Effects of a Randomized Intervention to Improve Workplace Social Capital in Community Health Centers in China

Objective

To examine whether workplace social capital improved after implementing a workplace social capital intervention in community health centers in China.

Methods

This study was conducted in 20 community health centers of similar size in Jinan of China during 2012–2013. Using the stratified site randomization, 10 centers were randomized into the intervention group; one center was excluded due to leadership change in final analyses. The baseline survey including 447 staff (response rate: 93.1%) was conducted in 2012, and followed by a six-month workplace social capital intervention, including team building courses for directors of community health centers, voluntarily public services, group psychological consultation, and outdoor training. The follow-up survey in July 2013 was responded to by 390 staff members (response rate: 86.9%). Workplace social capital was assessed with the translated and culturally adapted scale, divided into vertical and horizontal dimensions. The facility-level intervention effects were based on all baseline (n = 427) and follow-up (n = 377) respondents, except for Weibei respondents. We conducted a bivariate Difference-in-Difference analysis to estimate the facility-level intervention effects.

Results

No statistically significant intervention effects were observed at the center level; the intervention increased the facility-level workplace social capital, and its horizontal and vertical dimensions by 1.0 (p = 0.24), 0.4 (p = 0.46) and 0.8 (p = 0.16), respectively.

Conclusions

The comprehensive intervention seemed to slightly improve workplace social capital in community health centers of urban China at the center level. High attrition rate limits any causal interpretation of the results. Further studies are warranted to test these findings.     

Kinetic analysis using low-molecular mass xyloglucan oligosaccharides defines the catalytic mechanism of a Populus xyloglucan endotransglycosylase

Plant XETs [XG (xyloglucan) endotransglycosylases] catalyse the transglycosylation from a XG donor to a XG or low-molecular-mass XG fragment as the acceptor, and are thought to be important enzymes in the formation and remodelling of the cellulose-XG three-dimensional network in the primary plant cell wall. Current methods to assay XET activity use the XG polysaccharide as the donor substrate, and present limitations for kinetic and mechanistic studies of XET action due to the polymeric and polydisperse nature of the substrate. A novel activity assay based on HPCE (high performance capillary electrophoresis), in conjunction with a defined low-molecular-mass XGO {XG oligosaccharide; (XXXGXXXG, where G=Glcbeta1,4- and X=[Xylalpha1,6]Glcbeta1,4-)} as the glycosyl donor and a heptasaccharide derivatized with ANTS [8-aminonaphthalene-1,3,6-trisulphonic acid; (XXXG-ANTS)] as the acceptor substrate was developed and validated. The recombinant enzyme PttXET16A from Populus tremula x tremuloides (hybrid aspen) was characterized using the donor/acceptor pair indicated above, for which preparative scale syntheses have been optimized. The low-molecular-mass donor underwent a single transglycosylation reaction to the acceptor substrate under initial-rate conditions, with a pH optimum at 5.0 and maximal activity between 30 and 40 degrees C. Kinetic data are best explained by a ping-pong bi-bi mechanism with substrate inhibition by both donor and acceptor. This is the first assay for XETs using a donor substrate other than polymeric XG, enabling quantitative kinetic analysis of different XGO donors for specificity, and subsite mapping studies of XET enzymes.     

Comparison of PDQuest and Progenesis software packages in the analysis of two-dimensional electrophoresis gels

Efficient analysis of protein expression by using two-dimensional electrophoresis (2-DE) data relies on the use of automated image processing techniques. The overall success of this research depends critically on the accuracy and the reliability of the analysis software. In addition, the software has a profound effect on the interpretation of the results obtained, and the amount of user intervention demanded during the analysis. The choice of analysis software that best meets specific needs is therefore of interest to the research laboratory. In this paper we compare two advanced analysis software packages, PDQuest and Progenesis. Their evaluation is based on quantitative tests at three different levels of standard 2-DE analysis: spot detection, gel matching and spot quantitation. As test materials we use three gel sets previously used in a similar comparison of Z3 and Melanie, and three sets of gels from our own research. It was observed that the quality of the test gels critically influences the spot detection and gel matching results. Both packages were sensitive to the parameter or filter settings with respect to the tendency of finding true positive and false positive spots. Quantitation results were very accurate for both analysis software packages.     

Monosodium Urate Activates Src/Pyk2/PI3 Kinase and Cathepsin Dependent Unconventional Protein Secretion From Human Primary Macrophages

Monosodium urate (MSU) is an endogenous danger signal that is crystallized from uric acid released from injured cells. MSU is known to activate inflammatory response in macrophages but the molecular mechanisms involved have remained uncharacterized. Activated macrophages start to secrete proteins to activate immune response and to recruit other immune cells to the site of infection and/or tissue damage. Secretome characterization after activation of innate immune system is essential to unravel the details of early phases of defense responses. Here, we have analyzed the secretome of human primary macrophages stimulated with MSU using quantitative two-dimensional gel electrophoresis based proteomics as well as high-throughput qualitative GeLC-MS/MS approach combining protein separation by SDS-PAGE and protein identification by liquid chromatography-MS/MS. Both methods showed that MSU stimulation induced robust protein secretion from lipopolysaccharide-primed human macrophages. Bioinformatic analysis of the secretome data showed that MSU stimulation strongly activates unconventional, vesicle mediated protein secretion. The unconventionally secreted proteins included pro-inflammatory cytokines like IL-1β and IL-18, interferon-induced proteins, and danger signal proteins. Also active forms of lysosomal proteases cathepsins were secreted on MSU stimulation, and cathepsin activity was essential for MSU-induced unconventional protein secretion. Additionally, proteins associated to phosphorylation events including Src family tyrosine kinases were increased in the secretome of MSU-stimulated cells. Our functional studies demonstrated that Src, Pyk2, and PI3 kinases act upstream of cathepsins to activate the overall protein secretion from macrophages. In conclusion, we provide the first comprehensive characterization of protein secretion pathways activated by MSU in human macrophages, and reveal a novel role for cathepsins and Src, Pyk2, PI3 kinases in the activation of unconventional protein secretion.The innate immune system is activated in response to microbial infection and tissue damage. Macrophages are the central players of the innate immunity and detect the presence of pathogen-associated molecular patterns (PAMPs)¹ and damage-associated molecular patterns (DAMPs) with their pattern recognition receptors. This recognition results in the activation of antimicrobial defense, inflammatory response, tissue regeneration, and recruitment of other inflammatory cells to the site of infection and/or tissue damage (1). Proper innate immune response is essential for the activation of the adaptive immune system. At present it is thought that the activation of innate immunity is most effective when both signals of microbial origin and damage are perceived at the same time (2, 3).Monosodium urate (MSU) is an endogenous DAMP that is crystallized from uric acid released by injured cells (4). Uric acid is a byproduct of purine degradation, and abnormally high levels of uric acid in serum, or hyperuricemia, is a hallmark of metabolic disorders where balance between intake of purines via food and excretion of uric acid is distorted. A well-known disease associated to hyperuricemia is gouty arthritis, in which deposits of MSU can be found in synovial fluid of peripheral joints, and MSU-induced inflammation is the initial trigger of symptoms (5). Hyperuricemia is also linked to other inflammatory diseases, like metabolic syndrome (6, 7), type 2 diabetes (8), and cardiovascular disease (9). MSU-induced inflammation is driven by the innate immune system. MSU engages antigen-presenting cells, macrophages, and dendritic cells. It is a potent adjuvant, initiating a robust adaptive immune response (4). Recently it has been shown that the adjuvant properties of alum are dependent on release of uric acid in vivo (10).It is unclear how cells detect the presence of MSU. It has been suggested that MSU activates intracellular signaling pathways in dendritic cells by directly engaging cellular membranes, particularly the cholesterol-rich components of the plasma membrane (11). Recently Uratsuji and coworkers showed that MSU activates inflammatory response in keratinocytes and monocytic THP-1 cells through membrane-associated P2Y6 (12). It is also well-documented that MSU activates the NLRP3 inflammasome in macrophages (13). The NLRP3 inflammasome is a multiprotein complex comprising of NACHT, LRR, and PYD domains-containing protein 3 (NLRP3), Apoptosis-associated speck-like protein containing a CARD (ASC) and cysteine protease Caspase-1. Activation of NLRP3 inflammasome results in the autocleavage of Caspase-1. The activated Caspase-1 then in turn cleaves pro-inflammatory cytokines IL-1β and IL-18 into their biologically active forms, which are then readily secreted (14–17). However, the signaling pathways that are involved in MSU-induced NLRP3 inflammasome activation have remained only partially characterized.Macrophages respond to activating stimuli by producing inflammatory mediators that are delivered to neighboring cells through multiple protein secretion pathways including both conventional and unconventional protein secretion (18). Conventionally secreted proteins contain an N-terminal signal peptide, which directs their transport to the plasma membrane through the well-characterized endoplasmic reticulum (ER)-Golgi pathway. In contrast, mediators and regulators of unconventional protein secretion pathways are less well understood. At present, different proteomic techniques allow for in-depth analysis of the secretome, the global pattern of secreted proteins. Secretome analysis is important in revealing complex cellular processes that require communication and signaling between the cells, and it has recently been applied to analyze the signaling pathways related to cell differentiation (19, 20), cancer (21, 22), and immune responses (23–25). In the present work we have characterized the secretome of human primary macrophages that have been activated simultaneously by microbial signal lipopolysaccharide (LPS) and endogenous danger signal MSU to get a global view of macrophage response to combined PAMP and DAMP stimulation.     

Salmonella in animal slurry can be destroyed by aeration at low temperatures

Cattle and other animals infected by Salmonella can emit high numbers of these bacteria. To determine an effective means for reducing this bacterial group in animal slurry, samples were subjected to aeration in laboratory experiments and in farm-scale slurry tanks. A clear reduction in Salmonella levels was found in laboratory experiments at temperatures from 4 to 40 °C. Aeration in farm-scale slurry tanks increased the temperature above the ambient temperatures (often less than 0 °C) to maxima ranging between 19 and 40 °C. Farm-scale aeration resulted in similar reductions in Salmonella as those achieved in laboratory experiments. Thus, reductions, ranging from greater than 99% of the initial number to no detectable Salmonella , could be reached after 2–5 weeks using aeration processes with cattle slurries contaminated by Salm. infantis or pig slurry contaminated by Salm. typhimurium . These results suggest that farmers can control the spread of Salmonella from slurry to agricultural fields. The reduction mechanisms remain unknown, though the increase in pH (to 7·6–9·0) found in slurries after aeration might exert a decreasing effect on these bacteria.     

Double antibody solid-phase radioimmunoassay for staphylococcal enterotoxin A

Summary A double antibody solid-phase (DASP) radioimmunoassay for staphylococcal enterotoxin A is described. In the assay the antigen-antibody complex is precipitated by anti-rabbit serum which is adsorbed onto a solid carrier (cellulose). The method is sensitive to 200 pg of enterotoxin. It was possible to detect as little as 2–5 ng enterotoxin A/ml food extract from minced meat and sausage. Enterotoxins B and C were not found to inhibit the uptake of labeled enterotoxin A at a level which might distort the results of the enterotoxin A assay. The DASP technique is sensitive, rapid, and easy to perform and thus compares favorably with other radioimmunoassays for enterotoxin.