Value of MRI T2 FLAIR Vascular Hyperintensities Combined with DWI ASPECTS in Predicting the Prognosis of Acute Cerebral Infarction with Endovascular Treatment.

OBJECTIVE: To explore the MRI T2 fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH) combined with diffusion-weighted imaging (DWI) Alberta Stroke Program Early CT Score (ASPECTS) in predicting the prognosis of acute cerebral infarction (ACI) with endovascular treatment. METHODS: The patients with ACI in the anterior circulation who underwent endovascular treatment from June 2016 to December 2020 were divided into a good prognosis group and a poor prognosis group according to the modified Rankin Scale (mRS) score at 90 days after the operation. The differences in general clinical baseline data, CT-ASPECTS, FVH, and DWI-ASPECTS between the two groups were analyzed. The receiver operating characteristic (ROC) curve was used to analyze the predictive power of prediction models on prognosis. RESULTS: The results of the Binomial Logistic regression equation showed initial National Institute of Health stroke scale (NIHSS), Mori grade, DWI-ASPECTS, and FVH were independent risk factors for prognosis. The predictive power of the FVH + DWI-ASPECTS prediction model was highest, and the predictive power of DWI-ASPECTS was higher than that of CT-ASPECTS. CONCLUSION: DWI-ASPECTS is better than CT-ASPECTS in predicting the prognosis of ACI with endovascular treatment, and the combined prediction model of FVH and DWI-ASPECTS has higher prediction performance, which can be used as a preoperative evaluation method to predict the effect of endovascular treatment for ACI.

Expression of microRNA­222 in serum of patients with Alzheimer's disease.

The aim of the present study was to determine the association between Alzheimer's disease (AD) and microRNA­222 in the serum of patients with AD. The expression of microRNAs was detected and the results were verified using microarray analysis and reverse transcription­quantitative polymerase chain reaction. The results indicated that there were 35 strips of microRNA in the mild AD group, in which the difference of expression signal was >500 IU/ml. There were 26 strips of microRNA with a difference in expression signal of >500 IU/ml in the mild and moderate AD groups. The downregulation of microRNA­222 in the mild and moderate groups was statistically significant (P<0.01), and the expression of microRNA­222 in the moderate group was significantly lower, compared with that in the mild AD group (P<0.05). It was concluded that microRNA­222 may affect the occurrence and development of AD through a variety of mechanisms, and may serve as a biomarker for the early diagnosis of AD.

[Efficiency and mechanism on reduction of U(VI) by sulfate reducing bacteria].

Under anaerobic conditions, the characteristics of sulfate reducing bacteria (SRB) were applied to reduce U(VI) under different temperature, pH values, U(VI) concentrations and coexisting ions. The results showed that the optimum reduction condition was the temperature 35 degrees C, pH 7.0 and U(VI) concentration 25 mg x L(-1). The maximum reduction capacity of SRB was 179.1 mg x g(-1). Mo(VI) or Ca2+ did not affect SRB on the reduction process of U(VI) under the concentration less than 5 g x L(-1), but they strongly inhibited the process under the concentration more than 20 g x L(-1). The main inhibition of Mo (VI) was physiological inhibition and the inhibition of Ca2+ was competitive inhibition through the stable complex formation, Ca-UO2-CO3. The results also showed that lag phase did not appear on the concentration of Ca2+ less than 5 g x L(-1), but the lag phase of 24 hours appeared on the concentration of Ca2+ more than 20 g x L(-1).

Protein kinase-X interacts with Pin-1 and Polycystin-1 during mouse kidney development.

The regulation of epithelial branching morphogenesis by bone morphogenetic protein-7 depends, in part, on functionally defined cyclic adenosine monophosphate (cAMP)-dependent protein kinases. We previously identified protein kinase-X (PRKX), a cAMP-dependent kinase, as a regulator of epithelial morphogenesis during kidney development and found that it binds to and phosphorylates Polycystin-1. Overexpression of PRKX stimulates renal epithelial cell migration, tubulogenesis, ureteric bud branching, and glomerular induction in embryonic mouse kidney explants in organ cultures. Here we determined the physiological functions of endogenous PRKX. Knockdown by siRNA of PRKX gene expression in a human fetal collecting tubule (HFCT) cell line exceeded 70% and resulted in decreased cell migration and increased adhesion of the cells to a collagen I matrix. In embryonic mouse kidney explants, the same degree of knockdown decreased ureteric bud branching and glomerular induction. Because PRKX BAG-3 PIN-1 and MAGI-1 are all expressed in ureteric bud derivatives, we tested for interactions among them and found that PRKX binds to all three proteins through its WW domain as determined by TransSignal domain arrays, and it coimmunoprecipitated with Pin-1 in HFCT cell lysates. These studies suggest that Polycystin-1 and Pin-1 may mediate the function of PRKX in kidney development.

Transduction of pancreatic islets with pseudotyped adeno-associated virus: effect of viral capsid and genome conversion.

BACKGROUND: Recombinant adeno-associated viral (rAAV) vectors currently show promise for islet gene therapy. In the presence of complementing AAV2 Rep proteins, AAV2 genomes can be packaged with other serotype capsids to assemble infectious virions. During transduction, the ssDNA to dsDNA conversion is one of the major rate-limiting steps that contribute to the slow onset of transgene expression. METHODS: Using pseudotyping strategy, we produced double-stranded (dsAAV) and single-stranded (ssAAV) rAAV2 genomes carrying the GFP reporter gene packaged into AAV1, AAV2, and AAV5 capsids. The ability of cross-packaged AAV1, AAV2, and AAV5 at the same genome containing particle (gcp) concentration to transduce murine and human pancreatic islets was evaluated by GFP positive cell percentage. Transgenic expression was also determined by transplant transduced human islet into SCID mice. RESULTS: Pseudotyped rAAV2/1 based vectors transduced murine islets at greater efficiency than either rAAV2/2 or rAAV2/5 vectors. For human islets transduction, the rAAV2/2 vector was more efficient than rAAV2/1 or rAAV2/5 vectors. rAAV2/2 transduced human islets more efficiently than murine islets, while rAAV2/1 transducted murine islets more efficiently than human islets. dsAAV, which do not require second strand synthesis and thus are potentially more efficient, evidenced 5 fold higher transduction ability than ssAAV vectors. Pseudotyped rAAV transduced islet grafts maintained normal function, expressed transgenic product persistently in vivo, and reversed diabetes. CONCLUSIONS: The transduction efficiency of rAAV vectors was dependent on the cross-packaged capsid. The vector capsids permit species-specific transduction. For human islets, dsAAV2/2 vectors may be the most efficient vector for clinical development.

TGF-beta induces Foxp3 + T-regulatory cells from CD4 + CD25 - precursors.

CD4 + CD25 + regulatory T cells (Tregs) are potent suppressors, playing important roles in autoimmunity and transplantation tolerance. Understanding the signals necessary for the generation and expansion of Tregs is important for clinical cellular therapy, but only limited progress has been made. Recent reports suggest a role for TGF-beta in the generation of Tregs from CD4 + CD25 - precursors, but the mechanism remains unknown. Here, we demonstrate that TGF-beta2 triggers Foxp3 expression in CD4 + CD25 - precursors, and these Foxp3 + cells act like conventional Tregs. The generation of Foxp3 + Tregs requires stimulation of the T-cell receptor, the IL-2R and the TGF-beta receptor. More importantly, strong costimulation through CD28 prevents Foxp3 expression and suppressive function in an IL-4-dependent manner. Furthermore, TGF-beta-driven Tregs inhibit innate inflammatory responses to syngeneic transplanted pancreatic islets and enhance islet transplant survival. Thus, TGF-beta is a key regulator of the signaling pathways that initiate and maintain Foxp3 expression and suppressive function in CD4 + CD25 - precursors. TGF-beta and signaling through TGF-beta receptor, CD28 costimulation and IL-4 may be key components for the manipulation of Treg. The de novo generation of Foxp3 + cells from CD4 + cells has the potential to be used for treatment of autoimmune diseases and induction of transplant tolerance.

Elevated vascular endothelial growth factor production in islets improves islet graft vascularization.

Successful islet transplantation depends on the infusion of sufficiently large quantities of islets, of which only approximately 30% become stably engrafted. Rapid and adequate revascularization of transplanted islets is important for islet survival and function. Delayed and insufficient revascularization can deprive islets of oxygen and nutrients, resulting in islet cell death and early graft failure. To improve islet revascularization, we delivered human vascular endothelial growth factor (VEGF) cDNA to murine islets, followed by transplantation under the renal capsule in diabetic mice. Diabetic animals receiving a marginal mass of 300 islets that were pretransduced with a VEGF vector exhibited near normoglycemia. In contrast, diabetic mice receiving an equivalent number of islets that were transduced with a control vector remained hyperglycemic. Immunohistochemistry with anti-insulin and anti-CD31 antibodies revealed a relatively higher insulin content and greater degree of microvasculature in the VEGF vector-transduced islet grafts, which correlated with significantly improved blood glucose profiles and enhanced insulin secretion in response to glucose challenge in this group of diabetic recipient mice. These results demonstrate that VEGF production in islets stimulates graft angiogenesis and enhances islet revascularization. This mechanism might be explored as a novel strategy to accelerate islet revascularization and improve long-term survival of functional islet mass posttransplantation.

Viral IL-10 gene transfer inhibits the expression of multiple chemokine and chemokine receptor genes induced by inflammatory or adaptive immune stimuli.

Previously we have shown that adenovirus-mediated gene transfer and expression of vIL-10 are able to prolong cardiac allograft survival, through the inhibition of the immune response to both alloantigen and adenoviral antigens. In the current study, we have defined further mechanisms of Ad.vIL-10-mediated prolongation of cardiac allograft survival. E1- and E3-deleted adenoviral vectors encoding beta-galactosidase or vIL-10 were transferred into grafts at the time of transplantation, chemokine and chemokine receptor expression were evaluated by a pathway-specific cDNA array, and the results were confirmed with real time RT-PCR on selected genes. Ischemic injury, alloantigen and adenovirus vector induced the expression of multiple pro-inflammatory chemokines in the grafts, which likely amplify allograft rejection. Most of these Th1-related chemokine genes were inhibited or down-regulated by Ad.vIL-10 administration, which may help to decrease leukocytic infiltration and improve graft survival. Among the potent Th1 type chemokines inhibited were the CXCR3 ligands CXCL9 and CXCL10, which could directly inhibit vector-mediated gene expression in myoblasts, although targeting CXCR3 or its ligands did not prolong allograft survival with vIL-10 gene transfer. Ad.vIL-10 administration also induced the expression of the Th2-associated chemokines eotaxin-2 and MIP-1 gamma, suggesting Th1 to Th2 immune deviation. These results demonstrated that the vIL-10 gene transfer inhibits chemokine expression, preventing stimulation of innate and adaptive immunity.

Differential chemokine and chemokine receptor gene induction by ischemia, alloantigen, and gene transfer in cardiac grafts.

Transplantation of allogeneic grafts presents several challenges to the innate and adaptive immune systems including chemokine leukocyte recruitment, activation, and effector function. We defined the chemokines and receptors induced by the transplant procedure/ischemia injury, alloantigen and gene transfer vector administration in murine cardiac grafts. E1, E3 deleted AdRSVbetagal was transferred into grafts at the time of transplantation, grafts were harvested after 1-14 days, and a pathway-specific cDNA array was used to evaluate the levels of 67 chemokine and chemokine receptor genes. Transplantation resulted in ischemic injury and induction of a number of similar genes in both the syngeneic and allogeneic grafts, such as CXCL1 and CXCL5, which increased dramatically on day 1 and returned rapidly to baseline in the syngeneic grafts. Alloantigen stimulated the adaptive immune response and induced the presence of more inflammatory genes within the grafts, particularly at later time points. The adenovirus vector induced a broader panel of genes, among them potent inflammatory chemokines CXCL9 and CXCL10, that are induced earlier or more strongly compared with alloantigen stimulation alone. As alloantigen and adenovirus vectors both induce similar sets of genes, targeting these molecules may not only inhibit alloimmunity, but also enhance the utility of the gene transfer vector.

Adenovirus transduction induces expression of multiple chemokines and chemokine receptors in murine beta cells and pancreatic islets.

Adenoviral vectors are highly efficient for transferring genes to islets. However, the inflammatory and immune responses stimulated by adenovirus may be detrimental to islet survival. Given the role of chemokines and their receptors in inflammation, we analyzed their expression in isolated murine islets, in a murine beta cell line and in syngeneic islet grafts after adenovirus transduction (AdRSVLacZ). AdRSVLacZ transduction enhanced and induced the expression of a variety of chemokines. Transduced syngeneic transplanted islets showed significantly enhanced expression of multiple chemokines and receptors, including monocyte chemoattractant protein-1 (MCP-1), CC chemokine receptor 2 (CCR2) and regulated upon activation, normal T cell expressed and secreted (RANTES), compared with untransduced islet grafts. AdRSVLacZ-transduced islet grafts had significant mononuclear infiltrates, and in situ hybridization demonstrated intragraft expression of MCP-1, CCR2 and RANTES. Although adenovirus transduction did not impair in vitro insulin secretion, diabetes was reversed in only one of six recipients of a marginal mass of AdRSVLacZ-transduced islets, compared with six of six control recipients. In conclusion, multiple chemokines and chemokine receptors are expressed by murine islets constitutively and in response to adenovirus transduction. Adenovirus transduction impairs engraftment of marginal mass of transplanted islets. This is not because of direct vector toxicity of islet secretory capacity, but may be related to host innate immunity in response to adenovirus vector.