Activation of progelatinase B by membranes of human polymorphonuclear granulocytes

Isolated human granulocyte plasma membranes contain progelatinase B. The binding of progelatinase B to the membrane, however, is relatively weak, and a considerable part of progelatinase B can be removed by simply washing the membrane with buffer. This detachment does not depend on the ionic strength of the buffer, indicating that electrostatic forces do not play an important role in the binding of progelatinase B to the membrane. A complete removal of progelatinase B is achieved by chromatography of neutrophil membranes on gelatin-agarose. The plasma membrane of human granulocytes activates added progelatinase B. This activation is inhibited by soybean trypsin inhibitor and is thus performed by membrane bound serine proteinases. In contrast to other reports that claimed an important role of elastase in activating progelatinase B, we found that this activation is mostly inhibited by chymostatin and not by elastatinal and is thus primarily due to cathepsin G. Proteinase 3 was shown to activate progelatinase B as efficient as neutrophil elastase, i. e. much weaker than cathepsin G. Binding of cathepsin G and elastase to the neutrophil membrane does not change their ability to activate progelatinase B. However, cathepsin G, the most potent activator of the three neutrophil serine proteinases, is only a weak activator, when compared to stromelysin-1. This, as well as only a weak binding of progelatinase B, make it doubtful that activation of membrane-bound progelatinase B by membrane-bound serine proteinases is of significant physiological importance.     

A major difference between the divergence patterns within the lines-1 families in mice and voles

L1 retroposons are represented in mice by subfamilies of interspersed sequences of varied abundance. Previous analyses have indicated that subfamilies are generated by duplicative transposition of a small number of members of the L1 family, the progeny of which then become a major component of the murine L1 population, and are not due to any active processes generating homology within preexisting groups of elements in a particular species. In mice, more than a third of the L1 elements belong to a clade that became active approximately 5 Mya and whose elements are > or = 95% identical. We have collected sequence information from 13 L1 elements isolated from two species of voles (Rodentia: Microtinae: Microtus and Arvicola) and have found that divergence within the vole L1 population is quite different from that in mice, in that there is no abundant subfamily of homologous elements. Individual L1 elements from voles are very divergent from one another and belong to a clade that began a period of elevated duplicative transposition approximately 13 Mya. Sequence analyses of portions of these divergent L1 elements (approximately 250 bp each) gave no evidence for concerted evolution having acted on the vole L1 elements since the split of the two vole lineages approximately 3.5 Mya; that is, the observed interspecific divergence (6.7%-24.7%) is not larger than the intraspecific divergence (7.9%-27.2%), and phylogenetic analyses showed no clustering into Arvicola and Microtus clades.      

Binpairs: Utilization of Illumina Paired-End Information for Improving Efficiency of Taxonomic Binning of Metagenomic Sequences

Motivation

Paired-end sequencing protocols, offered by next generation sequencing (NGS) platforms like Illumia, generate a pair of reads for every DNA fragment in a sample. Although this protocol has been utilized for several metagenomics studies, most taxonomic binning approaches classify each of the reads (forming a pair), independently. The present work explores some simple but effective strategies of utilizing pairing-information of Illumina short reads for improving the accuracy of taxonomic binning of metagenomic datasets. The strategies proposed can be used in conjunction with all genres of existing binning methods.

Results

Validation results suggest that employment of these “Binpairs” strategies can provide significant improvements in the binning outcome. The quality of the taxonomic assignments thus obtained are often comparable to those that can only be achieved with relatively longer reads obtained using other NGS platforms (such as Roche).

Availability

An implementation of the proposed strategies of utilizing pairing information is freely available for academic users at https://metagenomics.atc.tcs.com/binning/binpairs.     

Plasma progesterone concentrations in the mid-luteal phase are dependent on luteal size, but independent of luteal blood flow and gene expression in lactating dairy cows

The objective of the present study was to investigate if plasma progesterone (pP(4)) concentrations are dependent on luteal size, blood flow, or gene expression in luteal tissue. To induce cycles with high and low pP(4) concentrations, respectively, 20 lactating dairy cows received either a single treatment with 25 mg prostaglandin F(2α) (PGF(2α)) on Day 4 Hour 12 (PG1; n=8), or two treatments (25 mg PGF(2α) each) on Day 4 Hours 0 and 12 (PG2; n=12) of the estrous cycle (Day 1, Hour 0=ovulation). In four cows, ovulation occurred between 4 and 6d after the second PGF(2α) treatment; these cows and one lame cow were excluded from the study. In the 15 remaining cows with physiological interovulatory intervals, pP(4), area (LTA) and volume (LTV) of luteal tissue, as well as absolute (LBF) and relative (rLBF) luteal blood flow were determined on Day 9, and relative luteal P(4) (rLP(4)) as well as luteal mRNA expression of important receptors, angiogenic, vasoactive, and steroidogenic factors were quantified on Day 11 (±1) during two successive estrous cycles. Furthermore, rLP(4) was multiplied by LTV to produce a semiquantitative assessment of absolute luteal P(4) (LP(4)). There was no effect (P>0.05) of treatment (one or two PGF(2α) treatments), neither on pP(4) concentrations nor on any other parameter in the present study. Nevertheless, there was a lower LP(4) (P=0.01), LTA (P=0.03), and LTV (P=0.02), as well as tendencies of lower pP(4) (P=0.06) and LBF (P=0.09) at first compared with second diestrus. Plasma P(4) was related with LP(4) (r=0.43, P=0.04), LTA (r=0.65, P=0.0001), and LTV (r=0.43, P=0.02), but not with rLBF (r=-0.18, P=0.34). Furthermore, there was no significant correlation between gene expression of important steroidogenic factors and P(4) concentrations in luteal tissue. Results indicate that plasma P(4) concentrations in the mid-luteal phase were dependent on luteal size, but independent of blood flow and gene expression per luteal tissue unit.     

Communicable diseases prioritized for surveillance and epidemiological research: results of a standardized prioritization procedure in Germany, 2011

Introduction

To establish strategic priorities for the German national public health institute (RKI) and guide the institute''s mid-term strategic decisions, we prioritized infectious pathogens in accordance with their importance for national surveillance and epidemiological research.

Methods

We used the Delphi process with internal (RKI) and external experts and a metric-consensus approach to score pathogens according to ten three-tiered criteria. Additional experts were invited to weight each criterion, leading to the calculation of a median weight by which each score was multiplied. We ranked the pathogens according to the total weighted score and divided them into four priority groups.

Results

127 pathogens were scored. Eighty-six experts participated in the weighting; “Case fatality rate” was rated as the most important criterion. Twenty-six pathogens were ranked in the highest priority group; among those were pathogens with internationally recognised importance (e.g., Human Immunodeficiency Virus, Mycobacterium tuberculosis, Influenza virus, Hepatitis C virus, Neisseria meningitides), pathogens frequently causing large outbreaks (e.g., Campylobacter spp.), and nosocomial pathogens associated with antimicrobial resistance. Other pathogens in the highest priority group included Helicobacter pylori, Respiratory Syncytial Virus, Varicella zoster virus and Hantavirus.

Discussion

While several pathogens from the highest priority group already have a high profile in national and international health policy documents, high scores for other pathogens (e.g., Helicobacter pylori, Respiratory syncytial virus or Hantavirus) indicate a possible under-recognised importance within the current German public health framework. A process to strengthen respective surveillance systems and research has been started. The prioritization methodology has worked well; its modular structure makes it potentially useful for other settings.     

The Cytoprotective Effects of E-α-(4-Methoxyphenyl)-2’,3,4,4'-Tetramethoxychalcone (E-α-p-OMe-C6H4-TMC)—A Novel and Non-Cytotoxic HO-1 Inducer

Cell protection against different noxious stimuli like oxidative stress or chemical toxins plays a central role in the treatment of many diseases. The inducible heme oxygenase isoform, heme oxygenase-1 (HO-1), is known to protect cells against a variety of harmful conditions including apoptosis. Because a number of medium strong electrophiles from a series of α-X-substituted 2’,3,4,4’-tetramethoxychalcones (α-X-TMCs, X = H, F, Cl, Br, I, CN, Me, p-NO₂-C₆H₄, Ph, p-OMe-C₆H₄, NO₂, CF₃, COOEt, COOH) had proven to activate Nrf2 resulting in HO-1 induction and inhibit NF-κB downstream target genes, their protective effect against staurosporine induced apoptosis and reactive oxygen species (ROS) production was investigated. RAW264.7 macrophages treated with 19 different chalcones (15 α-X-TMCs, chalcone, 2’-hydroxychalcone, calythropsin and 2’-hydroxy-3,4,4’-trimethoxychalcone) prior to staurosporine treatment were analyzed for apoptosis and ROS production, as well as HO-1 protein expression and enzyme activity. Additionally, Nrf2 and NF-κB activity was assessed. We found that amongst all tested chalcones only E-α-(4-methoxyphenyl)-2’,3,4,4''-tetramethoxychalcone (E-α-p-OMe-C₆H₄-TMC) demonstrated a distinct, statistically significant antiapoptotic effect in a dose dependent manner, showing no toxic effects, while its double bond isomer Z-α-p-OMe-C₆H₄-TMC displayed no significant activity. Also, E-α-p-OMe-C₆H₄-TMC induced HO-1 protein expression and increased HO-1 activity, whilst inhibition of HO-1 by SnPP-IX abolished its antiapoptotic effect. The only weakly electrophilic chalcone E-α-p-OMe-C₆H₄-TMC reduced the staurosporine triggered formation of ROS, while inducing the translocation of Nrf2 into the nucleus. Furthermore, staurosporine induced NF-κB activity was attenuated following E-α-p-OMe-C₆H₄-TMC treatment. Overall, E-α-p-OMe-C₆H₄-TMC demonstrated its effective cytoprotective potential via a non-toxic induction of HO-1 in RAW264.7 macrophages. The observed cytoprotective effect may partly be related to both, the activation of the Nrf2- and inhibition of the NF-κB pathway.     

Cell surface hydrophobicity of Candida albicans isolated from elder patients undergoing denture‐related candidosis

Background: The virulence potential of Candida albicans strains enrolled in denture‐related candidosis still remains uncertain. Candida albicans cells with higher cell surface hydrophobicity (CSH) rates, so‐called hydrophobic, present higher adhesion success in different host tissues than cells with lower rates, or even hydrophilic. Objective: The proposition of this study was to evaluate the differences in the CSH of strains isolated from denture users with and without denture‐related candidosis. Material and methods: The strains were obtained from two paired groups of patients living a same retirement house. Fungal cells were submitted to CSH evaluation by the hydrocarbon partition test using xylene. Results: The measures revealed that the yeasts from patients with candidosis had CSH values ranging from 4.52% to 12.24%, with an average of 8.22 ± 2.92%. In the countergroup, the CSH ranged from 3.86% to 14.36%, with an average of 8.38 ± 3.76%. The difference between the groups were considered not relevant (p = 0.997). Conclusion: The results let to the inference that natural populations of C. albicans from patients with and without clinical manifestation denture‐related candidosis do not differ one from the other regarding to CSH.