory to demonstrate that the magnitude of bacterial production is linked to the extent of compositional changes. Our results suggest that partitioning of the DOM resource could be a mechanism that structures bacterial communities with a positive feedback on carbon cycling. Our study, focused on bacterial carbon processing, highlights the potential role of diversity as a driving force for the cycling of biogeochemical elements. 相似文献
6.
Frequent genes in rare diseases: panel‐based next generation sequencing to disclose causal mutations in hereditary neuropathies 下载免费PDF全文
Maike F. Dohrn Nicola Glöckle Lejla Mulahasanovic Corina Heller Julia Mohr Christine Bauer Erik Riesch Andrea Becker Florian Battke Konstanze Hörtnagel Thorsten Hornemann Saranya Suriyanarayanan Markus Blankenburg Jörg B. Schulz Kristl G. Claeys Burkhard Gess Istvan Katona Andreas Ferbert Debora Vittore Alexander Grimm Stefan Wolking Ludger Schöls Holger Lerche G. Christoph Korenke Dirk Fischer Bertold Schrank Urania Kotzaeridou Gerhard Kurlemann Bianca Dräger Anja Schirmacher Peter Young Beate Schlotter‐Weigel Saskia Biskup 《Journal of neurochemistry》2017,143(5):507-522
7.
Ioanna M. Spyrou Dimitrios G. Karpouzas Urania Menkissoglu-Spiroudi 《Microbial ecology》2009,58(4):715-727
The effects of synthetic pesticides on the soil microbial community have been thoroughly investigated in the past mostly by
culture-dependent methods and only few recent studies have used culture-independent approaches for this purpose. However,
it should be noted that most of these studies have been conducted in microcosms where the soil microbial community is exposed
to unrealistic concentrations of the pesticides, providing an unrealistic exposure scheme for soil microorganism. On the other
hand, little is known regarding the potential impact of botanical pesticides on the soil microbial community. Therefore, a
laboratory study and a field study were conducted to investigate the effects of synthetic (metham sodium [MS], sodium tetrathiocarbonate
[SoTe], and fosthiazate) and botanical pesticides (azadirachtin, quillaja, and pulverized Melia azedarach fruits [PMF]) on the soil microbial community using phospholipid fatty acids (PLFA) analysis. Principal component analysis
(PCA) on the results of the laboratory study indicated that the application of PMF resulted in significant changes in the
soil microbial community. This was obvious by the proportional increase in the abundance of fatty acids 18:1ω9cis, 18:1ω9trans, which are common in gram-negative bacteria and saprotrophic fungi, and 18:2ω6,9, which is a fungal indicator. This response
was attributed to the release of copious amounts of organic carbon and nutrients in the soil by the PMF. On the other hand,
MS inhibited fungi and gram-negative bacteria, while fosthiazate and the botanical pesticides quillaja and azadirachtin did
not impose significant changes in the soil microbial community. Similar results were obtained by the field study where application
of the fumigants MS and SoTe significantly altered the structure of the soil microbial community with the former having a
more prominent effect. Fosthiazate imposed mild changes in the soil microbial community, whereas quillaja and azadirachtin
again did not show a significant effect. Overall, botanical pesticides, at their recommended dose, did not alter the structure
of the soil microbial community compared to synthetic nonfumigant and fumigant pesticides which induced significant changes. 相似文献
8.
The female genital tract (FGT) harbors very large numbers of bacterial species that are known to play an important role on
vaginal health. Previous studies have focused on bacterial diversity in the vagina, but little is known about the ectocervical
microbiota associated with FGT infections. In our study, vaginal swabs and ectocervical swabs were collected from 100 participants
in China, including 30 women with bacterial vaginosis (BV; BV group), 22 women with cervicitis (Cer group), 18 women with
BV in combination with cervicitis (BC group) and 30 healthy control women (CN group). The diversity and richness of cervicovaginal
microbiota were investigated with culture-independent polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis
(DGGE) and quantitative PCR (qPCR) targeting 11 microorganisms that have been associated with FGT infections. Despite significant
interpersonal variations, the PCR-DGGE profiles revealed that vaginal microbiota and ectocervical microbiota were clearly
much more complex in the BV group, while the ectocervical microbiota showed no significant difference between healthy and
diseased participants. Using species-specific qPCR, BV and cervicitis were significantly associated with a dramatic decrease
in Lactobacillus species (p < 0.05), and potential pathogenic species such as Gardnerella, Atopobium, Eggerthella, Leptotrichia/Sneathia, and Prevotella were more common and in higher copy numbers in BV than in CN samples (p values ranged from 0.000 to 0.021). No significant differences were observed between healthy and cervicitis samples (p > 0.05) in ectocervical microbiota. The total numbers of bacteria were significantly lower in the ectocervix as compared
in the vagina (p < 0.05). Intriguingly, vaginal microbiota from participants with BV in combination with cervicitis was quite different from
that of participants with BV or cervicitis alone. Our study demonstrated that the cervicovaginal microbiota was actively involved
in the process of FGT infections. The predominant bacteria of the cervicovaginal communities were clearly associated with
BV; however, there was not sufficient evidence that the ectocervical microbiota is directly involved in the development of
cervicitis. 相似文献
9.
Evidence for cellular uptake of recombinant hepatitis C virus non-enveloped capsid-like particles 总被引:1,自引:0,他引:1
Tsitoura P Georgopoulou U Pêtres S Varaklioti A Karafoulidou A Vagena D Politis C Mavromara P 《FEBS letters》2007,581(21):4049-4057
Although the hepatitis C virus (HCV) is an enveloped virus, naked nucleocapsids have been reported in the serum of infected patients, and most recently novel HCV subgenomes with deletions of the envelope proteins have been identified. However the significance of these findings remains unclear. In this study, we used the baculovirus expression system to generate recombinant HCV capsid-like particles, and investigated their possible interactions with cells. We show that expression of HCV core in insect cells can sufficiently direct the formation of capsid-like particles in the absence of the HCV envelope glycoproteins and of the 5' untranslated region. By confocal microscopy analysis, we provide evidence that the naked capsid-like particles could be uptaken by human hepatoma cells. Moreover, our findings suggest that they have the potential to produce cell-signaling effects. 相似文献
10.
Dimitrios Karussis Hagai Shor Julia Yachnin Naama Lanxner Merav Amiel Keren Baruch Yael Keren-Zur Ofra Haviv Massimo Filippi Panayiota Petrou Shalom Hajag Urania Vourka-Karussis Adi Vaknin-Dembinsky Salim Khoury Oded Abramsky Henri Atlan Irun R. Cohen Rivka Abulafia-Lapid 《PloS one》2012,7(12)