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1.
Animals (Basel) ; 13(7)2023 Mar 31.
Article in English | MEDLINE | ID: mdl-37048477

ABSTRACT

The bovine genital tract harbors a dynamic microbiome. Genital tract microbial communities in healthy animals have been characterized using next-generation sequencing methods showing that microbe compositions differ between the vagina and uterus, more so during the postpartum period. Pre-calving fecal and vaginal, and endometrial swabs at the different postpartum intervals were collected from dairy cows. Microbiomes in these samples were determined based on bacterial 16S amplicon sequencing and compared between healthy (H; n = 10) control animals and cows that developed metritis (M; n = 10) within 21 days postpartum (DPP). Compared to healthy animals the pre-calving fecal and vaginal microbiomes of metritis animals were more abundant in sequences from the phylum Fusobacteria and the bacterial genera such as Escherichia-Shigella and Histophilus. In addition, compared to healthy animals, metritis cows harboured low microbial species diversity in the endometrium, as well as decreasing Proteobacteria and increasing Fusobacteria, Firmicutes, Actinobacteria, and Bacteroidetes abundances. The greatest taxonomic compositional deviations in endometrial microbial communities between the metritis and health cows were detected between 7 and 10 DPP. There was high taxonomic similarity detected between postpartum endometrial microbiomes and the prepartum vaginal and fecal microbiomes suggesting that colonization through bacteria ascending from the rectum and vagina to the uterine cavity might play a major role in establishing the endometrial microbiome postpartum. A deeper understanding of the establishment and dynamics of postpartum endometrial microbial communities in cows will thus provide crucial basic knowledge to guide the development of genital microbiome manipulation strategies for preventing uterine disease and improving fertility in dairy cows.

2.
ACS Biomater Sci Eng ; 9(2): 1020-1029, 2023 02 13.
Article in English | MEDLINE | ID: mdl-36720461

ABSTRACT

We present the design, fabrication, and characterization of an implantable neural interface based on anisotropic magnetoresistive (AMR) magnetic-field sensors that combine reduced size and high performance at body temperature. The sensors are based on La0.67Sr0.33MnO3 (LSMO) as a ferromagnetic material, whose epitaxial growth has been suitably engineered to get uniaxial anisotropy and large AMR output together with low noise even at low frequencies. The performance of LSMO sensors of different film thickness and at different temperatures close to 37 °C has to be explored to find an optimum sensitivity of ∼400%/T (with typical detectivity values of 2 nT·Hz-1/2 at a frequency of 1 Hz and 0.3 nT·Hz-1/2 at 1 kHz), fitted for the detection of low magnetic signals coming from neural activity. Biocompatibility tests of devices consisting of submillimeter-size LSMO sensors coated by a thin poly(dimethyl siloxane) polymeric layer, both in vitro and in vivo, support their high suitability as implantable detectors of low-frequency biological magnetic signals emerging from heterogeneous electrically active tissues.


Subject(s)
Magnetic Fields , Prostheses and Implants , Anisotropy , Polymers
3.
Front Microbiol ; 13: 978296, 2022.
Article in English | MEDLINE | ID: mdl-35992704

ABSTRACT

The importance of acetogens for H2 turnover and overall anaerobic degradation in peatlands remains elusive. In the well-studied minerotrophic peatland fen Schlöppnerbrunnen, H2-consuming acetogens are conceptualized to be largely outcompeted by iron reducers, sulfate reducers, and hydrogenotrophic methanogens in bulk peat soil. However, in root zones of graminoids, fermenters thriving on rhizodeposits and root litter might temporarily provide sufficient H2 for acetogens. In the present study, root-free peat soils from around the roots of Molinia caerulea and Carex rostrata (i.e., two graminoids common in fen Schlöpnnerbrunnen) were anoxically incubated with or without supplemental H2 to simulate conditions of high and low H2 availability in the fen. In unsupplemented soil treatments, H2 concentrations were largely below the detection limit (∼10 ppmV) and possibly too low for acetogens and methanogens, an assumption supported by the finding that neither acetate nor methane substantially accumulated. In the presence of supplemental H2, acetate accumulation exceeded CH4 accumulation in Molinia soil whereas acetate and methane accumulated equally in Carex soil. However, reductant recoveries indicated that initially, additional unknown processes were involved either in H2 consumption or the consumption of acetate produced by H2-consuming acetogens. 16S rRNA and 16S rRNA gene analyses revealed that potential acetogens (Clostridium, Holophagaceae), methanogens (Methanocellales, Methanobacterium), iron reducers (Geobacter), and physiologically uncharacterized phylotypes (Acidobacteria, Actinobacteria, Bacteroidetes) were stimulated by supplemental H2 in soil treatments. Phylotypes closely related to clostridial acetogens were also active in soil-free Molinia and Carex root treatments with or without supplemental H2. Due to pronounced fermentation activities, H2 consumption was less obvious in root treatments, and acetogens likely thrived on root organic carbon and fermentation products (e.g., ethanol) in addition to H2. Collectively, the data highlighted that in fen Schlöppnerbrunnen, acetogens are associated to graminoid roots and inhabit the peat soil around the roots, where they have to compete for H2 with methanogens and iron reducers. Furthermore, the study underscored that the metabolically flexible acetogens do not rely on H2, potentially a key advantage over other H2 consumers under the highly dynamic conditions characteristic for the root-zones of graminoids in peatlands.

4.
FEMS Microbiol Ecol ; 97(11)2021 11 13.
Article in English | MEDLINE | ID: mdl-34718537

ABSTRACT

Fen Schlöppnerbrunnen is a moderately acidic methane-emitting peatland overgrown by Molinia caerulea and other wetland graminoids (e.g. Carex rostrata). Recently, the accumulation of H2, an indicator for fermentation, was observed with anoxically incubated C. rostrata roots but not with root-free fen soil. Based on this finding, we hypothesized that root-derived organic carbon has a higher capacity to promote fermentation processes than peat organic carbon from root-free fen soil. To address this hypothesis, C. rostrata and M. caerulea roots were anoxically incubated with or without fen soil and the product profiles of root treatments were compared with those of root-free soil treatments. Ethanol, acetate, propionate, butyrate, H2 and CO2 accumulated in root treatments and collective amounts of carbon in accumulating products were 20-200 times higher than those in root-free soil treatments, in which mainly CO2 accumulated. Analyses of 16S rRNA and 16S rRNA gene sequences revealed that Clostridium, Propionispira and Rahnella, representatives of butyrate, propionate and mixed acid fermenters, respectively, were relatively enriched in root treatments. In contrast, differences of the microbial community before and after incubation were marginal in root-free soil treatments. Collectively, these findings supported the assumed stimulatory effect of root-derived organic carbon on fen fermenters.


Subject(s)
Carbon , Methane , Carbon Dioxide , Fermentation , RNA, Ribosomal, 16S/genetics , Soil , Soil Microbiology
5.
Psychother Psychosom Med Psychol ; 71(9-10): 406-411, 2021 Oct.
Article in German | MEDLINE | ID: mdl-33915579

ABSTRACT

This article explains the development and implementation of a psychosomatic screening and consultation service for inpatient somatic care. Approximately one in six somatic inpatients has a mental disorder. It is estimated that only half of these cases are properly identified. Consequently, a large proportion of patients remains untreated. To address this gap in care, a psychosomatic early detection programme was developed by an interdisciplinary working group. This programme is based on the Patient Health Questionnaire-4 (PHQ-4), a psychometrically very well evaluated ultra-short screening questionnaire for the detection of depressive and anxiety disorders. For implementation in routine inpatient care, the PHQ-4 was programmed as a form in the electronic medical record and administered by nursing staff during the admission interview. If the PHQ-4 screening result indicates the presence of a mental comorbidity and the patient expresses a wish for assessment of this disorder, a psychosomatic consultation is automatically ordered. The PHQ-4 was implemented into the clinical routine in four internal medicine and three dermatology wards of the University Medical Center Hamburg-Eppendorf. Documentation of the early diagnosis in the electronic patient record is a minimally costly, less time-consuming and practicable method of providing patients with holistic care through rapid interdisciplinary referral. An evaluation of cost-effectiveness, clinical efficiency, and acceptance is still pending.


Subject(s)
Psychophysiologic Disorders , Referral and Consultation , Anxiety Disorders , Comorbidity , Early Diagnosis , Humans , Psychophysiologic Disorders/diagnosis , Psychophysiologic Disorders/epidemiology , Psychophysiologic Disorders/therapy
6.
Sci Rep ; 10(1): 15267, 2020 09 17.
Article in English | MEDLINE | ID: mdl-32943681

ABSTRACT

The genus Listeria comprises ubiquitous bacteria, commonly present in foods and food production facilities. In this study, three different phage display technologies were employed to discover targets, and to generate and characterize novel antibodies against Listeria: antibody display for biomarker discovery and antibody generation; ORFeome display for target identification; and single-gene display for epitope characterization. With this approach, pyruvate dehydrogenase complex-enzyme 2 (PDC-E2) was defined as a new detection target for Listeria, as confirmed by immunomagnetic separation-mass spectrometry (IMS-MS). Immunoblot and fluorescence microscopy showed that this protein is accessible on the bacterial cell surface of living cells. Recombinant PDC-E2 was produced in E. coli and used to generate 16 additional antibodies. The resulting set of 20 monoclonal scFv-Fc was tested in indirect ELISA against 17 Listeria and 16 non-Listeria species. Two of them provided 100% sensitivity (CI 82.35-100.0%) and specificity (CI 78.20-100.0%), confirming PDC-E2 as a suitable target for the detection of Listeria. The binding region of 18 of these antibodies was analyzed, revealing that ≈ 90% (16/18) bind to the lipoyl domains (LD) of the target. The novel target PDC-E2 and highly specific antibodies against it offer new opportunities to improve the detection of Listeria.


Subject(s)
Bacteriophages/immunology , Listeria/immunology , Pyruvate Dehydrogenase Complex/immunology , Amino Acid Sequence , Antibodies, Monoclonal/immunology , Antibody Specificity/immunology , Cell Surface Display Techniques/methods , Epitopes/immunology , Escherichia coli/immunology , Immunoblotting/methods , Peptide Library , Single-Chain Antibodies/immunology
7.
Appl Environ Microbiol ; 84(5)2018 03 01.
Article in English | MEDLINE | ID: mdl-29247057

ABSTRACT

The earthworm gut is an anoxic, saccharide-rich microzone in aerated soils. The apparent degradation of diverse saccharides in the alimentary canal of the model earthworm Lumbricusterrestris is concomitant with the production of diverse organic acids, indicating that fermentation is an ongoing process in the earthworm gut. However, little is known about how different gut-associated saccharides are fermented. The hypothesis of this investigation was that different gut-associated saccharides differentially stimulate fermentative microorganisms in gut contents of L. terrestris This hypothesis was addressed by (i) assessing the fermentation profiles of anoxic gut content microcosms that were supplemented with gut-associated saccharides and (ii) the concomitant phylogenic analysis of 16S rRNA sequences. Galactose, glucose, maltose, mannose, arabinose, fucose, rhamnose, and xylose stimulated the production of fermentation products, including H2, CO2, acetate, lactate, propionate, formate, succinate, and ethanol. Fermentation profiles were dependent on the supplemental saccharide (e.g., glucose yielded large amounts of H2 and ethanol, whereas fucose did not, and maltose yielded large amounts of lactate, whereas mannose did not). Approximately 1,750,000 16S rRNA sequences were affiliated with 37 families, and phylogenic analyses indicated that a respective saccharide stimulated a subset of the diverse phylotypes. An Aeromonas-related phylotype displayed a high relative abundance in all treatments, whereas key Enterobacteriaceae-affiliated phylotypes were stimulated by some but not all saccharides. Collectively, these results reinforce the likelihood that (i) different saccharides stimulate different fermentations in gut contents of the earthworm and (ii) facultative aerobes related to Aeromonadaceae and Enterobacteriaceae can be important drivers of these fermentations.IMPORTANCE The feeding habits of earthworms influence the turnover of elements in the terrestrial biosphere. The alimentary tract of the earthworm constitutes an anoxic saccharide-rich microzone in aerated soils that offers ingested microbes a unique opportunity for anaerobic growth. The fermentative activity of microbes in the alimentary tract are responsible for the in situ production of (i) organic compounds that can be assimilated by the earthworm and (ii) H2 that is subject to in vivo emission by the earthworm and can be trophically linked to secondary microbial events in soils. To gain insight on how fermentative members of the gut microbiome might respond to the saccharide-rich alimentary canal, this study examines the impact of diverse gut-associated saccharides on the differential activation of fermentative microbes in gut contents of the model earthworm L. terrestris.


Subject(s)
Bacteria/metabolism , Deoxy Sugars/metabolism , Disaccharides/metabolism , Gastrointestinal Microbiome , Monosaccharides/metabolism , Oligochaeta/microbiology , Animals , Bacteria/classification , Bacteria/isolation & purification , Fermentation , Oligochaeta/physiology , RNA, Bacterial/analysis , RNA, Ribosomal, 16S/analysis
8.
Front Microbiol ; 8: 397, 2017.
Article in English | MEDLINE | ID: mdl-28386248

ABSTRACT

Reduced susceptibility of Listeria monocytogenes to benzalkonium chloride (BC), a quaternary ammonium compound widely used in food processing and hospital environments, is a growing public health and food safety concern. The minimal inhibitory concentration of BC on 392 L. monocytogenes strains from Switzerland (CH) and Finland (FIN) was determined. Within this strain collection, benzalkonium chloride resistance was observed in 12.3% (24/195) of Swiss and 10.6% (21/197) of Finnish strains. In both countries, the highest prevalence of BC-resistant strains (CH: 29.4%; FIN: 38.9%) was detected among serotype 1/2c strains. Based on PCR analysis, genes coding for the qacH efflux pump system were detected for most of the BC-resistant strains (CH: 62.5%; FIN: 52.4%). Some Swiss BC-resistant strains harbored genes coding for the bcrABC (16.7%) efflux pump system, while one Finnish BC-resistant strain harbored the emrE gene previously only described among BC-resistant L. monocytogenes strains from Canada. Interestingly, a subset of BC-resistant strains (CH: 5/24, 20.8%; FIN: 9/21, 42.8%) lacked genes for efflux pumps currently known to confer BC resistance in L. monocytogenes. BC resistance analysis in presence of reserpine showed that the resistance was completely or partially efflux pump dependent in 10 out of the 14 strains lacking the known BC resistance genes. Sequence types 155 and ST403 were over-representated among these strains suggesting that these strains might share similar but yet unknown mechanisms of BC resistance.

9.
Hepatology ; 58(1): 31-42, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23213046

ABSTRACT

UNLABELLED: Chronic infection with the human hepatitis B virus (HBV) is a global health problem and a main cause of progressive liver diseases. HBV exhibits a narrow host range, replicating primarily in hepatocytes. Both host and hepatocyte specificity presumably involve specific receptor interactions on the target cell; however, direct evidence for this hypothesis is missing. Following the observation that HBV entry is specifically blocked by L-protein-derived preS1-lipopeptides, we visualized specific HBV receptor/ligand complexes on hepatic cells and quantified the turnover kinetics. Using fluorescein isothiocyanate-labeled, myristoylated HBV preS1-peptides we demonstrate (1) the presence of a highly specific HBV receptor on the plasma membrane of HBV-susceptible primary human and tupaia hepatocytes and HepaRG cells but also on hepatocytes from the nonsusceptible species mouse, rat, rabbit and dog; (2) the requirement of a differentiated state of the hepatocyte for specific preS1-binding; (3) the lack of detectable amounts of the receptor on HepG2 and HuH7 cells; (4) a slow receptor turnover at the hepatocyte membrane; and (5) an association of the receptor with actin microfilaments. The presence of the preS1-receptor in primary hepatocytes from some non-HBV-susceptible species indicates that the lack of susceptibility of these cells is owed to a postbinding step. CONCLUSION: These findings suggest that HBV hepatotropism is mediated by the highly selective expression of a yet unknown receptor* on differentiated hepatocytes, while species specificity of the HBV infection requires selective downstream events, e.g., the presence of host dependency or the absence of host restriction factors. The criteria defined here will allow narrowing down reasonable receptor candidates and provide a binding assay for HBV-receptor expression screens in hepatic cells.


Subject(s)
Hepatitis B virus/metabolism , Hepatocytes/metabolism , Receptors, Virus/metabolism , Viral Envelope Proteins/physiology , Animals , Cell Differentiation , Dogs , Fluorescein-5-isothiocyanate , Fluorescent Dyes , Hep G2 Cells , Hepatocytes/immunology , Humans , Kinetics , Mice , Myristic Acid/metabolism , Protein Precursors/metabolism , Rabbits , Rats , Species Specificity , Tupaia
10.
J Agric Food Chem ; 59(15): 8524-30, 2011 Aug 10.
Article in English | MEDLINE | ID: mdl-21707031

ABSTRACT

Phlorhizin interferes with glucose transport. Glucose depletion triggers suicidal erythrocyte death or eryptosis, characterized by cell shrinkage and cell membrane scrambling. Eryptosis is further triggered by oxidative stress. The present study explored whether phlorhizin influences eryptosis following glucose depletion or oxidative stress. Cell membrane scrambling was estimated from annexin binding, cell volume from forward scatter (FSC), and cytosolic Ca(2+) concentration from Fluo-3 fluorescence. Phlorhizin (10-100 µM) added alone did not modify scrambling, FSC, or Fluo-3 fluorescence. Glucose depletion (48 h) significantly increased Fluo-3 fluorescence, decreased FSC, and increased annexin binding, effects in part significantly blunted by phlorhizin (annexin binding ≥ 10 µM, FSC ≥ 50 µM). Oxidative stress (30 min 0.3 mM tert-butylhydroperoxide) again significantly increased Fluo-3 fluorescence and triggered annexin binding, effects again in part significantly blunted by phlorhizin (Fluo-3 fluorescence ≥ 50 µM, annexin-binding ≥ 10 µM). Phlorhizin did not blunt the cell shrinkage induced by oxidative stress. The present observations disclose a novel effect of phlorhizin, that is, an influence on suicidal erythrocyte death following energy depletion and oxidative stress.


Subject(s)
Erythrocyte Membrane/drug effects , Erythrocyte Membrane/metabolism , Phlorhizin/pharmacology , Protective Agents/pharmacology , Cell Death/drug effects , Erythrocytes/cytology , Erythrocytes/drug effects , Erythrocytes/metabolism , Humans , Oxidative Stress/drug effects
11.
J Virol ; 81(7): 3608-17, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17229685

ABSTRACT

Efficient assembly of hepatitis delta virus (HDV) was achieved by cotransfection of Huh7 cells with two plasmids: one to provide expression of the large, middle, and small envelope proteins of hepatitis B virus (HBV), the natural helper of HDV, and another to initiate replication of the HDV RNA genome. HDV released into the media was assayed for HDV RNA and HBV envelope proteins and characterized by rate-zonal sedimentation, immunoaffinity purification, electron microscopy, and the ability to infect primary human hepatocytes. Among the novel findings were that (i) immunostaining for delta antigen 6 days after infection with 300 genome equivalents (GE) per cell showed only 1% of cells as infected, but this was increased to 16% when 5% polyethylene glycol was present during infection; (ii) uninfected cells did not differ from infected cells in terms of albumin accumulation or the presence of E-cadherin at cell junctions; and (iii) sensitive quantitative real-time PCR assays detected HDV replication even when the multiplicity of infection was 0.2 GE/cell. In the future, this HDV assembly and infection system can be further developed to better understand the mechanisms shared by HBV and HDV for attachment and entry into host cells.


Subject(s)
Hepatitis Delta Virus/physiology , Hepatocytes/metabolism , Hepatocytes/virology , Virion/metabolism , Virus Assembly , Antigens, Viral/immunology , Antigens, Viral/metabolism , Cells, Cultured , Chromatography, Affinity , Hepatitis Delta Virus/ultrastructure , Humans , Microscopy, Electron, Transmission , Microscopy, Immunoelectron , RNA, Viral/metabolism , Time Factors , Viral Envelope Proteins/immunology , Viral Envelope Proteins/metabolism , Virion/immunology , Virus Assembly/immunology , Virus Replication
12.
J Virol ; 81(8): 4343-7, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17251287

ABSTRACT

Previous studies have attempted to clarify the roles of the pre-S1 and pre-S2 domains of the large envelope protein of hepatitis B virus (HBV) in attachment and entry into susceptible cells. Difficulties arise in that these domains contain regions involved in the nucleocapsid assembly of HBV and overlapping with the coding regions of the viral polymerase and RNA sequences required for reverse transcription. Such difficulties can be circumvented with hepatitis delta virus (HDV), which needs the HBV large envelope protein only for infectivity. Thus, mutated HBV envelope proteins were examined for their effects on HDV infectivity. Changing the C-terminal region of pre-S1 critical for HBV assembly allowed the envelopment of HDV and had no effect on infectivity in primary human hepatocytes. Similarly, a deletion of the 12 amino acids of a putative translocation motif (TLM) in pre-S2 had no effect. Thus, these two regions are not necessary for HDV infectivity and, by inference, are not needed for HBV attachment and entry into susceptible cells.


Subject(s)
Hepatitis B virus/genetics , Hepatitis B virus/physiology , Hepatitis Delta Virus/physiology , Mutation , Viral Envelope Proteins/physiology , Cells, Cultured , Hepatitis Delta Virus/genetics , Hepatocytes/virology , Humans , Viral Envelope Proteins/chemistry , Viral Envelope Proteins/genetics , Virus Attachment , Virus Internalization
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