[Multidrug-resistant organisms (MDRO) in patients in outpatient care in the Rhine-Main region, Germany, in 2014: Prevalence and risk factors]. / Multiresistente Erreger bei Patienten ambulanter Pflegedienste im Rhein-Main-Gebiet 2014 : Prävalenz und Risikofaktoren.

BACKGROUND: Data on the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in outpatient care are scarce and those on the prevalence of multidrug-resistant Gram-negative bacteria (MRGN) are lacking completely. Therefore, the network on multidrug-resistant organisms (MDRO) in the Rhine-Main region (MRE-Netz Rhein-Main) performed a multicenter study on current prevalence data and risk factors for MDRO. MATERIALS AND METHODS: Characteristics of all patients were obtained according to a modified healthcare-associated infections in long-term care facilities (HALT) questionnaire and swabs from the nares/throat and anus were tested for MRSA and extended-spectrum beta-lactamase (ESBL)/MRGN. Risk factors were calculated via odds ratios. RESULTS: Ten nursing services with 486 patients participated in this study, 269 patients agreed to having swabs of the nares/throat taken, and 132 patients had anal swabs. MRSA was detected in 3.7%, and ESBL/MRGN in 14.4% of the patients (6.8% ESBL, 7.6% MRGN, 0% MRGN). Risk factors for MRSA were high dependency on care (stage 3 or above; OR 5.1), antibiotic use during the preceding 3 months (O R 3.7), hospital stay during the last 6 months (OR 4.3), and a positive history for MRSA (OR 18.1). Incontinence and preceding hospital stays proved to be risk factors for ESBL colonization (OR 9.5 or 6.5), whereas risk factors for MRGN colonization were a high level of care dependency (OR 7.5), urinary catheter (OR 8.3), percutaneous endoscopic gastrostomy tube and other stomata (OR 6.2), and artificial respiration (OR 5), in addition to a positive history for MRSA (OR 20) and ESBL (OR 6.7). CONCLUSION: Considering the high prevalence of colonization with MDRO in outpatient care, nursing services must be competent in caring for such patients: good hygiene procedures, including hand hygiene and appropriate handling in wound management, punctures and injections, with catheters, stomata, and if necessary with artificial respiration should be practiced. The guidelines of the German Commission on hospital hygiene and infection prevention should also be observed.

Reconciling an archaeal origin of eukaryotes with engulfment: a biologically plausible update of the Eocyte hypothesis.

An archaeal origin of eukaryotes is often equated with the engulfment of the bacterial ancestor of mitochondria by an archaeon. Such an event is problematic in that it is not supported by archaeal cell biology. We show that placing phylogenetic results within a stem-and-crown framework eliminates such incompatibilities, and that an archaeal origin for eukaryotes (as suggested from recent phylogenies) can be uncontroversially reconciled with phagocytosis as the mechanism for engulfment of the mitochondrial ancestor. This is significant because it eliminates a perceived problem with eukaryote origins: that an archaeal origin of eukaryotes (as under the Eocyte hypothesis) cannot be reconciled with existing cell biological mechanisms through which bacteria may take up residence inside eukaryote cells.

Comparative genomic evidence for a complete nuclear pore complex in the last eukaryotic common ancestor.

BACKGROUND: The Nuclear Pore Complex (NPC) facilitates molecular trafficking between nucleus and cytoplasm and is an integral feature of the eukaryote cell. It exhibits eight-fold rotational symmetry and is comprised of approximately 30 nucleoporins (Nups) in different stoichiometries. Nups are broadly conserved between yeast, vertebrates and plants, but few have been identified among other major eukaryotic groups. METHODOLOGY/PRINCIPAL FINDINGS: We screened for Nups across 60 eukaryote genomes and report that 19 Nups (spanning all major protein subcomplexes) are found in all eukaryote supergroups represented in our study (Opisthokonts, Amoebozoa, Viridiplantae, Chromalveolates and Excavates). Based on parsimony, between 23 and 26 of 31 Nups can be placed in LECA. Notably, they include central components of the anchoring system (Ndc1 and Gp210) indicating that the anchoring system did not evolve by convergence, as has previously been suggested. These results significantly extend earlier results and, importantly, unambiguously place a fully-fledged NPC in LECA. We also test the proposal that transmembrane Pom proteins in vertebrates and yeasts may account for their variant forms of mitosis (open mitoses in vertebrates, closed among yeasts). The distribution of homologues of vertebrate Pom121 and yeast Pom152 is not consistent with this suggestion, but the distribution of fungal Pom34 fits a scenario wherein it was integral to the evolution of closed mitosis in ascomycetes. We also report an updated screen for vesicle coating complexes, which share a common evolutionary origin with Nups, and can be traced back to LECA. Surprisingly, we find only three supergroup-level differences (one gain and two losses) between the constituents of COPI, COPII and Clathrin complexes. CONCLUSIONS/SIGNIFICANCE: Our results indicate that all major protein subcomplexes in the Nuclear Pore Complex are traceable to the Last Eukaryotic Common Ancestor (LECA). In contrast to previous screens, we demonstrate that our conclusions hold regardless of the position of the root of the eukaryote tree.

Progestogens cause immunosuppression of stimulated carp (Cyprinus carpio L.) leukocytes in vitro.

The involvement of steroid hormones in direct and indirect regulation and modulation of immune responses is well recognized in mammals. Here, we demonstrate that progestogens are capable of influencing the innate immunity in fish as well. Therefore, we confirmed the known immunosuppressive effects of natural progesterone (P4), and compared them to influences of 17alpha,20beta-dihydroxy progesterone (DHP4) and the synthetic progestins, medroxyprogesterone acetate (MPA) and levonorgestrel (LEV), on NO release by in vitro-stimulated carp leukocytes derived from both, head and trunk kidney, respectively. DHP4 known as the main maturation-inducing steroid in many teleosts potently inhibited the NO release by carp leukocytes. The synthetic progestin MPA, which may also be environmentally relevant due to its world-wide use in hormonal contraception, significantly decreased NO formation by head and trunk kidney cells. In contrast, LEV showed no significant influence on NO release by head and trunk kidney leukocytes. The observed immunosuppressive actions of progestogens on NO production were compared to the known impairment by natural and synthetic glucocorticoids. Determining the potential impact of progestogens on mRNA expression of iNOS by means of semi-quantitative reverse transcription polymerase chain reactions (RT-PCR) revealed downregulation of proinflammatory type I immune response characteristics at high concentrations. These findings demonstrate for the first time that similar to the known effects of natural progesterone synthetic progestogens are also able to influence immune signaling cascades in fish, and provide evidence that these steroids are capable of influencing mRNA expression of iNOS. The induction of a regulatory type II immune response by progestogens is a striking example of interference of female steroid-mediated events with the piscine immune system. Furthermore, the identification of a partial sequence of a membrane-associated progestogen receptor (mPR) in carp leukocytes by RT-PCR indicates a specific mechanism underlying the observed effects of progestogens on these immune cells.

Endocrine disruption in aquatic vertebrates.

Environmental compounds can interfere with endocrine systems of wildlife and humans. The main sink of such substances, called endocrine disrupters (ED), are surface waters. Thus, aquatic vertebrates, such as fish and amphibians, are most endangered. ED can adversely affect reproductive biology and the thyroid system. ED act by (anti)estrogenic and (anti)androgenic modes of action, resulting in abnormal sexual differentiation and impaired reproduction. These effects are mainly driven by direct interferences of ED with sex steroid receptors rather than indirectly by impacting synthesis and bioavailability of sex steroids, which in turn might affect the hypothalamic-pituitary-gonadal axis. Recent findings reveal that, in addition to the human-produced waste of ED, natural sources, such as parasites and decomposition of leaves, also might act as ED, markedly affecting sexual differentiation and reproduction in fish and amphibians. Although the thyroid system has essential functions in both fish and amphibians, amphibian metamorphosis has been introduced as the most sensitive model to detect thyroidal ED; no suitable fish model exists. Whereas ED may act primarily on only one specific endocrine target, all endocrine systems will eventually be deregulated as they are intimately connected to each other. The recent ecotoxicological issue of pharmaceutically active compounds (PhACs) present in the aquatic environment indicates a high potential for further endocrine modes of action on aquatic vertebrates by ED derived from PhACs, such as glucocorticoids, progestins, and beta-agonists.

Production of nitric oxide by carp (Cyprinus carpio L.) kidney leukocytes is regulated by cyclic 3',5'-adenosine monophosphate.

The inducible nitric oxide synthase (iNOS) plays a central role in the inflammatory reactions that follow infection or tissue damage. Induction of nitric oxide (NO) synthesis by bacterial lipopolysaccharide (LPS) depends on activation of G protein-coupled receptors in mammals. Thus, it was our intention to evaluate whether similar mechanisms are involved in iNOS activation in fish leukocytes. Therefore, the participation of membrane-bound receptors which activate effectors via G proteins has been confirmed using the G protein inhibitor suramin. Furthermore, the NO produced by iNOS performs both beneficial and detrimental actions. It is thus conceivable that regulatory mechanisms exist which control the timing and intensity of NO production by iNOS in order to outweigh protective effects against detrimental ones. The second messenger cAMP produced by adenylyl cyclases (ACs) plays a key role in the regulation of many cellular functions. Since cAMP signaling inhibits numerous immunological reactions, studies have been carried out to determine whether cAMP-dependent pathways could inhibit NO production by carp leukocytes as well. To measure cellular responses such as NO production by carp leukocytes derived from head and trunk kidneys treatments were performed with the cAMP elevating agents forskolin and dibutyryl-cAMP (db-cAMP) prior to stimulation with Aeromonas hydrophila. Pharmacological studies in stimulated kidney leukocytes showed that increased intracellular cAMP levels lead to reduced NO formation. This reduction of NO production was not due to decreased cell numbers, since a tetrazolium dye-based assay revealed no reduction of cell viability by cyclic nucleotide elevating agents. Thus, our data provide evidence that the AC/cAMP signaling pathway is well established in carp leukocytes. Cyclic AMP leads to type II immune response. We provide evidence that the predominant AC in fish leukocytes is a particulate enzyme due to its sensitivity to forskolin. Treatment of leukocytes with agents increasing intracellular cAMP gave clear evidence for participation of this cyclic nucleotide in immune signaling.

Outsourcing the nucleus: nuclear pore complex genes are no longer encoded in nucleomorph genomes.

The nuclear pore complex (NPC) facilitates transport between nucleus and cytoplasm. The protein constituents of the NPC, termed nucleoporins (Nups), are conserved across a wide diversity of eukaryotes. In apparent exception to this, no nucleoporin genes have been identified in nucleomorph genomes. Nucleomorphs, nuclear remnants of once free-living eukaryotes, took up residence as secondary endosymbionts in cryptomonad and chlorarachniophyte algae. As these genomes are highly reduced, Nup genes may have been lost, or relocated to the host nucleus. However, Nup genes are often poorly conserved between species, so absence may be an artifact of low sequence similarity. We therefore constructed an evolutionary bioinformatic screen to establish whether the apparent absence of Nup genes in nucleomorph genomes is due to genuine absence or the inability of current methods to detect homologues. We searched green plant (Arabidopsis and rice), green alga (Chlamydomonas reinhardtii) and red alga (Cyanidioschyzon merolae) genomes, plus two nucleomorph genomes (Bigelowiella natans and Guillardia theta) with profile hidden Markov models (HMMs) from curated alignments of known vertebrate/yeast Nups. Since the plant, algal and nucleomorph genomes all belong to the kingdom Plantae, and are evolutionarily distant from the outgroup (vertebrate/yeast) training set, we use the plant and algal genomes as internal positive controls for the sensitivity of the searches in nucleomorph genomes. We find numerous Nup homologues in all plant and free-living algal species, but none in either nucleomorph genome. BLAST searches using identified plant and algal Nups also failed to detect nucleomorph homologues. We conclude that nucleomorph Nup genes have either been lost, being replaced by host Nup genes, or, that nucleomorph Nup genes have been transferred to the host nucleus twice independently; once in the evolution of the red algal nucleomorph and once in the green algal nucleomorph.