A Quasi-Solid-Phase Approach to Activate Natural Minerals for Zeolite Synthesis

Synthesis of zeolites or zeolite/clay composites from natural aluminosilicate minerals has received extensive attention because of its great usefulness in greening the zeolite manufacturing process, in which effective activation of natural aluminosilicate minerals is crucially important. Herein, we present an energy saving and green approach, the quasi-solid-phase activation method, to efficiently destruct the natural minerals under the conditions of a temperature as low as 100 °C and an activation time as short as 30 min. Our strategy consists of the following three steps: (1) preparation of a mixture of a natural kaolin mineral, NaOH, and water by kneading, (2) extruding of the mixture into sticks, and (3) low-temperature calcination of the stick, featured by the combined use of mechanochemical actions. The results showed that 84.7% Si species and 69.0% Al species in the kaolin mineral underwent a large degree of depolymerization in the kneading and extruding steps, and following calcination at 100 °C resulted in the complete depolymerization of the kaolin mineral to monomer orthosilicate anions (Q⁰) and tetracoordinated aluminum (Al^IV) species, which are highly active silica and alumina sources for synthesizing aluminosilicate zeolites. Using the activated kaolin mineral as a starting material, pure-phase NaY and NaA zeolites have been successfully synthesized

Lipopolysaccharide Induces Immune Activation and SIV Replication in Rhesus Macaques of Chinese Origin

<div><p>Background</p><p>Chronic immune activation is a hallmark of progressive HIV infection and a key determinant of immunodeficiency in HIV-infected individuals. Bacterial lipopolysaccharide (LPS) in the circulation has been implicated as a key factor in HIV infection-related systemic immune activation. We thus investigate the impact of LPS on systemic immune activation in simian immunodeficiency virus (SIV)-infected rhesus macaques of Chinese origin.</p><p>Methods</p><p>The animals were inoculated intravenously with SIVmac239. The levels of plasma viral load and host inflammatory cytokines in PBMC were measured by real-time RT-PCR. CD4/CD8 ratio and systemic immune activation markers were examined by flow cytometric analysis of PBMCs. White blood cell and neutrophil counts and C Reactive Protein levels were determined using biochemistry analyzer. The plasma levels of LPS were determined by Tachypleus Amebocyte Lysate (TAL) test.</p><p>Results</p><p>The animals inoculated with SIVmac239 became infected as evidenced by the increased plasma levels of SIV RNA and decreased CD4/CD8 ratio. LPS administration of SIV-infected animals induced a transient increase of plasma SIV RNA and immune activation, which was indicated by the elevated expression of the inflammatory cytokines and CD4+HLA-DR+ T cells in PBMCs.</p><p>Conclusions</p><p>These data support the concept that LPS is a driving factor in systemic immune activation of HIV disease.</p></div

SIV infection of Chinese rhesus monkeys.

<p>Six animals were intravenously inoculated with SIVmac239 (10³ TCID50). Blood samples were collected from the animals at the indicated time points postinfection. A: Plasma levels of SIV GAG gene RNA were measured by real-time PCR. B: CD4/CD8 ratios were measured by flow cytometry. C: Average SIV loads and CD4/CD8 ratios (mean ± SEM) of SIV-infected animals.</p

Effect of LPS on SIV replication.

<p>SIV-infected animals were intravenously injected with either a single dose of LPS (50 µg/kg; solid circles and lines, n = 3) or saline (open circle and dashed lines, n = 3) at 45 weeks postinfection. The plasma samples were collected at the indicated time points after LPS treatment. A: The plasma levels of LPS were determined by Tachypleus Amebocyte Lysate (TAL) test. B: SIV loads were measured by real-time PCR for SIV GAG gene expression.</p

Effect of LPS on inflammatory cytokines in PBMCs.

<p>SIVmac239-infected animals were intravenously injected with a single dose of LPS (50 µg/kg, solid circles and lines, n = 3) or saline (open circle and dashed lines, n = 3) at 45 weeks postinfection. Blood samples were collected at indicated time points post-LPS administration and PBMCs were isolated. The levels of cytokines (IL-6, IL-8, IFN-α, and TNF-α) in PBMCs were determined by real-time PCR and normalized to GAPDH mRNA. Data are expressed as fold of control (before LPS administration, cytokine mRNA/GAPDH mRNA, which was defined as 1).</p

Animals Used for the Study.

<p>*I.V. = intravenous;</p><p>**analyzed at day 315 (45 weeks) post SIV inoculation.</p

Effect of LPS on WBC, neutrophils and CRP.

<p>SIVmac239-infected animals were intravenously injected with either LPS (50 µg/kg; solid circles and lines, n = 3) or saline (open circle and dashed lines, n = 3) at 45 weeks postinfection. At the indicated time points after LPS administration, white blood cell (WBC) counts (A), neutrophil counts (B), and C Reactive Protein (CRP) levels (C) were determined by a biochemistry analyzer.</p

Effect of LPS on CD4/CD8 ratio, counts of CD4+ T cells and frequency of CD4+HLA-DR+ T cells.

<p>SIVmac239-infected animals were intravenously injected with either LPS (50 µg/kg; solid circles and lines, n = 3) or saline (open circle and dashed lines, n = 3) at 45 weeks postinfection. At the indicated time points after LPS administration, the CD4/CD8 ratios (A), total CD4+ T cell counts (B), and CD4+HLA-DR+ T cell percentage in PBMCs (C) were determined by flow cytometry.</p

Primer Pairs for Real-Time RT-PCR.

<p>Primer Pairs for Real-Time RT-PCR.</p