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Stroke is a leading cause of death, with a continuously increasing incidence. As a metabolic process that catabolizes glucose pyruvate and provides adenosine triphosphate (ATP), glycolysis plays a crucial role in different diseases. Phosphoglycerate kinase 1 (PGK1) facilitates energy production with biosynthesis in many diseases, including stroke. However, the exact role of PGK1/glycolysis in stroke remains to be elucidated. A rat model of middle cerebral artery occlusion (MCAO) was used to mimic ischemia/reperfusion injuries. Oxygen glucose deprivation/re-oxygenation (OGD/R) was used to induce injury to highly aggressively proliferating immortalized (HAPI) rat microglial cells. The extracellular acidification rate (ECAR) was determined using an XFe24 Extracellular Flux Analyzer. ATP, lactate dehydrogenase, tumor necrosis factor-alpha, and interleukin-6 levels were measured using commercial kits. Chromatin immunoprecipitation assay was performed to examine the interaction between H3K27ac or p300 and the PGK1 promoter region. PGK1 was either knocked down or overexpressed by lentivirus. Thus, to examine its role in stroke, real-time polymerase chain reaction and immunoblotting were used to measure gene expression. The expression of PGK1 was increased and associated with M1 polarization and glycolysis in MCAO rat models. OGD/R promoted M1 polarization and HAPI microglial cell inflammation by regulating glycolysis. Silencing PGK1 reduced OGD/R-increased M1 polarization, inflammation, and glycolysis. Conversely, the overexpression of PGK1 promoted HAPI microglial cell inflammation by regulating glycolysis. The mechanism showed that histone acetyltransferase p300 promoted PGK1 expression through H3K27 acetylation. Finally, data indicated that silencing PGK1 inhibited microglia M1 polarization, inflammation, and glycolysis in MCAO rat models. PGK1 could promote ischemia/reperfusion injury-induced microglial M1 polarization and inflammation by regulating glycolysis, which might provide a novel direction in developing new therapeutic medications for preventing or treating stroke.

Note: Please see pdf for full abstract with equations. This paper considers a model for oncolytic virotherapy given by a thiply haptotactic cross-diffusion system ut = DuΔu − ξu∇ · (u∇v) + μuu(1 − u) − ρuuz, x ∈ Ω, t > 0, vt = −(αuu + αww)v + μvv(1 − v), x ∈ Ω, t > 0, wt = DwΔw − ξw∇ · (w∇v) − δww + ρwuz, x ∈ Ω, t > 0, zt = DzΔz − ξz∇ · (z∇v) − δzz − ρzuz + βw, x ∈ Ω, t > 0, (Du∇u − ξuu∇v) · ν = (Dw∇w − ξww∇v) · ν = (Dz∇z − ξzz∇v) · ν = 0, x ∈ ∂Ω, t > 0, u(x, 0) = u0(x), v(x, 0) = v0(x), w(x, 0) = w0(x), z(x, 0) = z0(x), x ∈ Ω, (0.1) in a bounded domain Ω ⊂ RN (N = 1, 2) with smooth boundary. We prove that when N = 1, the system possesses a unique global bounded solution. When N = 2, if there exists some constant K > 0 such that Dz > ξzK, then the solution is global in time. And if we add the condition δwρz > ρwβ > 0, the solution is globally bounded. Furthermore, with some suitable assumption, we could also obtain that the solution exponentially stabilizes to the constant equilibrium (1,0,0,0) as t → ∞.

In this paper, we consider a three-dimensional chemotaxis-Stokes system 0.1 $$\begin{aligned} \left\{ \begin{aligned}&n_t+u\cdot \nabla n=\Delta n^m-\nabla \cdot (nS(x,n,c)\cdot \nabla c),&\quad&x\in \Omega , t>0,\\&c_t+u\cdot \nabla c=\Delta c-nf(c),&\quad&x\in \Omega ,t>0,\\&u_t+\nabla P=\Delta u+n\nabla \phi ,&\quad&x\in \Omega ,t>0,\\&\nabla \cdot u=0,&\quad&x\in \Omega ,t>0,\\&(\nabla n^m- n S(x,n,c)\cdot \nabla c)\cdot \nu =\frac{\partial c}{\partial \nu }=0,u=0,&\quad&x\in \partial \Omega ,t>0,\\&n(x,0)=n_0(x),c(x,0)=c_0(x),u(x,0)=u_0(x),&\quad&x\in \Omega \end{aligned} \right. \end{aligned}$$ in a bounded domain $$\Omega \subset {\mathbb {R}}^3$$ with smooth boundary, where $$\phi $$ , f and S are given functions with values in $$\Omega $$ , $$[0,\infty )$$ and $${\mathbb {R}}^{3\times 3}$$ , respectively, under the no-flux boundary condition for n, c and Dirichlet boundary condition for u. It is also required that $$f\in C^1([0,\infty ))$$ is locally bounded in $$[0,\infty )$$ , that S satisfies $$|S(x,n,c)|\le n^{l-2}S_0(c)$$ with some nondecreasing $$S_0:[0,\infty )\rightarrow [0,\infty )$$ , and that m fulfills 0.2 $$\begin{aligned} m>\frac{5}{3}l-\frac{20}{9}\quad \text {and}\quad m>-\frac{3}{4}l+\frac{21}{8}\quad \text {with}\quad \frac{25}{12}\ge l>2. \end{aligned}$$ Then, with any reasonably regular initial data, the corresponding initial-boundary problem for (0.1) processes a global in time and bounded solution. This result extends the previous global boundedness result with $$m>m_*(l)$$ , where $$\begin{aligned} m_*(l)=\left\{ \begin{aligned}&l-\frac{5}{6},&\quad&\text {if }\,\frac{31}{12}\ge l>2,\\&\frac{7}{5}l-\frac{28}{15},&\quad&\text {if }\,l>\frac{31}{12}, \end{aligned} \right. \end{aligned}$$ ([15]) since both $$\begin{aligned} l-\frac{5}{6}\ge \frac{5}{3}l-\frac{20}{9} \end{aligned}$$ and $$\begin{aligned} l-\frac{5}{6}\ge -\frac{3}{4}l+\frac{21}{8} \end{aligned}$$ hold on $$\frac{25}{12}\ge l>2$$ .

This work considers a pursuit-evasion model\begin{document}$\begin{equation} \left\{ \begin{split} &u_t = \Delta u-\chi\nabla\cdot(u\nabla w)+u(\mu-u+av),\\ &v_t = \Delta v+\xi\nabla\cdot(v\nabla z)+v(\lambda-v-bu),\\ &w_t = \Delta w-w+v,\\ &z_t = \Delta z-z+u\\ \end{split} \right. \ \ \ \ \ (1) \end{equation}$\end{document}with positive parameters \begin{document}$ \chi $\end{document}, \begin{document}$ \xi $\end{document}, \begin{document}$ \mu $\end{document}, \begin{document}$ \lambda $\end{document}, \begin{document}$ a $\end{document} and \begin{document}$ b $\end{document} in a bounded domain \begin{document}$ \Omega\subset\mathbb{R}^N $\end{document} (\begin{document}$ N $\end{document} is the dimension of the space) with smooth boundary. We prove that if \begin{document}$ a and \begin{document}$ \frac{N(2-a)}{2(C_{\frac{N}{2}+1})^{\frac{1}{\frac{N}{2}+1}}(N-2)_+}>\max\{\chi,\xi\} $\end{document}, (1) possesses a global bounded classical solution with a positive constant \begin{document}$ C_{\frac{N}{2}+1} $\end{document} corresponding to the maximal Sobolev regularity. Moreover, it is shown that if \begin{document}$ b\mu, the solution (\begin{document}$ u,v,w,z $\end{document}) converges to a spatially homogeneous coexistence state with respect to the norm in \begin{document}$ L^\infty(\Omega) $\end{document} in the large time limit under some exact smallness conditions on \begin{document}$ \chi $\end{document} and \begin{document}$ \xi $\end{document}. If \begin{document}$ b\mu>\lambda $\end{document}, the solution converges to (\begin{document}$ \mu,0,0,\mu $\end{document}) with respect to the norm in \begin{document}$ L^\infty(\Omega) $\end{document} as \begin{document}$ t\rightarrow \infty $\end{document} under some smallness assumption on \begin{document}$ \chi $\end{document} with arbitrary \begin{document}$ \xi $\end{document}.

A simple and rapid preconcentration technique, based on collecting trace nitrite on a membrane filter and dissolving the membrane filter in an organic solvent, has been applied to its spectrophotometric determination in water. At pH 2.0, nitrous acid diazotizes with p -aminoacetophenone. which is then coupled with N -(1-naphthyl)ethylenediamine, at the same pH. The azo dye formed is collected on a 0.45 urn nitrocellulose filter at pH 4.7 as its ion associate with dodecyl sulfate. The ion associate and filter are dissolved in a small volume of 2-methoxyethanol (methylcellosolve), and acidized with 0.05 ml of 2 M hydrochloric acid and the absorbance of the resulting solution is measured at 555 nm against a reagent blank. Detection limits better than O.1 μ g/dm −3 as NO 2 − can be achieved. The ions normally present in water do not interfere when sodium metaphosphate is added as a masking agent. The proposed method has been applied to the analysis of water samples from several sources, the recoveries of the nitrite added to the samples are quantitative, and results found are satisfactory.

L'identification des anions mineraux ou organiques est permise grâce a la connection en serie d'une valve trois voies et d'un detecteur de conductivite a courant continu apres le detecteur a impulsion d'un chromatographe ionique avec suppresseur d'eluant. Presentation et discussion des courbes de chronoamperometrie de divers ions (acetate, hexanesulfonate, phosphate, IO 3 − , ClO 4 − , SO 4 2− , S 2 O 6 2− )

Conception et utilisation d'un detecteur pour la chromatographie ionique, constitue d'une cellule de mesure comprenant deux electrodes et fonctionnant sous flux