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Mosquito control actions affect chironomid diversity in temporary wetlands of the Upper Rhine Valley
Kathrin Theissinger Nina Rder Stefanie Allgeier Arne J. Beermann Carsten A. Brühl Anna Friedrich Susanne Michiels Klaus Schwenk 《Molecular ecology》2019,28(18):4300-4316
The Upper Rhine Valley, a “hotspot of biodiversity” in Germany, has been treated with the biocide Bacillus thuringiensis var. israelensis (Bti) for mosquito control for decades. Previous studies discovered Bti nontarget effects in terms of severe chironomid abundance reductions. In this study, we investigated the impact of Bti on species level and addressed the community composition of the nontarget family Chironomidae by use of community metabarcoding. Chironomid emergence data were collected in three mosquito‐control relevant wetland types in the Upper Rhine Valley. For all three sites the chironomid species composition, based on operational taxonomic units (OTUs), was different to varying degrees in the Bti‐treated samples versus control samples, ranging from a significant 63% OTU reduction to an OTU replacement. We assumed that predatory chironomids are less prone to Bti than filter feeders, as the latter feed on floating particles leading to direct ingestion of Bti. However, a comparable percentage of predators and filter feeders (63% and 65%, respectively) was reduced in the Bti samples, suggesting that the feeding strategy is not the main driver for Bti sensitivity in chironomids. Finally, our data was compared to a three‐year‐old data set, indicating possible chironomid community recovery due to species recolonization a few years after the last Bti application. Considering the currently discussed worldwide insect decline we recommend a rethinking of the usage of the biocide Bti, and to prevent its ongoing application especially in nature protection reserves to enhance ecological resilience and to prevent boosting the current biodiversity loss. 相似文献
94.
Herpes simplex virus (HSV) is one of the most common, yet frequently overlooked, sexually transmitted infections. Since the type of HSV infection affects prognosis and subsequent counseling, type-specific testing to distinguish HSV-1 from HSV-2 is recommended. Although PCR has been the diagnostic standard for HSV infections of the central nervous system, until now viral culture has been the test of choice for HSV genital infection. However, HSV PCR, with its consistently and substantially higher rate of HSV detection, will likely replace viral culture as the gold standard for the diagnosis of genital herpes in people with active mucocutaneous lesions, regardless of anatomic location or viral type. Alternatively, type-specific serologic tests based on glycoprotein G should be the test of choice to establish the diagnosis of HSV infection when no active lesion is present. Given the difficulty in making the clinical diagnosis of HSV, the growing worldwide prevalence of genital herpes and the availability of effective antiviral therapy, there is an increased demand for rapid, accurate laboratory diagnosis of patients with HSV. 相似文献
95.
gnes Szilvs Anna Blzovics Gyrgy Szkely Elek Dinya Jnos Fehr Gyula Mzsik 《Journal of Physiology》2001,95(1-6):247-252
The tumorous processes, increased level of tumor markers and the change of free radical status are associated in patents with gastrointestinal tumors. The aim of this study was to examine free radical status and tumor markers in patients with gastrointestinal tumors. Two hundered and thirteen patients with gastrointestinal tumor were examined. In the control group 44 non-tumorous patients were examined. The tumor markers (CEA, CA 19-9, CA 72-4, AFP, TPA, AGP) and free radical status (total scavenger capacity) were diagnosed using venal blood (obtained by LIA-kits and chemiluminescent methods, LIA-mAT and the Lumat Berthold instrument). It has been found that: (1) The results showed that the tumor markers, TPA and AGP are the best indicators for the tumorous process; (2) The AGP serum level was in the operable case 91.56+/-38.29 mg/dl meanwhile its value was, 128.46+/-47.62 mg/dl (P<0.001) in the inoperable case; and (3) The TPA value was 118.37+/-155.47 mg/dl in the operable case, (P<0.001) while its value was 227.32+/-244.39 mg/dl in inoperable cases. The significantly high levels of the plasma Chemiluminescent Light Intensity (CLI)=28.12+/-25.96; was obtained in patients with rectal tumors vs. in the control cases CLI= 4.27+/-5.12 RLU% (Relative Light Unit; mean+S.D.; P<0.005). In six of these cases, the free radical status examination indicated the presence of the tumor, even though the level of tumor markers was normal. It has been concluded that the testing of both regular tumor markers and free radical status has an important role in the diagnosis and monitoring of the patients with gastrointestinal tumors. 相似文献
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Cavallini G Crippa A Magli MC Cavallini N Ferraretti AP Gianaroli L 《Biology of reproduction》2008,79(4):667-673
Interdependence between sperm concentration, motility, morphology, and the percentage of aneuploid sperm was explored to test whether oligoasthenoteratospermia (OAT) may have a multiple origin in idiopathic infertile males. A total of 174 men (age, 35.8 +/- 4.3 yr) with idiopathic infertility were studied. Seven patients had nonobstructive azoospermia, 55 had severe OAT, 30 had OAT, 27 had isolated alterations of motility, 45 had alterations of morphology and of motility, and 10 had isolated alterations of morphology. The sperm morphology was assessed with strict criteria. The percentage of aneuploid sperm was assessed with fluorescent in situ hybridization for chromosomes X, Y, 13, 15, 16, 17, 18, 21, and 22. Relationships between sperm features, and the relationship between sperm features and aneuploidies were analyzed with multivariate regression analysis. Statistical analysis did not find any significant relationship between the percentage of typical forms and sperm concentration or between morphology and motility. On the other hand, a positive and significant relationship was found between sperm concentration and motility. The percentage of aneuploid sperm was inversely and significantly related to the percentage of typical forms but not to motility and concentration. Sperm morphology is an independent characteristic with respect to concentration and motility, whereas it showed a significant inverse relationship with respect to the percentage of aneuploid sperm. This means that idiopathic OAT may occur by means of at least two independent pathways, the first affecting concentration and/or motility and the second affecting morphology. 相似文献
98.
Marcin Gr?zBo?ena Pawlikowska-Pawl?ga Anna Jarosz-Wilko?azka 《International biodeterioration & biodegradation》2011,65(1):124-129
When Abortiporus biennis was grown on PbO-amended media, Pb (II) ions accumulated near fungal membrane structures, in the cell wall, and in the cytoplasm of the fungal cells, and their presence caused cell vacuolization. Increased concentration of PbO in the growth media caused a decline in fungal accumulation capacity. Neither PbO solubilization nor an increased level of organic acids underneath the mycelium was found. 相似文献
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100.
Design and expression of peptides with antimicrobial activity against Salmonella typhimurium 下载免费PDF全文
Amalia Porta Anna Maria Petrone Silvana Morello Ilaria Granata Francesca Rizzo Domenico Memoli Alessandro Weisz Bruno Maresca 《Cellular microbiology》2017,19(2)
We showed previously that insertion of Synechocystis Δ12‐desaturase in salmonella's membrane alters membrane physical state (MPS), followed by the expression of stress genes causing inability to survive within murine macrophages (MΦ). Recently, we showed that expression of one membrane lipid domain (MLD) of Δ12‐desaturase (ORF200) interferes with salmonella MPS, causing loss of virulence in mice and immunoprotection. Here, we postulate that an α‐antimicrobial peptide (α‐AMP) intercalates within membrane lipids, and depending on its amino acid sequence, it does so within specific key sensors of MLD. In this study, we choose as target for a putative synthetic AMP, PhoP/PhoQ, a sensor that responds to low Mg2+ concentration. We synthesised a modified DNA fragment coding for an amino acid sequence (NUF) similar to that fragment and expressed it in salmonella typhimurium. We showed that the pattern of gene expression controlled by PhoP/PhoQ highlights dysregulation of pathways involving phospholipids biosynthesis, stress proteins and genes coding for antigens. RNA‐Seq of strain expressing ORF200 showed that the pattern of those genes is also altered here. Accumulation of NUF conferred temporary immunoprotection. This represents a powerful procedure to address synthetic α‐AMPs to a specific MLD generating live non‐virulent bacterial strains. 相似文献