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Drug-controlled release is recognized as effective for improving compliance with treatment and obtaining better therapeutic efficacy with less toxicity in cancer treatment. However, few reports in this area are involved in nucleic acids delivery, especially in RNA therapeutics delivery. In this study, an injectable hydrogel Methacrylated gelatin (GM) scaffold was introduced into a dual-RNA hybrid delivery complex hybrid lipid particle (HLP) to form a G-HLP/RNAs system. This system can control the release of both siRNA and mRNA and was found to be efficient for protecting these RNAs from biodegradation and retaining their therapeutic effect over 7 days. Further, a tumor environment (TME)-activation function after peritumoral injection of mocked GM scaffold was observed. Then, matured DC cells and activated T-cells were detected by the addition of HLP/RNAs complex, thus verifying the immunoactivation function of GM scaffold and its ability to reserve immune cells and antigens. Finally, two doses of G-HLP/RNAs treatment efficiently suppressed C26 tumor growth in mice with a tumor weight inhibition rate of 71.9%. Owing to its ability to achieve RNA drug-controlled release, alter TME, and induce tumor apoptosis, the G-HLP/RNAs system may become a valuable tool for cancer gene therapy.

The chimeric antigen receptor-T cells (CAR-T) therapy, as a novel personalized immunotherapy, has shown prominent clinical efficacy in the treatment of B-cell malignancies. However, the progress in solid tumors was hindered by multiple elements in the tumor immunosuppressive microenvironment. In this study, an injectable and photocurable Gelatin Methacryloyl (GelMA) hydrogel was applied to be a depot of CAR-T cells, thus forming an injectable CAR-T Gelatin Methacryloyl hydrogels Delivery (i-GMD) system. According to our results, CAR-T cells in this system could be normally amplified, sustained released, and play an anti-tumor role in vitro. When compared with local or intravenously injection of CAR-T solution, injection of i-GMD matrix around tumor demonstrated enhanced anti-tumor effect and markedly extended survival of mice. Our research outcomes indicated that this therapeutic strategy might hopefully provide a treatment for patients with unresectable tumors.

Several results based on the likelihood-ratio test have been discussed in the literature for testing the scale parameters of two exponential distributions under complete and different censored form...

Vaccines can stimulate the immune system to protect individuals from infectious diseases. Moreover, vaccines have also been applied to the prevention and treatment of cancers. Due to advances in genetic engineering technology, cancer vaccines could be genetically modified to increase antitumor efficacy. Various genes could be inserted into cells to boost the immune response, such as cytokines, T cell costimulatory molecules, tumor-associated antigens, and tumor-specific antigens. Genetically modified cancer vaccines utilize innate and adaptive immune responses to induce durable antineoplastic capacity and prevent the recurrence. This review will discuss the major approaches used to develop genetically modified cancer vaccines and explore recent advances to increase the understanding of engineered cancer vaccines.

Multiple myeloma (MM) remains an incurable hematologic malignancy, despite the development of numerous innovative therapies during the past two decades. Immunotherapies are changing the treatment paradigm of MM and have improved the overall response and survival of patients with relapsed/refractory (RR) MM. B cell maturation antigen (BCMA), selectively expressed in normal and malignant plasma cells, has been targeted by several immunotherapeutic modalities. Chimeric antigen receptor (CAR) T cells, the breakthrough in cancer immunotherapy, have revolutionized the treatment of B cell malignancies and remarkably improved the prognosis of RRMM. BCMA-targeting CAR T cell therapy is the most developed CAR T cell therapy for MM, and the US Food and Drug Administration has already approved idecabtagene vicleucel (Ide-cel) and ciltacabtagene autoleucel (Cilta-cel) for MM. However, the development of novel BCMA-targeting CAR T cell therapies remains in progress. This review focuses on BCMA-targeting CAR T cell therapy, covering all stages of investigational progress, including the innovative preclinical studies, the initial phase I clinical trials, and the more developed phase II clinical trials. It also discusses possible measures to improve the efficacy and safety of this therapy.

Chimeric antigen receptor T (CAR-T) cell therapy has demonstrated remarkable efficacies in treating hematopoietic malignancies, but not in the solid tumors. Incorporating costimulatory signaling domains, such as ICOS or 4-1BB, can positively influence CAR-T cell functions and then the immune responses. These CAR-engineered T cells have showed their enhanced persistence and effector functions with improved antitumor activities, and provided a new approach for the treatment of solid tumors. Here, we designed novel 2nd generation CARs with a costimulatory signaling molecule, dectin-1. The impacts of dectin-1 signaling domain on CAR-T cells were evaluated in vitro and in vivo. Our data show that in vitro cytokine secretions by HER2 or CD19 specific CAR-T cells increase significantly via incorporating this dectin-1 signaling domain. Additional properties of these novel CAR-T cells are affected by this costimulatory domain. Compared with a popular reference (i.e., anti-HER2 CAR-T cells with 4-1BB), in vitro T cell functions and in vivo antitumor activity of the dectin-1 engineered CAR-T cells are similar to the 4-1BB based, and both are discrete to the mock T cells. Furthermore, we found that the CAR-T cells with dectin-1 show distinct phenotype and exhaustion marker expression. These collective results suggest that the incorporation of this new signaling domain, dectin-1, into the CARs may provide the clinical potential of the CAR-T cells through this signaling domain in treating solid tumors.

Accurate interpretations and comparisons of record linkage results across jurisdictions require valid and reliable matching methods. We compared existing matching methods used by 6 US state and local health departments (Houston, Texas; Louisiana; Michigan; New York, New York; North Dakota; and Wisconsin) to link human immunodeficiency virus and viral hepatitis surveillance data with a 14-key automated, hierarchical deterministic matching method. Applicable years of study varied by disease and jurisdiction, ranging from 1979 to 2016. We calculated percentage agreement and Cohen's κ coefficient to compare the matching methods used within each jurisdiction. We calculated sensitivity, specificity, and positive predictive value for each matching method, as compared with a new standard that included manual review of discrepant cases. Agreement between the existing matching method and the deterministic matching method was 99.6% or higher in all jurisdictions; Cohen's κ values ranged from 0.87 to 0.98. The sensitivity of the deterministic matching method ranged from 97.4% to 100% in the 6 jurisdictions; specificity ranged from 99.7% to 100%; and positive predictive value ranged from 97.4% to 100%. Although no gold standard exists, prior assessments of existing methods and review of discrepant classifications suggest good accuracy and reliability of our deterministic matching method, with the advantage that our method reduces the need for manual review and allows for standard comparisons across jurisdictions when linking human immunodeficiency virus and viral hepatitis data.

Previous research has demonstrated that false memories produced by the Deese–Roediger–McDermott paradigm serve adaptive functions both in related memory tasks and in various cognitive processes. The present study investigated whether memory errors induced by associated words could influence performance on verbal reasoning tasks. Participants were asked to solve sentence-based verbal reasoning problems, half of which had been primed by the presentation of word lists where the critical lures were also the solutions to the problems. The results showed that when false memories were generated, problems were solved more often and significantly faster than those that were primed without false memories or those that were unprimed, and that there was no evidence that the effect of priming with false memories observed in experiments was due to testing effects. The findings extend false memory priming effects to verbal reasoning processes, providing evidence with adaptive constructive processes.

T cells in the immune system protect the human body from infection by pathogens and clear mutant cells through specific recognition by T cell receptors (TCRs). Cancer immunotherapy, by relying on this basic recognition method, boosts the antitumor efficacy of T cells by unleashing the inhibition of immune checkpoints and expands adaptive immunity by facilitating the adoptive transfer of genetically engineered T cells. T cells genetically equipped with chimeric antigen receptors (CARs) or TCRs have shown remarkable effectiveness in treating some hematological malignancies, although the efficacy of engineered T cells in treating solid tumors is far from satisfactory. In this review, we summarize the development of genetically engineered T cells, outline the most recent studies investigating genetically engineered T cells for cancer immunotherapy, and discuss strategies for improving the performance of these T cells in fighting cancers.

Interleukin-18 (IL-18) has been demonstrated to augment the antitumor capacity of chimeric antigen receptor-T cells (CAR-T) but the underlying mechanisms are largely unknown. Here we explored the effects and mechanisms of exogenous IL-18 on the antitumor response of CAR-T cells. IL-18 boosted the cytotoxicity of human epidermal growth factor receptor-2 (HER2)-specific CAR-T cells ex vivo and enhanced the antitumor efficacy of the CAR-T cells in immunodeficient mice, moreover, IL-18 improved the antitumor capacity of OVA-specific T cells in immunocompetent mice, indicating the universal enhancing function of IL-18 for adoptive cell therapy. To address the roles of IL-18 receptor (IL-18R) in the enhancing function, we evaluated the effects of IL-18R knockout (IL-18R-/-) condition in immunocompetent host and CAR-T cells on the IL-18-enhanced antitumor activities. Interestingly, IL-18 persisted to improve the antitumor ability of IL-18R intact CAR-T cells in IL-18R-/- mice. For IL-18R-/- CAR-T cells, however, IL-18 still holds the enhancing ability to boost the antitumor efficacy in IL-18R-/- mice, albeit the ex vivo tumor-killing ability was lower than that of IL-18R intact CAR-T cells, indicating that IL-18R-independent pathway is involved in the enhancement. Furthermore, tagged IL-18 binded to the membrane of IL-18R-/- splenic and lymph node cells and IL-18R intact and IL-18R-/- CAR-T cells showed distinct transcriptomic profiles when stimulated by IL-18. These data demonstrate that IL-18R-independent pathways contribute to functions of IL-18.

Due to the weak coordination of alkaline−earth metal ions (such as Mg2+, Ca2+ and Sr2+), the design for corresponding fluorescent probes in vitro is much harder than those for heavy metal ions (such as Cu2+, Hg2+ and Pb2+). In this paper, the crown ether-like structure was introduced in graphene quantum dots (C-GQDs) via the hydrothermal treatment of alizarin. With the strong coordination of crown ether-like structure in C-GQDs’ lattice, C-GQDs show much lower detection limit to Ca2+ (2 pM) than that of surface modified graphene quantum dots (100 pM). Moreover, the selectivity of C-GQDs can be controlled by the size modulation of crown ether-like structure. Precursors with different structures were carried out to modulate the size of crown ether-like structure in C-GQDs. The obtained C-GQDs show good selectivity for Mg2+, Sr2+, and Ba2+, respectively. Finally, we also show the successful detection of Ca2+ in vitro based on C-GQDs.

To construct a knowledge platform of acupuncture ancient books based on data mining technology, and to provide retrieval service for users.The Oracle 10 g database was applied and JAVA was selected as development language; based on the standard library and ancient books database established by manual entry, a variety of data mining technologies, including word segmentation, speech tagging, dependency analysis, rule extraction, similarity calculation, ambiguity analysis, supervised classification technology were applied to achieve text automatic extraction of ancient books; in the last, through association mining and decision analysis, the comprehensive and intelligent analysis of disease and symptom, meridians, acupoints, rules of acupuncture and moxibustion in acupuncture ancient books were realized, and retrieval service was provided for users through structure of browser/server (B/S).The platform realized full-text retrieval, word frequency analysis and association analysis; when diseases or acupoints were searched, the frequencies of meridian, acupoints (diseases) and techniques were presented from high to low, meanwhile the support degree and confidence coefficient between disease and acupoints (special acupoint), acupoints and acupoints in prescription, disease or acupoints and technique were presented.The experience platform of acupuncture ancient books based on data mining technology could be used as a reference for selection of disease, meridian and acupoint in clinical treatment and education of acupuncture and moxibustion.

Detecting weld seams and accurately locating them from time-series images that contain strong noise pollution are difficult and lead to reduced tracking accuracy. To address this problem, this paper presents a seam detection and tracking algorithm from the perspective of seam feature extraction and seam detection and positioning. The proposed image-processing algorithm employs the powerful feature expression capability and self-learning function of the deep convolutional neural network. A real-time weld seam searching and positioning strategy based on the multi-correlation filter cooperative detection mechanism is proposed in consideration of the continuity of the motion of the feature points of adjacent frames and the correlation of laser stripe structural information. Experimental results show that the sensor's measurement frequency can reach 20 Hz, the average absolute tracking error of straight or curved welds is less than 0.25 mm, and the maximum tracking error does not exceed 1 mm in an environment with strong arc and splash noise. Moreover, the welding torch end runs smoothly during welding. The proposed strategy can meet high-quality welding requirements.

The hierarchical photocatalysts of Ag–AgCl@Bi20TiO32 composites have been successfully synthesized by anchoring Ag–AgCl nanocrystals on the surfaces of mesoporous single-crystalline metastable Bi20TiO32 nanosheets via a two-stage strategy for excellent visible-light-driven photocatalytic activities in the Z-scheme system. First, the single-crystalline metastable Bi20TiO32 nanosheets with tetragonal structures were prepared via a facile hydrothermal process in assistance with the post-heat-treatment route using benzyl alcohol. Especially, the mesoporous Bi20TiO32 nanosheets showed high photocatalytic activity for the degradation of rhodamine B dye under visible-light irradiation. Then, the as-prepared mesoporous Bi20TiO32 nanosheets were used as a support for loading Ag–AgCl nanocrystals using the deposition–precipitation method and irradiation–reduction process to fabricate the Ag–AgCl@Bi20TiO32 composites. Inspiringly, the hierarchical Ag–AgCl@Bi20TiO32 photocatalyst has the higher photocatalytic perform...

This population based surveillance data was used to access the usage of dating sites and social networking sites in newly diagnosed HIV positive MSM's living in Harris County. Study findings indicates that young MSM's prefers to use dating sites than social networking sites due to it's anonymity and easy accessiblity through various mediums like computers, mobile apps etc.

Taking into account the linear loss of silicon-on-insulator (SOI) waveguide, modulation instability (MI) induced by combined effects of self-phase modulation and waveguide dispersions is investigated. The impacts of various parameters to gain spectra of MI are analyzed theoretically, and direct numerical simulation of nonlinear Schroedinger equation is performed as well. Results show that strong MI takes place even in the existence of low light power. The linear loss of waveguide obviously impacts gain spectra of MI, even within ultra-short propagation distance. The peak gain frequency and bandwidth of gain spectra decrease to 41.683% and 41.6879% of their maximum at propagation distance z = 5 mm, respectively.

Taking into account the small linear loss of silicon-on-insulator(SOI) waveguide, conditions and gain spectra of modulation instability(MI) induced by combined effects of self-phase modulation and waveguide dispersions are investigated. The impacts of various parameters to gain spectra of MI are analyzed theoretically. Results show that strong MI takes place even in the existence of low light power. The MI peak gain is 2 to 3 orders of magnitude larger than that achieved in optical fibers with the same light power. The linear loss of waveguide impacts gain spectra of MI, even within ultra-short propagation distance. The peak gain, peak gain frequency and bandwidth of gain spectra decrease to 66.828%, 41.683% and 41.6879% of their maxima at propagation distance z = 5mm, respectively.

A novel architecture of optical code (OC) label generation and recognition for optical packet switching (OPS) by using super structured fiber Bragg grating (SSFBG) is proposed. The OC label is generated and recognized by a label generator and recognizer, respectively. The label generator is composed of N encoders in parallel, and it can generate 2N kinds of serial optical code labels (SOCLs) for indicating 2N network routing information. The label recognizer can decode SOCLs by N decoders in parallel and provides label information to the switching control unit so that clock information is not required during the decoding process. In the switch nodes, handling of the high-speed information payload stream and the recognition of the OC label are performed in the optical domain, while processing of the routing information remains in the electrical domain. This approach could be a promising solution for an OPS network with high capacity, good quality of service (QoS), multi-service function and high security. In this experiment, we demonstrate 40 Gbps 256 label optical packet switching that employs clockless SOCL processing.

A waveguide-based chip-to-chip optical interconnection network on printed circuit board (PCB) was designed and fabricated, and experiments confirmed that the data rate in each channel could reach above 3.125 Gbit/s and the bit error rate (BER) could be up to 1.27×10−18, which would be a good solution to solve the communication bottlenecks between high-speed very large scale integration chips. Besides, the whole design and fabrication of optical interconnection network on printed circuit board has the advantages of high reliable, low cost and ease of manufacture.

A new method, named as doctor-blading, is presented to fabricate light waveguides in electro-optical printed circuit board (EOPCB). This new technology is proven to be suitable for the fabrication of the large size waveguides. The performance parameters of the light waveguides fabricated by the proposed method as well as the influence of the parameters on the performance of the waveguides are analyzed and simulated. The results demonstrate the feasibility of the method to fabricate the polymer waveguides.

Platelet-activating factor (PAF) is implicated in pathogenesis of chronic hypoxia-induced pulmonary hypertension in some animal models and in neonates. Effects of chronic hypoxia on PAF receptor (PAF-R) system in fetal pulmonary vasculature are unknown. We investigated the effect of chronic high altitude hypoxia (HAH) in fetal lambs [pregnant ewes were kept at 3,801 m (12,470 ft) altitude from ∼35 to 145 days gestation] on PAF-R-mediated effects in the pulmonary vasculature. Age-matched controls were kept at sea level. Intrapulmonary arteries were isolated, and smooth muscle cells (SMC-PA) were cultured from HAH and control fetuses. To determine presence of pulmonary vascular remodeling, lung tissue sections were subjected to morphometric analysis. Percentage medial wall thickness was significantly increased ( P < 0.05) in arteries at all levels in the HAH lambs. PAF-R protein expression studied by immunocytochemistry and Western blot analysis on lung tissue SMC-PA demonstrated greater PAF-R expression in HAH lambs. PAF-R binding (femtomoles per 106cells) in HAH SMC-PA was 90.3 ± 4.08 and 66% greater than 54.3 ± 4.9 in control SMC-PA. Pulmonary arteries from HAH fetuses synthesized >3-fold PAF than vessels from controls. Compared with controls SMC-PA of HAH lambs demonstrated 139% and 40% greater proliferation in 10% FBS alone and with 10 nM PAF, respectively. Our data demonstrate that exposure of ovine fetuses to HAH will result in significant upregulation of PAF synthesis, PAF-R expression, and PAF-R-mediated effects in pulmonary arteries. These findings suggest that increased PAF-R protein expression and increased PAF binding contribute to pulmonary vascular remodeling in these animals and may predispose them to persistent pulmonary hypertension after birth.

We previously reported that hypoxia attenuates cGMP-dependent protein kinase (PKG)-mediated relaxation in pulmonary vessels ( Am J Physiol Lung Cell Mol Physiol 279: L611–L618, 2003). To determine whether hypoxia-induced reactive oxygen and nitrogen species (ROS and RNS, respectively) may be involved in the downregulation of PKG-mediated relaxation, ovine fetal intrapulmonary veins were exposed to 4 h of normoxia or hypoxia, with or without scavengers of ROS [ N-acetylcysteine (NAC)] or peroxynitrite (quercetin and Trolox) and preconstricted with endothelin-1. Hypoxia decreased the relaxation response to 8-bromo-cGMP, PKG protein expression, and kinase activity and increased tyrosine nitration in PKG. However, ROS and RNS scavengers prevented these changes. To determine whether increased PKG nitration diminishes PKG activity, pulmonary vein smooth muscle cells (PVSMC) were exposed to shorter-term (30 min) hypoxia, which increased PKG nitration and decreased PKG activity but did not alter PKG protein expression. Increased dihydro-2,7-dichlorofluorescein diacetate (DCFH2-DA) fluorescence in PVSMC after 4 h or 30 min of hypoxia was not observed in the presence of NAC, quercetin, or Trolox, suggesting increased ROS and RNS production. Increased PKG nitration and the associated decrease in PKG activity in PVSMC after 30 min of hypoxia were also reversed on reoxygenation. The consequences of PKG nitration were assessed by exposure of purified PKG-Iα to peroxynitrite, which caused increased 3-nitrotyrosine immunoreactivity and inhibition of kinase activity. Our data suggest that, after 30 min of hypoxia, reversible covalent modification of PKG by hypoxia-induced reactive species may be an important mechanism by which the relaxation response to cGMP is regulated. However, after 4 h of hypoxia, PKG nitration and decreased PKG expression are involved.

Chronic hypoxia triggers pulmonary vascular remodeling, which is associated with a modulation of the vascular smooth muscle cell (SMC) phenotype from a contractile, differentiated to a synthetic, dedifferentiated state. We previously reported that acute hypoxia represses cGMP-dependent protein kinase (PKG) expression in ovine fetal pulmonary venous SMCs (FPVSMCs). Therefore, we tested if altered expression of PKG could explain SMC phenotype modulation after exposure to hypoxia. Hypoxia-induced reduction in PKG protein expression strongly correlated with the repressed expression of SMC phenotype markers, myosin heavy chain (MHC), calponin, vimentin, alpha-smooth muscle actin (alphaSMA), and thrombospondin (TSP), indicating that hypoxic exposure of SMC induced phenotype modulation to dedifferentiated state, and PKG may be involved in SMC phenotype modulation. PKG-specific small interfering RNA (siRNA) transfection in FPVSMCs significantly attenuated calponin, vimentin, and MHC expression, with no effect on alphaSMA and TSP. Treatment with 30 microM Drosophila Antennapedia (DT-3), a membrane-permeable peptide inhibitor of PKG, attenuated the expression of TSP, MHC, alphaSMA, vimentin, and calponin. The results from PKG siRNA and DT-3 studies indicate that hypoxia-induced reduction in protein expression was also similarly impacted by PKG inhibition. Overexpression of PKG in FPVSMCs by transfection with a full-length PKG construct tagged with green fluorescent fusion protein (PKG-GFP) reversed the effect of hypoxia on the expression of SMC phenotype marker proteins. These results suggest that PKG could be one of the determinants for the expression of SMC phenotype marker proteins and may be involved in the maintenance of the differentiated phenotype in pulmonary vascular SMCs in hypoxia.

An increase in Rho kinase (ROCK) activity is implicated in chronic hypoxia-induced pulmonary hypertension. In the present study, we determined the role of ROCKs in cGMP-dependent protein kinase (PKG)-mediated pulmonary vasodilation of fetal lambs exposed to chronic hypoxia. Fourth generation pulmonary arteries were isolated from near-term fetuses ( approximately 140 days of gestation) delivered from ewes exposed to chronic high altitude hypoxia for approximately 110 days and from control ewes. In vessels constricted to endothelin-1, 8-bromoguanosine-cGMP (8-Br-cGMP) caused a smaller relaxation in chronically hypoxic (CH) vessels compared with controls. Rp-8-Br-PET-cGMPS, a PKG inhibitor, attenuated relaxation to 8-Br-cGMP in control vessels to a greater extent than in CH vessels. Y-27632, a ROCK inhibitor, significantly potentiated 8-Br-cGMP-induced relaxation of CH vessels and had only a minor effect in control vessels. The expression of PKG was increased but was not accompanied with an increase in the activity of the enzyme in CH vessels. The expression of type II ROCK and activity of ROCKs were increased in CH vessels. The phosphorylation of threonine (Thr)696 and Thr850 of the regulatory subunit MYPT1 of myosin light chain phosphatase was inhibited by 8-Br-cGMP to a lesser extent in CH vessels than in controls. The difference was eliminated by Y-27632. These results suggest that chronic hypoxia in utero attenuates PKG-mediated relaxation in pulmonary arteries, partly due to inhibition of PKG activity and partly due to enhanced ROCK activity. Increased ROCK activity may inhibit PKG action through increased phosphorylation of MYPT1 at Thr696 and Thr850.

Summary Objective To investigate the resistance of Escherichia coli and Klebsiella pneumoniae producing extended-spectrum β-lactamases (ESBLs) and the genotyping of ESBLs in China. Methods MICs of 12 antibiotics against 50 strains (by random selection) of ESBLs-producing E. coli and K. pneumoniae were determined by E -test. The genotypes of ESBLs were analyzed by PCR, DNA sequencing and isoelectric focusing. Results The susceptibility rate of 50 isolates was 100% in imipenem, 60%–80% in cefoperazone/sulbactam, ceftazidime and piperacillin/tazobactam, and lower in other antimicrobial agents tested. Only 6.0% of the isolates were sensitive to cefotaxime. Four hundred and forty-seven of 509 isolates had been confirmed the genotype of ESBLs. Four hundred and sixteen strains produced only one type of ESBLs, including CTX-M-14 (271 strains), CTX-M-3 (70 strains), CTX-M-24 (35 strains), CTX-M-22 (8 strains), CTX-M-15 (4 strains), CTX-M-9 (4 strains), CTX-M-28 (3 strains), CTX-M-12 (1 strain), CTX-M-13 (1 strain), CTX-M-27 (1 strain), CTX-M-29 (1 strain), SHV-12 (10 strains), SHV-5 (4 strains), SHV-2 (2 strains), and SHV-9 (1 strain). Thirty isolates carried two or three types of ESBLs, and producing CTX-M-14 and CTX-M-3 together were the most common type. Conclusion The resistance of E. coli and K. pneumonia producing ESBLs in China was a serious issue and CTX-M type ESBLs were the most common genotype. CTX-M-14 was the predominant genotype. Some isolates produced two or three ESBLs.

Pericytes are known to regulate brain capillary endothelial functions. The purpose of this study was to define the hemostatic regulatory role of human brain pericytes. We used blood–brain barrier models consisting of human pericytes grown on transwell membrane inserts and cocultured with human brain microvascular endothelial cells (HBEC), or pericytes grown in direct contact with HBEC. When grown in cocultures in which pericytes were physically separated from endothelial cells, pericytes induced significant changes in endothelial tissue plasminogen activator (tPA) messenger ribonucleic acid (mRNA) and protein: tPA mRNA level was decreased in pericyte cocultures (52% ± 25% of monocultures, P < 0.05) and tPA protein level was decreased (66% ± 23% of monocultures, P < 0.05). Pericyte effects on endothelial fibrinolysis were enhanced when the two cell types were cocultured in direct contact, with tPA protein reduced in cocultures compared with monocultures (25% ± 15% of monocultures, P < 0.05). Endotoxin (lipopolysaccharide (LPS)), used as a standardized stimulus to define brain-specific inflammation-induced change, amplified pericyteinduced enhanced release of the tPA inhibitor plasminogen activator inhibitor-1 (PAI-1); the latter was released by endothelial cells first cocultured with pericytes and then incubated with LPS in the absence of pericytes. Pericytes (in contrast to endothelial cells and astrocytes) were found to be the principal in vitro source of the serpin protease nexin-1 (PN-1), known to have primarily antithrombin effects. These in vitro findings suggest that pericytes negatively regulate brain endothelial cell fibrinolysis, while pericyte expression of PN-1 may provide endogenous anticoagulant activity.

0049-3848/$ see front matter D 2004 Elsevier Ltd. All rights reserv doi:10.1016/j.thromres.2004.10.001 * Corresponding author. Department of Neurology, UC Irvine Me Orange, CA 92868-5120, United States. Tel.: +1 714 456 6808; fax: + E-mail address: mfisher@uci.edu (M. Fisher). in both thromboembolic and nonthrombotic stroke models produces reduced infarct size [4,5]. Moreover, tPA treatment has demonstrated efficacy in improving clinical outcome in acute ischemic stroke [6]. Stroke prevention therapy has focused primarily on inhibition of various components of platelet activation, with limited emphasis on the hemostatic regulatory role of the endothelium. Dipyridamole (DP) is a commonly used agent for stroke prevention that is thought to exert its effects by platelet antiaggregation action [7]. The ESPS-2 study demonstrated that DP, alone or in combination with aspirin, significantly reduced the risk of recurrent stroke [7]. The mechanism of action for DP has been incompletely understood, and we hypothesized that DP regulates brain capillary endothelial fibrinolysis. Thrombosis Research (2005) 115, 435—438