Glioma-derived S100A9 polarizes M2 microglia to inhibit CD8+T lymphocytes for immunosuppression via αvß3 integrin/AKT1/TGFß1.

Our previous studies showed that S100A9 was overexpressed in glioma and promoted tumor growth. However, S100A9 can also be secreted by tumor cells to regulate the tumor microenvironment (TME). In this study, we aimed to explore the functions of glioma derived-S100A9 in microglial M2 polarization, resulting in inhibition of CD8+ T lymphocytes and promotion of immunosuppression. We first showed that glioma exhibited higher expression and secretion of S100A9 than astrocytes. After knocking down S100A9 in two glioma cell lines, the secretion of S100A9 was repressed. Then, the medium was collected and considered as conditioned medium (CM), which was incubated with microglia. We found that glioma-derived S100A9 drove microglial M2 polarization and increased TGFß1 secretion. These molecular mechanisms were related to the interaction of S100A9 with αvß3 integrin and the subsequent activation of AKT1 in microglia. Furthermore, we demonstrated that S100A9-induced M2 microglia negatively affected cell viability, IL-2 and IFN-γ secretion, together with increased early apoptosis in CD8+T lymphocytes via TGFß1. Additionally, glioma cells were implanted into mouse brains, and we confirmed that S100A9 stimulated microglial M2 polarization, enhanced TGFß1 levels and repressed CD8+ T lymphocytes in orthotopically transplanted tumors. In human glioma samples, S100A9 expression was positively associated with CD206 expression, but negatively correlated with CD8+T lymphocyte accumulation in the TME. Our data indicated that glioma-derived S100A9 has a promising ability to manipulate non-malignant cells and promote immune evasion in the TME, providing valuable insight into the mechanism by which S100A9 participates in the progression of glioma.

A method to alleviate false-positive results of the Elecsys HIV combi PT assay.

To explore the effects of urea dissociation on reducing false-positive results of  the Elecsys HIV combi PT assay. A retrospective analysis was used to evaluate the false-positive rate of the Elecsys HIV combi PT assay. Six false-positive sera, six positive sera and six sera from patients with early HIV infection were collected. Dissociation was performed using 1 mol/L, 2 mol/L, 4 mol/L, 6 mol/L, or 8 mol/L urea, and HIV screening assay were then detected to select the appropriate concentration of urea dissociation. Next, 55 false-positive sera and 15 sera from early HIV infection were used to verify the best concentration of urea to achieve dissociation. Retrospective analysis showed that the COI of the Elecsys HIV combi PT assay in false-positive sera ranged from 1.0 to 200.0, and approximately 97.01%(227/234) of false-positive sera were in the range of 1.0-15.0. The avidity index (AI) in positive and false-positive sera decreased as the urea dissociation concentration increased. When the dissociation concentration was 6 mol/L, the AI of false-positive serum was between 0.0234 and 0.2567, and the AI of early HIV infection sera was between 0.4325 and 0.5017. The difference in AI between false-positive and positive samples was significant. When negativity was defined as an AI of less than 0.3970, the sensitivity and specificity were 100.0% and 100.0%, respectively. Urea-mediated dissociation could significantly reduce the false-positive rate of the Elecsys HIV combi PT assay with a low COI. Our findings provided a reference for distinguishing positive and false-positive of the Elecsys HIV combi PT assay.

Accurately Predicting the Radiation Enhancement Factor in Plasmonic Optical Antenna Emitters.

Plasmonic optical antennas (POAs), often constructed from gold or silver nanostructures, can enhance the radiation efficiency of emitters coupled to POAs and are applied in surface-enhanced Raman spectroscopy (SERS) and light-emitting devices. Over the past four decades, radiation enhancement factors (REFs) of POA-emitter systems were considered to be difficult to calculate directly and have been predicted indirectly and approximately, assuming POAs are illuminated by electromagnetic plane waves without emitters. The validity of this approximation remains a significant open problem in SERS theory. Herein, we develop a method based on the rigorous optical reciprocity theorem for accurately calculating the REFs of emitters in nanoparticle-substrate nanogaps for single-molecule SERS and scanning probe-substrate nanogaps for tip-enhanced Raman spectroscopy. We show that the validity of the plane wave approximation breaks down if high-order plasmonic modes are excited. The as-developed method paves the way toward designing high-REF POA nanostructures for luminescence-related devices.

Costs, Trends, and Related Factors in Treating Lung Cancer Patients in 67 Hospitals in Guangxi, China.

Lung cancer is a common disease with high mortality in China. Recent economic advances have led to improved medical capabilities, while costs associated with treating this disease have increased. Such change contributes to a commonly held belief that healthcare costs are out of control. However, few studies have examined this issue. Here, we use 34,678 hospitalization summary reports from 67 Guangxi hospitals (period 2013-2016) to document costs, temporal trends, and associated factors. Findings from this study are surprising in that they debunk the myth of uncontrolled healthcare costs. In addition, results and experiences from Guangxi are informative for other comparable regions.

Assessment of potential factors associating with costs of hospitalizing cardiovascular diseases in 141 hospitals in Guangxi, China.

BACKGROUND: The rising cost of healthcare is of great concern in China, as evidenced by the media features negative reports almost daily. However there are only a few studies from well-developed cities, like Beijing or Shanghai, and little is known about healthcare costs in rest of the country. In this study, we use hospitalization summary reports (HSRs) from admitted cardiovascular diseases patients in Guangxi hospitals during 2013-2016, and we investigate temporal trends of healthcare costs and associated factors. METHODS: By generalized additive model, we compute temporal trends of cost per stay (CPS), cost per day (CPD) and others. We then use generalized linear models to assess which factors associate with CPS and CPD. FINDINGS: Using a total of 760,000 HSRs, we find that CPS appears to be stabilized around $1040 until the middle of year 2015, before exhibiting a downward trend. Similarly, CPD exhibits similar stable pattern. Meanwhile, surgery-specific CPS showed an increase in year 2013-2014, and then stabilized. Drug costs account for over 1/3 of CPS, but they are gradually declining. Costs associated with physicians' and nurses' services represent less than 5% of CPS. We found that age, sex, marital status, occupation and payment methods are significantly associated with CPS or CPD. Interestingly, we found no association between patient ethnicity and these costs. However, we did find that minority patients use more secondary hospitals than Han patients. INTERPRETATIONS: Healthcare costs in Guangxi are stable, contrary to the rise portrayed by Chinese mass media. Several factors can be associated with healthcare costs, and these may be useful for developing evidence-based policies. In particular, there is a need to encourage more Han patients to seek care in primary and secondary hospitals.

Xenobiotic metabolism of plant secondary compounds in the English grain aphid, Sitobion avenae (F.) (Hemiptera: Aphididae).

Plant secondary compounds have been documented to be deleterious to insects and other herbivores in diverse ways. In this study, the effect of catechol (phenolics), gramine (alkaloid) and L-ornithine-HCI (non-protein amino acid) on the activities of xenobiotic metabolizing enzymes in English grain aphid, Sitobion avenae, was evaluated. Phase I enzymes investigated in this study included carboxylesterase (CarE), and oxidoreductase, whereas Phase II enzymes were represented by glutathione S-transferase (GST). In general, CarE and GST activities in S. avenae were positively correlated with the concentration of plant secondary compounds in artificial diets. Oxidoreductase activity, however, displayed a different profile. Specifically, peroxidase (POD) and polyphenol oxidase (PPO) activities in S. avenae were positively correlated with concentrations of dietary catechol and gramine, respectively, whereas catalase (CAT) activity was significantly suppressed by the higher concentration of catechol, gramine and L-ornithine-HCl. These combined results suggest that CarE and GST in S. avenae are key enzymes to breakdown a broad spectrum of plant secondary compounds, whereas oxidoreductase, including PPO and POD, degrades specific groups of plant secondary compounds.

[Chemical composition of volatile oil from Chromolaena odorata and its effect on plant, fungi and insect growth].

The volatile oil from C. odorata had a significant effect on the growth of plants, fungi and insects. The result showed that the seedling growth of five test plants was obviously inhibited, in the order of ryegrass > Chinese cabbage > radish > snap been > rice. The inhibitory effect of the oil at its middle concentration (800 mg.L-1) for Pyricularia grisea was the strongest, the next was to Phytophthora nicotianae, and the weakest was to Fusarium axysporum. The inhibitory percentage was 61.40%, 29.27% and 14.44%, respectively. The volatile oil from C. odorata at the dose of 10-20 microliters.plant-1 had a significant oviposition deterrent effect on Phyllotreta striolata and Plutella xylostella. The volatile oil from C. odorata was analyzed by GC/MS and thirty components were identified. Terpenoids compounds were major components of the volatile oil, such as trans-caryophyllene (16.58%), delta-cadinene (15.85%), alpha-copaene (11.58%), caryophyllene oxide (9.63%), germacrene-D (4.96%), and delta-humulene (4.32%).

[Chemical components of volatile oil from Mikania micrantha and its biological activity on insects].

The chemical components of volatile oil from Mikania micrantha were analyzed by GC/MS. Twenty-two compounds were identified, and monoterpenes and sesquiterpenes as well as alcohol and ketone with their derivatives were major components. Biological activity of volatile oil on insect was investigated. The results showed that the volatile oil had significant deterrent effect on oviposition of Plutella xylostella, Phyllotreta striolata and Phaedon brassicae at dose of 5-10 microliters.plant-1. They also possessed established contracting toxicity, and their rectifying reduce rates for Lipaphis erysimi were 50.0%, 59.86%, 62.51% at concentration of 500, 750, and 1000 mg.L-1, respectively. However, they had not fumigating toxicity for virginogeniae, L. erysimi, 2nd instar larvae of P. xylostella, and adult of P. striolata at concentration of 500 mg.L-1.

[Allelopathic potential of volatile oil from Mikania micrantha].

Mikania micrantha, an exotic plant species, is an important weed in south China. The volatile oil of the weed species had significant biological activities on plants and their pathogens, particularly Pyricularia grisea. The results showed that the seeding growth of 6 plant species decreased obviously when exposed to increasing concentration (200, 400, 800, 1600 mg.L-1) of the volatile oil. The fresh weight of all test plants decreased, and the emergence of all test plants delayed for 1-2 days under soil treatment (2500 g.hm-2). The inhibitory effect of volatile oil of M. micrantha at its medium concentration was the most strong on Pyricularia grisea; secondary on Fusarium oxysporum; but weak on Phytophthora nicotianae. The inhibitory rate was 53.38%, 28.66% and 18.69% for the three plant pathogens, respectively.