144 research outputs found
Unassisted solar lignin valorisation using a compartmented photo-electro-biochemical cell
Lignin is a major component of lignocellulosic biomass. Although it is highly recalcitrant to break down, it is a very abundant natural source of valuable aromatic carbons. Thus, the effective valorisation of lignin is crucial for realising a sustainable biorefinery chain. Here, we report a compartmented photo-electro-biochemical system for unassisted, selective, and stable lignin valorisation, in which a TiO2 photocatalyst, an atomically dispersed Co-based electrocatalyst, and a biocatalyst (lignin peroxidase isozyme H8, horseradish peroxidase) are integrated, such that each system is separated using Nafion and cellulose membranes. This cell design enables lignin valorisation upon irradiation with sunlight without the need for any additional bias or sacrificial agent and allows the protection of the biocatalyst from enzymedamaging elements, such as reactive radicals, gas bubbles, and light. The photo-electrobiochemical system is able to catalyse lignin depolymerisation with a 98.7% selectivity and polymerisation with a 73.3% yield using coniferyl alcohol, a lignin monomer
Reaction Chemistry and Kinetics of Corn Stalk Pyrolysis without and with Ga/HZSM-5
The bifunctional Ga/HZSM-5 catalyst has been proven having the capability to increase the selectivity of aromatics production during catalytic pyrolysis of furan and woody biomass. However, the reaction chemistry and kinetics of pyrolysis of herbaceous biomass promoted by Ga/HZSM-5 is rarely reported. Pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) analysis and non-isothermal thermogravimetric analysis at four heating rates were carried out to investigate the decomposition behavior and pyrolysis kinetics of corn stalk without and with Ga/HZSM-5. The effective activation energies for corn stalk pyrolysis were calculated by using the Friedman isoconversional method. The Py–GC/MS analysis results indicated that the Ga/HZSM-5 catalyst had a high selectivity toward producing the aromatic chemicals of xylene, toluene and benzene, whereas the major products from non-catalytic pyrolysis of corn stalk were oxygenated compounds. The presence of Ga/HZSM-5 could significantly reduce the effective activation energies of corn stalk pyrolysis from 159.9–352.4 kJ mol−1 to 41.6–99.8 kJ mol−1 in the conversion range of 0.10–0.85
The rationale of opportunistic bilateral salpingectomies (OBS) during benign gynaecological and obstetric surgery : a consensus text of the Flemish Society of Obstetrics and Gynaecology (VVOG)
Ovarian cancer (OC), is a disease difficult to diagnose in an early stage implicating a poor prognosis. The 5-year
overall survival in Belgium has not changed in the last 18 years and remains 44 %. There is no effective screening
method (secondary prevention) to detect ovarian cancer at an early stage. Primary prevention of ovarian cancer
came in the picture through the paradigm shift that the fallopian tube is often the origin of ovarian cancer and
not the ovary itself. Opportunistic bilateral salpingectomy (OBS) during benign gynaecological and obstetric
surgery might have the potential to reduce the risk of ovarian cancer by as much as 65 %. Bilateral risk-reducing
salpingectomy during a benign procedure is feasible, safe, appears to have no impact on the ovarian function and
seems to be cost effective. The key question is whether we should wait for a RCT or implement OBS directly in our
daily practice. Guidelines regarding OBS within our societies are therefore urgently needed. Our recommendation
is to inform all women without a child wish, undergoing a benign gynaecological or obstetrical surgical procedure
about the pro’s and the con’s of OBS and advise a bilateral salpingectomy. Furthermore, there is an urgent need
for a prospective registry of OBS. The present article is the consensus text of the Flemish Society of Obstetrics and
Gynaecology (VVOG) regarding OBS
Transition of tumor-associated macrophages from MHC class IIhi to MHC class IIlow mediates tumor progression in mice
<p>Abstract</p> <p>Background</p> <p>Tumor-associated macrophages (TAMs) are the most abundant immune cells within the tumor stroma and play a crucial role in tumor development. Although clinical investigations indicate that high levels of macrophage (MΦ) infiltration into tumors are associated with a poor prognosis, the exact role played by TAMs during tumor development remains unclear. The present study aimed to investigate dynamic changes in TAM major histocompatibility complex (MHC) class II expression levels and to assess the effects of these changes on tumor progression.</p> <p>Results</p> <p>Significant inhibition of tumor growth in the murine hepatocellular carcinoma Hepa1-6 model was closely associated with partial TAM depletion. Strikingly, two distinct TAM subsets were found to coexist within the tumor microenvironment during Hepa1-6 tumor development. An MHC class II<sup>hi </sup>TAM population appeared during the early phase of tumor development and was associated with tumor suppression; however, an MHC class II<sup>low </sup>TAM population became increasingly predominant as the tumor progressed.</p> <p>Conclusions</p> <p>Tumor progression was positively correlated with increasing infiltration of the tumor tissues by MHC class II<sup>low </sup>TAMs. Thus, targeting the transition of MΦ may be a novel strategy for drug development and immunotherapy.</p
B Cell: T Cell Interactions Occur within Hepatic Granulomas during Experimental Visceral Leishmaniasis
Hepatic resistance to Leishmania donovani infection in mice is associated with the development of granulomas, in which a variety of lymphoid and non-lymphoid populations accumulate. Although previous studies have identified B cells in hepatic granulomas and functional studies in B cell-deficient mice have suggested a role for B cells in the control of experimental visceral leishmaniasis, little is known about the behaviour of B cells in the granuloma microenvironment. Here, we first compared the hepatic B cell population in infected mice, where ≈60% of B cells are located within granulomas, with that of naïve mice. In infected mice, there was a small increase in mIgMlomIgD+ mature B2 cells, but no enrichment of B cells with regulatory phenotype or function compared to the naïve hepatic B cell population, as assessed by CD1d and CD5 expression and by IL-10 production. Using 2-photon microscopy to quantify the entire intra-granuloma B cell population, in conjunction with the adoptive transfer of polyclonal and HEL-specific BCR-transgenic B cells isolated from L. donovani-infected mice, we demonstrated that B cells accumulate in granulomas over time in an antigen-independent manner. Intra-vital dynamic imaging was used to demonstrate that within the polyclonal B cell population obtained from L. donovani-infected mice, the frequency of B cells that made multiple long contacts with endogenous T cells was greater than that observed using HEL-specific B cells obtained from the same inflammatory environment. These data indicate, therefore, that a subset of this polyclonal B cell population is capable of making cognate interactions with T cells within this unique environment, and provide the first insights into the dynamics of B cells within an inflammatory site
Innate Immune Responses of Pulmonary Epithelial Cells to Burkholderia pseudomallei Infection
10.1371/journal.pone.0007308PLoS ONE410
Caffeic Acid Phenethyl Ester Causes p21Cip1 Induction, Akt Signaling Reduction, and Growth Inhibition in PC-3 Human Prostate Cancer Cells
Caffeic acid phenethyl ester (CAPE) treatment suppressed proliferation, colony formation, and cell cycle progression in PC-3 human prostate cancer cells. CAPE decreased protein expression of cyclin D1, cyclin E, SKP2, c-Myc, Akt1, Akt2, Akt3, total Akt, mTOR, Bcl-2, Rb, as well as phosphorylation of Rb, ERK1/2, Akt, mTOR, GSK3α, GSK3β, PDK1; but increased protein expression of KLF6 and p21Cip1. Microarray analysis indicated that pathways involved in cellular movement, cell death, proliferation, and cell cycle were affected by CAPE. Co-treatment of CAPE with chemotherapeutic drugs vinblastine, paclitaxol, and estramustine indicated synergistic suppression effect. CAPE administration may serve as a potential adjuvant therapy for prostate cancer
Applications of lignin in the agri-food industry
Of late, valorization of agri-food industrial by-products and their sustainable utilization is
gaining much contemplation world-over. Globally, 'Zero Waste Concept' is promoted with
main emphasis laid towards generation of minimal wastes and maximal utilization of plantbased
agri-food raw materials. One of the wastes/by-products in the agri-food industry are the
lignin, which occurs as lignocellulosic biomass. This biomass is deliberated to be an
environmental pollutant as they offer resistance to natural biodegradation. Safe disposal of this
biomass is often considered a major challenge, especially in low-income countries. Hence, the
application of modern technologies to effectively reduce these types of wastes and maximize
their potential use/applications is vital in the present day scenario. Nevertheless, in some of the
high-income countries, attempts have been made to efficiently utilize lignin as a source of fuel, as a raw material in the paper industry, as a filler material in biopolymer based packaging and
for producing bioethanol. However, as of today, agri-food industrial applications remains
significantly underexplored. Chemically, lignin is heterogeneous, bio-polymeric, polyphenolic
compound, which is present naturally in plants, providing mechanical strength and rigidity.
Reports are available wherein purified lignin is established to possess therapeutic values; and
are rich in antioxidant, anti-microbial, anti-carcinogenic, antidiabetic properties, etc.
This chapter is divided into four sub-categories focusing on various technological
aspects related to isolation and characterization of lignin; established uses of lignin; proved
bioactivities and therapeutic potentials of lignin, and finally on identifying the existing research
gaps followed by future recommendations for potential use from agri-food industrial wastes.Theme of this chapter is based on our ongoing project- Valortech,
which has received funding from the European Union’s Horizon 2020 research and innovation
program under grant agreement No 810630
- …