From the Blood to the Central Nervous System: A Nanoparticle's Journey Through the Blood-Brain Barrier by Transcytosis

Designing nanoparticles that effectively enter the central nervous system (CNS) rapidly and without alteration is one of the major challenges in the use of nanotechnology for the brain. In this chapter, we explore the process of transcytosis, a receptor-mediated transport pathway that permits endogenous macromolecules to enter the CNS by crossing the blood-brain barrier. Transcytosis across the blood-brain barrier involves a number of distinct stages, including receptor binding, endocytosis into a transport vesicle, trafficking of the vesicle to the opposite side of the cell, and finally exocytosis and release of cargo. For each stage, we discuss the current knowledge on biological, physiological, and physical factors that influence nanoparticle transit through that stage of transcytosis, with implications for nanoparticle design. Finally, we look at the current progress in designing nanoparticles that exploit transcytosis for CNS delivery.

First Measurement of Electron Neutrino Appearance in NOvA

We report results from the first search for ν_{μ}→ν_{e} transitions by the NOvA experiment. In an exposure equivalent to 2.74×10^{20} protons on target in the upgraded NuMI beam at Fermilab, we observe 6 events in the Far Detector, compared to a background expectation of 0.99±0.11(syst) events based on the Near Detector measurement. A secondary analysis observes 11 events with a background of 1.07±0.14(syst). The 3.3σ excess of events observed in the primary analysis disfavors 0.1π<δ_{CP}<0.5π in the inverted mass hierarchy at the 90% C.L.

Cardioprotection against experimental myocardial ischemic injury using cornin

Phosphorylated-cyclic adenosine monophosphate response element-binding protein (Phospho-CREB) has an important role in the pathogenesis of myocardial ischemia. We isolated the iridoid glycoside cornin from the fruit of Verbena officinalis L, investigated its effects against myocardial ischemia and reperfusion (I/R) injury in vivo, and elucidated its potential mechanism in vitro. Effects of cornin on cell viability, as well as expression of phospho-CREB and phospho-Akt in hypoxic H9c2 cells in vitro, and myocardial I/R injury in vivo, were investigated. Cornin attenuated hypoxia-induced cytotoxicity significantly in H9c2 cells in a concentration-dependent manner. Treatment of H9c2 cells with cornin (10 µM) blocked the reduction of expression of phospho-CREB and phospho-Akt in a hypoxic condition. Treatment of rats with cornin (30 mg/kg, iv) protected them from myocardial I/R injury as indicated by a decrease in infarct volume, improvement in hemodynamics, and reduction of severity of myocardial damage. Cornin treatment also attenuated the reduction of expression of phospho-CREB and phospho-Akt in ischemic myocardial tissue. These data suggest that cornin exerts protective effects due to an increase in expression of phospho-CREB and phospho-Akt.

Chinese SLE Treatment and Research group (CSTAR) registry VII: prevalence and clinical significance of serositis in Chinese patients with systemic lupus erythematosus

Objectives

To investigate both the prevalence and clinical characteristics of serositis in Chinese patients with systemic lupus erythematosus (SLE) in a large cohort in the Chinese SLE Treatment and Research group (CSTAR) database.

Methods

A prospective cross-sectional study of patients with SLE was conducted based on the data from the CSTAR registry. Serositis was defined according to the 1999 revised American College of Rheumatology (ACR) criteria for SLE – that is, pleuritis/pleural effusion and/or pericarditis/pericardial effusion detected by echocardiography, chest X-ray or chest computerized tomography (CT) scan. Peritonitis/peritoneal effusion were confirmed by abdominal ultrasonography. We analysed the prevalence and clinical associations of serositis with demographic data, organ involvements, laboratory findings and SLE disease activity.

Results

Of 2104 patients with SLE, 345 were diagnosed with serositis. The prevalence of lupus nephritis (LN), interstitial lung disease and pulmonary arterial hypertension, as well as the presence of leukocytopenia, thrombocytopenia, hypocomplementemia and anti-dsDNA antibodies was significantly higher in patients with serositis ( P < 0.05). Significantly higher SLE disease activity scores were found in patients with serositis compared to those patients without serositis ( P < 0.05). Lupus-related peritonitis had similar clinical manifestations and laboratory profiles as serositis caused by SLE.

Conclusions

There is a significant association of nephropathy, interstitial lung disease, pulmonary arterial hypertension, hypocomplementemia, leukocytopenia, thrombocytopenia and elevated anti-dsDNA antibodies with serositis. The results suggest that higher SLE disease activity contributes to serositis development, and should be treated aggressively.

32 EFFECTS OF HIGH HYDROSTATIC PRESSURE ON EXPRESSION PROFILES OF IN VITRO-PRODUCED, VITRIFIED BOVINE BLASTOCYSTS

High hydrostatic pressure (HHP) has been used to enhance stress tolerance and to promote embryo survival before they are subjected to insulting procedures such as cryopreservation. However, the molecular mechanisms of the beneficial effects of HHP are poorly understood. Here in vitro-produced bovine blastocysts were treated with 40, 60, and 80 MPa of HHP for 1 h at either 25 or 37°C, followed by 3 different recovery periods (0, 1, and 2 h) after HHP before vitrification by the solid surface vitrification method (Dinnyes et al. 2000). The re-expansion rates after vitrification-warming were significantly (P < 0.05) higher in embryos treated with 40 or 60 MPa than controls, demonstrating that HHP promotes the in vitro developmental competence of vitrified bovine embryos. However, 80 MPa resulted in significantly reduced re-expansion rates, suggesting that this pressure started to be lethal to bovine blastocysts. In addition, no significant difference was found on re-expansion rates between 25 and 37°C; data were therefore combined for the 2 temperatures. Microarray analysis revealed a total of 399 differentially expressed transcripts, representing 254 unique genes, among different treatment groups. Gene ontology analysis revealed that HHP at 40 and 60 MPa promoted embryo competence through down-regulation of genes involved in cell death and apoptosis, and up-regulation of RNA processing, cellular growth, and proliferation. Moreover, gene expression was also changed by the length of the recovery time after HHP. The significantly over-represented groups are apoptosis and cell death in the 1-h group, and protein folding, response to unfolded protein, and cell cycle in the 2-h group. Although 80 MPa also up-regulated expression of genes for apoptosis, but it also significantly down-regulated genes for protein folding and cell cycle, which may explain why these embryos stopped developing. Taken together, these data suggest that HHP induces specific responses in vitrified bovine blastocysts and promotes their developmental competence through modest transcriptional reprogramming.

Meta-analysis comparing early versus delayed laparoscopic cholecystectomy for acute cholecystitis

BACKGROUND

Previous studies comparing early laparoscopic cholecystectomy (ELC) with delayed laparoscopic cholecystectomy (DLC) for acute cholecystitis were incomplete. A meta-analysis was undertaken to compare the cost-effectiveness, quality of life, safety and effectiveness of ELC versus DLC.

METHODS

PubMed, Embase, the Cochrane Library and Web of Science were searched for randomized clinical trials (RCTs) that compared ELC (performed within 7 days of symptom onset) with DLC (undertaken at least 1 week after symptoms had subsided) for acute cholecystitis.

RESULTS

Sixteen studies reporting on 15 RCTs comprising 1625 patients were included. Compared with DLC, ELC was associated with lower hospital costs, fewer work days lost (mean difference (MD) -11·07 (95 per cent c.i. -16·21 to -5·94) days; P < 0·001), higher patient satisfaction and quality of life, lower risk of wound infection (relative risk 0·65, 95 per cent c.i. 0·47 to 0·91; P = 0·01) and shorter hospital stay (MD -3·38 (-4·23 to -2·52) days; P < 0·001), but a longer duration of operation (MD 11·12 (4·57 to 17·67) min; P < 0·001). There were no significant differences between the two groups in mortality, bile duct injury, bile leakage, conversion to open cholecystectomy or overall complications.

CONCLUSION

For patients with acute cholecystitis, ELC appears as safe and effective as DLC. ELC might be associated with lower hospital costs, fewer work days lost, and greater patient satisfaction.

Activation of the SIRT1/p66shc antiapoptosis pathway via carnosic acid-induced inhibition of miR-34a protects rats against nonalcoholic fatty liver disease

Recent studies have demonstrated that miR-34a expression is significantly upregulated and associated with apoptosis in nonalcoholic fatty liver disease (NAFLD). Carnosic acid (CA) is a novel antioxidant and a potential inhibitor of apoptosis in organ injury, including liver injury. This study aimed to investigate the signaling mechanisms underlying miR-34a expression and the antiapoptotic effect of CA in NAFLD. CA treatment significantly reduced the high-fat diet (HFD)-induced elevations in aminotransferase activity as well as in serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and malondialdehyde (MDA) levels but increased serum high-density lipoprotein cholesterol (HDL-C) and hepatic superoxide dismutase (SOD) levels. Moreover, CA treatment ameliorated the increase in cleaved caspase-3 caused by HFD exposure and completely reversed the HFD-induced decreases in manganese superoxide dismutase (MnSOD) and B-cell lymphoma-extra large expression. CA also counteracted the HFD- or palmitic acid (PA)-induced increases in caspase-3 and caspase-9 activity. Mechanistically, CA reversed the HFD- or PA-induced upregulation of miR-34a, which is the best-characterized regulator of SIRT1. Importantly, the decrease in miR-34a expression was closely associated with the activation of the SIRT1/p66shc pathway, which attenuates hepatocyte apoptosis in liver ischemia/reperfusion injury. A dual luciferase assay in L02 cells validated the modulation of SIRT1 by CA, which occurs at least partly via miR-34a. In addition, miR-34a overexpression was significantly counteracted by CA, which prevented the miR-34a-dependent repression of the SIRT1/p66shc pathway and apoptosis. Collectively, our results support a link between liver cell apoptosis and the miR-34a/SIRT1/p66shc pathway, which can be modulated by CA in NAFLD.

Functional pseudogenes inhibit the superoxide production

We recently discovered a dynamic copy number variation on the NCF1 (neutrophil cytosolic factor 1) pseudogenes in human populations. In this study, we investigated whether these pseudogenes are functional or junk as described before. We sequenced the RNAs transcribed from the genome of this locus, and discovered over 10 splicing isoforms from the NCF1 pseudogenes. We cloned 4 splicing isoforms into expression vectors and introduced them into human vascular endothelial cells by transient transfection. We then used two chemical approaches to measure the superoxide production in the cells with and without these pseudogene overexpression. Our data showed that three pseudogene splicing products remarkably reduced the superoxide production after the GFP (Green fluorescent protein) normalization. We used an anti-HA (Hemagglutinin A) tag antibody to stain the cells and confirmed that the proteins transcribed from the NCF1 pseudogene were exclusively localized in the cytoplasm in the perinuclear area in the transient transfection assays. We further examined the tissue distribution of these splicing isoforms of NCF1 pseudogenes in human tissues by quantitative real-time PCR analysis. Our data showed that although these splicing variants are ubiquitously expressed in non-immune tissues in human, they seem to be under a tight control of transcription regulation and show a non-random distribution pattern across tissues. This study challenges the concept that pseudogenes in human genome are only junks without biological functions. Moreover, it suggests that those pseudogenes in human genome may serve as a natural resource for novel drug discovery.

Rapid sedation induced by fentanyl combined with propofol via an intrathecal chemotherapy injection for leukemia in children

This study explored the sedative and analgesic effects of fentanyl combined with propofol via an intrathecal chemotherapy injection for acute leukemia (acute lymphocytic leukemia or acute myelocytic leukemia) among children, to relieve pain and difficulty during intrathecal injection, improve treatment compliance, increase the success rate of single puncture, and reduce procedure failure, with the aim of developing a painless procedure for children with acute leukemia. Fifty person-times received fentanyl combined with propofol via an intrathecal chemotherapy injection among the hospitalized children with leukemia. The patients' cooperation with the procedure, response to the medication, dosages of fentanyl and propofol, reaction to the procedures, wake-up time, and changes in oxygen saturation (SpO2), heart rate (HR), respiration, and blood pressure (BP) before, during, and after the procedures were observed. The doctors who performed the procedures assessed the quality of sedation and analgesia. In the treatment group, the patients were quiet during the lumbar puncture and intrathecal injection, showing good sedation and analgesia. HR and respiration decreased slightly. There were no changes in SpO2 and BP. No obvious respiratory depression occurred with proper dosages. Only a few patients showed stertorous respiration, which stopped soon after the procedures. In the control group, the patients were agitated, crying, and not cooperative before and during the procedures, which made the procedures very difficult. During intrathecal injection, pain obviously reduced and the success rate of single lumbar puncture increased. It is safe and effective to apply fentanyl combined with propofol for sedation and analgesia.

Which is more suitable for kidney transplantation at the early post-transplantation phase in China - low dosing or standard dosing of enteric-coated mycophenolate sodium?

AIMS

To investigate the pharmacokinetics of enteric-coated mycophenolate sodium (EC-MPS) and the clinical outcome in kidney transplant recipients in the early post-transplantation phase. Then explain which regimen is more suitable for Chinese renal transplant recipients.

METHODOLOGY

In total, 60 de novo kidney transplant recipients treated with tacrolimus and steroids were randomised to receive EC-MPS at standard dose (SD; 1440 mg/day; n = 28) or low dose (LD; 1080 mg/day; n = 32). Efficacy parameters, safety and tolerability were assessed over a 6-month study period. Full mycophenolic acid (MPA) areas under the curve (AUCs) were completed on days 3 and 5, whereas a three-point limited sampling strategy (LSS) was utilised for MPA AUC assessments at 2 weeks and months 1, 3 and 6 (the LSS for three-time-point MPA AUC 0-12 h (mg h/l) = 15.99 + 0.87C1 h  + 0.68C2 h  + 7.85C4 h ; r(2)  = 0.8670.

RESULTS

The mean AUC levels at day 3 and day 5 in the SD group were significantly higher than in the LD group (57.4 mg·h/l vs. 38.2 mg·h/l and 59.3 mg·h/l vs. 44.8 mg·h/l, respectively, p < 0.01). There was a trend for fewer clinically diagnosed acute rejections in the SD group vs. the LD group at 6 months (7.1% vs. 12.5%). This trend was also present when acute rejection was analysed as biopsy-proven cases. There were significantly more acute rejections (all definitions) in patients with MPA AUC levels < 30 mg·h/l compared with those with MPA AUC levels ≥ 30 mg·h/l within 6 months (p < 0.05). Renal function, incidence of infection and haematological disorders were not significantly different in either study group.

CONCLUSIONS

Early adequate MPA exposure in renal transplant recipients can be achieved with a higher starting dose. In addition, a SD regimen was as well-tolerated as a LD regimen. Furthermore, early adequate MPA exposure significantly lowered the rate of acute rejection without compromising safety and tolerability.