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1.  Current approaches to enhance CNS delivery of drugs across the brain barriers 
Although many agents have therapeutic potentials for central nervous system (CNS) diseases, few of these agents have been clinically used because of the brain barriers. As the protective barrier of the CNS, the blood–brain barrier and the blood–cerebrospinal fluid barrier maintain the brain microenvironment, neuronal activity, and proper functioning of the CNS. Different strategies for efficient CNS delivery have been studied. This article reviews the current approaches to open or facilitate penetration across these barriers for enhanced drug delivery to the CNS. These approaches are summarized into three broad categories: noninvasive, invasive, and miscellaneous techniques. The progresses made using these approaches are reviewed, and the associated mechanisms and problems are discussed.
PMCID: PMC4026551  PMID: 24872687
drug delivery system; blood–brain barrier (BBB); central nervous system; brain-targeted therapy; cerebrospinal fluid (CSF)
2.  Chinese SLE Treatment and Research Group Registry: III. Association of Autoantibodies with Clinical Manifestations in Chinese Patients with Systemic Lupus Erythematosus 
Journal of Immunology Research  2014;2014:809389.
We investigated the characteristics of Chinese SLE patients by analyzing the association between specific autoantibodies and clinical manifestations of 2104 SLE patients from registry data of CSTAR cohort. Significant (P < 0.05) associations were found between anti-Sm antibody, anti-rRNP antibody, and malar rash; between anti-RNP antibody, anti-SSA antibody, and pulmonary arterial hypertension (PAH); between anti-SSB antibody and hematologic involvement; and between anti-dsDNA antibody and nephropathy. APL antibody was associated with hematologic involvement, interstitial lung disease, and a lower prevalence of oral ulcerations (P < 0.05). Associations were also found between anti-dsDNA antibody and a lower prevalence of photosensitivity, and between anti-SSA antibody and a lower prevalence of nephropathy (P < 0.05). Most of these findings were consistent with other studies in the literature but this study is the first report on the association between anti-SSA and a lower prevalence of nephropathy. The correlations of specific autoantibodies and clinical manifestations could provide clues for physicians to predict organ damages in SLE patients. We suggest that a thorough screening of autoantibodies should be carried out when the diagnosis of SLE is established, and repeated echocardiography annually in SLE patients with anti-RNP or anti-SSA antibody should be performed.
PMCID: PMC4017718  PMID: 24864270
3.  Biomass Allocation Patterns across China’s Terrestrial Biomes 
PLoS ONE  2014;9(4):e93566.
Root to shoot ratio (RS) is commonly used to describe the biomass allocation between below- and aboveground parts of plants. Determining the key factors influencing RS and interpreting the relationship between RS and environmental factors is important for biological and ecological research. In this study, we compiled 2088 pairs of root and shoot biomass data across China’s terrestrial biomes to examine variations in the RS and its responses to biotic and abiotic factors including vegetation type, soil texture, climatic variables, and stand age. The median value of RS (RSm) for grasslands, shrublands, and forests was 6.0, 0.73, and 0.23, respectively. The range of RS was considerably wide for each vegetation type. RS values for all three major vegetation types were found to be significantly correlated to mean annual precipitation (MAP) and potential water deficit index (PWDI). Mean annual temperature (MAT) also significantly affect the RS for forests and grasslands. Soil texture and forest origin altered the response of RS to climatic factors as well. An allometric formula could be used to well quantify the relationship between aboveground and belowground biomass, although each vegetation type had its own inherent allometric relationship.
PMCID: PMC3977935  PMID: 24710503
4.  Functional Connectivity among Spikes in Low Dimensional Space during Working Memory Task in Rat 
PLoS ONE  2014;9(3):e91481.
Working memory (WM) is critically important in cognitive tasks. The functional connectivity has been a powerful tool for understanding the mechanism underlying the information processing during WM tasks. The aim of this study is to investigate how to effectively characterize the dynamic variations of the functional connectivity in low dimensional space among the principal components (PCs) which were extracted from the instantaneous firing rate series. Spikes were obtained from medial prefrontal cortex (mPFC) of rats with implanted microelectrode array and then transformed into continuous series via instantaneous firing rate method. Granger causality method is proposed to study the functional connectivity. Then three scalar metrics were applied to identify the changes of the reduced dimensionality functional network during working memory tasks: functional connectivity (GC), global efficiency (E) and casual density (CD). As a comparison, GC, E and CD were also calculated to describe the functional connectivity in the original space. The results showed that these network characteristics dynamically changed during the correct WM tasks. The measure values increased to maximum, and then decreased both in the original and in the reduced dimensionality. Besides, the feature values of the reduced dimensionality were significantly higher during the WM tasks than they were in the original space. These findings suggested that functional connectivity among the spikes varied dynamically during the WM tasks and could be described effectively in the low dimensional space.
PMCID: PMC3962371  PMID: 24658291
5.  Loss of cilia suppresses cyst growth in genetic models of autosomal dominant polycystic kidney disease 
Nature genetics  2013;45(9):1004-1012.
Kidney cysts occur following inactivation of polycystins in otherwise intact cilia or following complete removal of cilia by inactivation of intraflagellar transport-related proteins. We investigated the mechanisms of cyst formation in these two distinct processes by combining conditional inactivation of polycystins with concomitant ablation of cilia in developing and adult kidney and liver. We found that loss of intact cilia suppresses cyst growth following inactivation of polycystins and that the severity of cystic disease was directly related to the length of time between the initial loss of the polycystin proteins and the subsequent involution of cilia. This cilia-dependent cyst growth was not explained by activation of the MAPK/ERK, mTOR or cAMP pathways and is likely to be distinct from the mechanism of cyst growth following complete loss of cilia. The data establish the existence of a novel pathway defined by polycystin-dependent inhibition and cilia-dependent activation that promotes rapid cyst growth.
PMCID: PMC3758452  PMID: 23892607
6.  Contribution of Baicalin on the Plasma Protein Binding Displacement and CYP3A Activity Inhibition to the Pharmacokinetic Changes of Nifedipine in Rats In Vivo and In Vitro 
PLoS ONE  2014;9(1):e87234.
Baicalin purified from the root of Radix scutellariae is widely used in clinical practices. This study aimed to evaluate the effect of baicalin on the pharmacokinetics of nifedipine, a CYP3A probe substrate, in rats in vivo and in vitro. In a randomised, three-period crossover study, significant changes in the pharmacokinetics of nifedipine (2 mg/kg) were observed after treatment with a low (0.225 g/kg) or high (0.45 g/kg) dose of baicalin in rats. In the low- and high-dose groups of baicalin-treated rats, Cmax of total nifedipine decreased by 40%±14% (P<0.01) and 65%±14% (P<0.01), AUC0–∞ decreased by 41%±8% (P<0.01) and 63%±7% (P<0.01), Vd increased by 85%±43% (P<0.01) and 224%±231% (P<0.01), and CL increased by 97%±78% (P<0.01) and 242%±135% (P<0.01), respectively. Plasma protein binding experiments in vivo showed that Cmax of unbound nifedipine significantly increased by 25%±19% (P<0.01) and 44%±29% (P<0.01), respectively, and there was a good correlation between the unbound nifedipine (%) and baicalin concentrations (P<0.01). Furthermore, in vitro results revealed that baicalin was a competitive displacer of nifedipine from plasma proteins. In vitro incubation experiments demonstrated that baicalin could also competitively inhibit CYP3A activity in rat liver microsomes in a concentration-dependent manner. In conclusion, the pharmacokinetic changes of nifedipine may be modulated by the inhibitory effects of baicalin on plasma protein binding and CYP3A–mediated metabolism.
PMCID: PMC3907542  PMID: 24498050
7.  How can nanotechnology help membrane vesicle-based cancer immunotherapy development? 
Exosomes are nanosized vesicles originating from endosomal compartments and secreted by most living cells. In the past decade, exosomes have emerged as potent tools for cancer immunotherapy due to their important roles in modulation of immune responses, and promising results have been achieved in exosome-based immunotherapy. The recent rapid progress of nanotechnology, especially on tailored design of nanocarriers for drug delivery based on both passive and active targeting strategies, sheds light on re-engineering native membrane vesicles for enhanced immune regulation and therapy. Applications of nanotechnology toolkits might provide new opportunity not only for value-added therapeutic or diagnostic strategies based on exosomes in cancer immunotherapy, but also new insights for biogenesis and biological relevance of membrane vesicles. This commentary focuses on the recent development and limitations of using exosomes in cancer immunotherapy and our perspectives on how nanomaterials with potential immune regulatory effects could be introduced into exosome-based immunotherapy.
PMCID: PMC3667943  PMID: 23108359
immunotherapy; exosome; nanotechnology; dendritic cell; cancer vaccine
8.  Inhibition of Propofol Anesthesia on Functional Connectivity between LFPs in PFC during Rat Working Memory Task 
PLoS ONE  2013;8(12):e83653.
Working memory (WM) refers to the temporary storage and manipulation of information necessary for performance of complex cognitive tasks. There is a growing interest in whether and how propofol anesthesia inhibits WM function. The aim of this study is to investigate the possible inhibition mechanism of propofol anesthesia based on the functional connections of multi-local field potentials (LFPs) and behavior during WM tasks. Adult SD rats were randomly divided into 3 groups: pro group (0.5 mg·kg−1·min−1,2 h), PRO group (0.9 mg·kg−1·min−1, 2 h) and control group. The experimental data were 16-channel LFPs obtained at prefrontal cortex with implanted microelectrode array in SD rats during WM tasks in Y-maze at 24, 48, 72, 96, 120 hours (day 1-day 5) after propofol anesthesia, and the behavior results of WM were recoded at the same time. Directed transfer function (DTF) method was applied to analyze the connections among LFPs directly. Furthermore, the causal networks were identified by DTF. The clustering coefficient (C), network density (D) and global efficiency (Eglobal) were selected to describe the functional connectivity quantitatively. The results show that: comparing with the control group, the LFPs functional connectivity in pro group were no significantly difference (p>0.05); the connectivity in PRO group were significantly decreased (p<0.05 at 24 hours, p<0.05 at 48 hours), while no significant difference at 72, 96 and 120 hours for rats (p>0.05), which were consistent with the behavior results. These findings could lead to improved understanding the mechanism of inhibition of anesthesia on WM functions from the view of connections among LFPs.
PMCID: PMC3873953  PMID: 24386243
9.  Association Study of Germline Variants in CCNB1 and CDK1 with Breast Cancer Susceptibility, Progression, and Survival among Chinese Han Women 
PLoS ONE  2013;8(12):e84489.
The CCNB1 and CDK1 genes encode the proteins of CyclinB1 and CDK1 respectively, which interact with each other and are involved in cell cycle regulation, centrosome duplication and chromosome segregation. This study aimed to investigate whether the genetic variants in these two genes may affect breast cancer (BC) susceptibility, progression, and survival in Chinese Han population using haplotype-based analysis. A total of ten tSNPs spanning from 2kb upstream to 2kb downstream of these genes were genotyped in 1204 cases and 1204 age-matched cancer-free controls. The haplotype blocks were determined according to our genotyping data and linkage disequilibrium (LD) status of these SNPs. For CCNB1, rs2069429 was significantly associated with increased BC susceptibility under recessive model (OR=2.352, 95%CI=1.480-3.737), so was the diplotype TAGT/TAGT (OR=1.947 95%CI=1.154-3.284, P=0.013). In addition, rs164390 was associated with Her2-negative BC. For CDK1, rs2448343 and rs1871446 were significantly associated with decreased BC risk under dominant models, so was the haplotype ATATT. These two SNPs also showed a dose-dependent effect on BC susceptibility. Using stratified association analysis, we found that women with the heterozygotes or minor allele homozygotes of rs2448343 had much less BC susceptibility among women with BMI<23. In CDK1, three closely located SNPs, rs2448343, rs3213048 and rs3213067, were significantly associated with tumor’s PR status: the heterozygotes of rs2448343 were associated with PR-positive tumors, while the minor allele homozygotes of rs3213048 and heterozygotes of rs3213067 were associated with PR-negative BC tumors. In survival analysis, rs1871446 was associated with unfavorable event-free survival under recessive model, so was the CDK1 diplotype ATATG/ATATG, which carried the minor allele homozygote of rs1871446. Our study indicates that genetic polymorphisms of CCNB1 and CDK1 are related to BC susceptibility, progression, and survival in Chinese Han women. Further studies need to be performed in other populations as an independent replication to verify these results.
PMCID: PMC3873991  PMID: 24386390
10.  Gastrointestinal complications of systemic sclerosis 
Systemic sclerosis is an autoimmune disease characterized by progressive skin thickening and tightness. Pulmonary interstitial fibrosis and kidney damage are the most important indicators for mortality; however, the gastrointestinal tract is the most commonly damaged system. Virtually all parts of the gastrointestinal (GI) tract can be involved, although the esophagus is the most frequently reported. The mechanisms that cause such extensive damage are generally unclear, but vascular changes, immunological abnormalities, excessive accumulation of collagen in the submucosa, smooth muscle atrophy and neuropathy may participate because these are the most common histological findings in biopsies and autopsies. Most patients with GI tract involvement complain about dyspepsia, nausea, vomiting, abdominal bloating/distension, and fecal incontinence. These symptoms are generally mild during the early stage of the disease and are likely ignored by physicians. As the disease becomes more advanced, however, patient quality of life is markedly influenced, whereby malnutrition and shortened survival are the usual consequences. The diagnosis for systemic sclerosis is based on manometry measurements and an endoscopy examination. Supportive and symptomatic treatment is the main therapeutic strategy; however, an early diagnosis is critical for successful management.
PMCID: PMC3819541  PMID: 24222949
Systemic sclerosis; Gastrointestinal tract; Manometry; Endoscopy; Diagnosis; Treatment
11.  Correction: Evaluation of a Novel Thermosensitive Heparin-Poloxamer Hydrogel for Improving Vascular Anastomosis Quality and Safety in a Rabbit Model 
PLoS ONE  2013;8(10):10.1371/annotation/9ba3d2e7-10c6-4e5c-96a8-ac331b4c2a83.
PMCID: PMC3795082
12.  High Prevalence of Respiratory Ciliary Dysfunction in Congenital Heart Disease Patients With Heterotaxy 
Circulation  2012;125(18):2232-2242.
Patients with congenital heart disease (CHD) and heterotaxy show high postsurgical morbidity/mortality, with some developing respiratory complications. Although this finding is often attributed to the CHD, airway clearance and left-right patterning both require motile cilia function. Thus, airway ciliary dysfunction (CD) similar to that of primary ciliary dyskinesia (PCD) may contribute to increased respiratory complications in heterotaxy patients.
Methods and Results
We assessed 43 CHD patients with heterotaxy for airway CD. Videomicrocopy was used to examine ciliary motion in nasal tissue, and nasal nitric oxide (nNO) was measured; nNO level is typically low with PCD. Eighteen patients exhibited CD characterized by abnormal ciliary motion and nNO levels below or near the PCD cutoff values. Patients with CD aged >6 years show increased respiratory symptoms similar to those seen in PCD. Sequencing of all 14 known PCD genes in 13 heterotaxy patients with CD, 12 without CD, 10 PCD disease controls, and 13 healthy controls yielded 0.769, 0.417, 1.0, and 0.077 novel variants per patient, respectively. One heterotaxy patient with CD had the PCD causing DNAI1 founder mutation. Another with hyperkinetic ciliary beat had 2 mutations in DNAH11, the only PCD gene known to cause hyperkinetic beat. Among PCD patients, 2 had known PCD causing CCDC39 and CCDC40 mutations.
Our studies show that CHD patients with heterotaxy have substantial risk for CD and increased respiratory disease. Heterotaxy patients with CD were enriched for mutations in PCD genes. Future studies are needed to assess the potential benefit of prescreening and prophylactically treating heterotaxy patients for CD.
PMCID: PMC3770728  PMID: 22499950
genomic studies; heart defects; congenital; heterotaxy; nitric oxide; primary ciliary dyskinesia
13.  Correction: Evaluation of a Novel Thermosensitive Heparin-Poloxamer Hydrogel for Improving Vascular Anastomosis Quality and Safety in a Rabbit Model 
PLoS ONE  2013;8(9):10.1371/annotation/83ee5a05-d305-4a27-bf66-7e7dce37a85e.
PMCID: PMC3765452  PMID: 24039674
14.  Evaluation of a Novel Thermosensitive Heparin-Poloxamer Hydrogel for Improving Vascular Anastomosis Quality and Safety in a Rabbit Model 
PLoS ONE  2013;8(8):e73178.
Despite progress in the design of advanced surgical techniques, stenosis recurs in a large percentage of vascular anastomosis. In this study, a novel heparin-poloxamer (HP) hydrogel was designed and its effects for improving the quality and safety of vascular anastomosis were studied. HP copolymer was synthesized and its structure was confirmed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (1H-NMR). Hydrogels containing HP were prepared and their important characteristics related to the application in vascular anastomosis including gelation temperature, rheological behaviour and micromorphology were measured. Vascular anastomosis were performed on the right common carotid arteries of rabbits, and the in vivo efficiency and safety of HP hydrogel to achieve vascular anastomosis was verified and compared with Poloxamer 407 hydrogel and the conventional hand-sewn method using Doppler ultrasound, CT angiograms, scanning electron microscopy (SEM) and histological technique. Our results showed that HP copolymer displayed special gel-sol-gel phase transition behavior with increasing temperature from 5 to 60 °C. HP hydrogel prepared from 18 wt% HP solution had a porous sponge-like structure, with gelation temperature at approximately 38 °C and maximum elastic modulus at 10,000 Pa. In animal studies, imaging and histological examination of rabbit common jugular artery confirmed that HP hydrogel group had similar equivalent patency, flow and burst strength as Poloxamer 407 group. Moreover, HP hydrogel was superior to poloxamer 407 hydrogel and hand-sewn method for restoring the functions and epithelial structure of the broken vessel junctions after operation. By combining the advantages of heparin and poloxamer 407, HP hydrogel holds high promise for improving vascular anastomosis quality and safety.
PMCID: PMC3755001  PMID: 24015296
15.  Highly Heterogeneous Bacterial Communities Associated with the South China Sea Reef Corals Porites lutea, Galaxea fascicularis and Acropora millepora 
PLoS ONE  2013;8(8):e71301.
Coral harbor diverse and specific bacteria play significant roles in coral holobiont function. Bacteria associated with three of the common and phylogenetically divergent reef-building corals in the South China Sea, Porites lutea, Galaxea fascicularis and Acropora millepora, were investigated using 454 barcoded-pyrosequencing. Three colonies of each species were sampled, and 16S rRNA gene libraries were constructed individually. Analysis of pyrosequencing libraries showed that bacterial communities associated with the three coral species were more diverse than previous estimates based on corals from the Caribbean Sea, Indo-Pacific reefs and the Red Sea. Three candidate phyla, including BRC1, OD1 and SR1, were found for the first time in corals. Bacterial communities were separated into three groups: P. lutea and G. fascicular, A. millepora and seawater. P. lutea and G. fascicular displayed more similar bacterial communities, and bacterial communities associated with A. millepora differed from the other two coral species. The three coral species shared only 22 OTUs, which were distributed in Alphaproteobacteria, Deltaproteobacteria, Gammaproteobacteria, Chloroflexi, Actinobacteria, Acidobacteria and an unclassified bacterial group. The composition of bacterial communities within each colony of each coral species also showed variation. The relatively small common and large specific bacterial communities in these corals implies that bacterial associations may be structured by multiple factors at different scales and that corals may associate with microbes in terms of similar function, rather than identical species.
PMCID: PMC3737133  PMID: 23940737
16.  Directed Therapy for Patients with Myelodysplastic Syndromes (MDS) by Suppression of Cyclin D1 with ON 01910.Na 
Leukemia Research  2012;36(8):982-989.
We previously demonstrated upregulation of c-myc, survivin, and cyclin D1 in CD34+ bone marrow mononuclear cells (BMMNCs) of patients with trisomy 8 and monosomy 7 myelodysplastic syndromes (MDS). “Knockdown” of cyclin D1 by RNA interference decreased trisomy 8 cell growth, suggesting that this might be a therapeutic target in MDS.
Experimental Design
We performed preclinical studies using BMMNCs from patients with MDS and AML to examine the effects of the styryl sulfone ON 01910.Na on cyclin D1 accumulation, aneuploidy, and CD34+ blast percentage. We next treated twelve patients with higher risk MDS and two trisomy 8 AML patients with ON01910.Na on a phase I clinical protocol (NCT00533416).
ON 01910.Na inhibited cyclin D1 expression, and was selectively toxic to trisomy 8 cells in vitro. Flow cytometry studies demonstrated increased mature CD15+ myeloid cells and decreased CD34+ blasts. Three patients treated with ON01910.Na on a clinical had decreased bone marrow blasts by ≥50%, and three patients had hematologic improvements, one of which was sustained for 33 months. Patients with hematologic responses to ON 01910.Na had decreased cyclin D1 expression in their CD34+ cells.
The preclinical results and responses of patients on a clinical trial warrant further investigation of ON 01910.Na as a potential novel targeted therapy for higher risk MDS patients.
PMCID: PMC3381873  PMID: 22524974
MDS; Treatment; ON 01910.Na; Cyclin D1
17.  Evaluation of ALK Rearrangement in Chinese Non-Small Cell Lung Cancer Using FISH, Immunohistochemistry, and Real-Time Quantitative RT- PCR on Paraffin-Embedded Tissues 
PLoS ONE  2013;8(5):e64821.
Patients with ALK gene rearrangements often manifest dramatic responses to crizotinib, an ALK inhibitor. Accurate identification of patients with ALK-positive non-small cell lung cancer (NSCLC) is essential for the clinical application of ALK-targeted therapy. However, assessing EML4-ALK rearrangement in NSCLC remains challenging in routine pathology practice. The aim of this study was to compare the diagnostic accuracy of FISH, immunohistochemistry (IHC), and real-time quantitative RT-PCR (QPCR) methodologies for detection of EML4-ALK rearrangement in NSCLC and to appraise immunohistochemistry as a pre-screening tool. In this study, a total of 473 paraffin-embedded NSCLC samples from surgical resections and biopsies were analyzed by IHC with ALK antibody. ALK rearrangement was further confirmed by FISH and QPCR. ALK protein expression was detected in twenty patients (20/473, 4.2%). Of the 20 ALK-positive cases by IHC, 15 cases were further confirmed as ALK rearrangement by FISH, and 5 cases were not interpretable. Also, we evaluated 13 out of the 20 IHC-positive tissues by QPCR in additional to FISH, and found that 9 cases were positive and 2 cases were equivocal, whereas 2 cases were negative although they were positive by both IHC and FISH. The ALK status was concordant in 5 out of 8 cases that were interpretable by three methods. Additionally, none of the 110 IHC-negative cases with adenocarcinoma histology showed ALK rearrangements by FISH. Histologically, almost all the ALK-rearranged cases were adenocarcinoma, except that one case was sarcomatoid carcinoma. A solid signet-ring cell pattern or mucinous cribriform pattern was presented at least focally in all ALK-positive tumors. In conclusion, our findings suggested that ALK rearrangement was associated with ALK protein expression. The conventional IHC assay is a valuable tool for the pre-screening of patients with ALK rearrangement in clinical practice and a combination of FISH and QPCR is required for further confirmation.
PMCID: PMC3669339  PMID: 23741400
18.  Inhibitory Effects of Baicalin on the Expression and Activity of CYP3A Induce the Pharmacokinetic Changes of Midazolam in Rats 
Baicalin, a flavonoid compound isolated from Scutellaria baicalensis, has been shown to possess antiinflammatory, antiviral, antitumour, and immune regulatory properties. The present study evaluated the potential herb-drug interaction between baicalin and midazolam in rats. Coadministration of a single dose of baicalin (0.225, 0.45, and 0.90 g/kg, i.v.) with midazolam (10 mg/kg, i.v.) in rats resulted in a dose-dependent decrease in clearance (CL) from 25%  (P < 0.05) to 34%  (P < 0.001) with an increase in AUC0−∞ from 47%  (P < 0.05) to 53%  (P < 0.01). Pretreatment of baicalin (0.90 g/kg, i.v., once daily for 7 days) also reduced midazolam CL by 43%  (P < 0.001), with an increase in AUC0−∞ by 87%  (P < 0.01). Multiple doses of baicalin decreased the expression of hepatic CYP3A2 by approximately 58%  (P < 0.01) and reduced midazolam 1′-hydroxylation by 23%  (P < 0.001) and 4′-hydroxylation by 21%  (P < 0.01) in the liver. In addition, baicalin competitively inhibited midazolam metabolism in rat liver microsomes in a concentration-dependent manner. Our data demonstrated that baicalin induced changes in the pharmacokinetics of midazolam in rats, which might be due to its inhibition of the hydroxylation activity and expression of CYP3A in the liver.
PMCID: PMC3655607  PMID: 23710212
19.  Tat peptide-decorated gelatin-siloxane nanoparticles for delivery of CGRP transgene in treatment of cerebral vasospasm 
Gene transfer using a nanoparticle vector is a promising new approach for the safe delivery of therapeutic genes in human disease. The Tat peptide-decorated gelatin-siloxane (Tat-GS) nanoparticle has been demonstrated to be biocompatible as a vector, and to have enhanced gene transfection efficiency compared with the commercial reagent. This study investigated whether intracisternal administration of Tat-GS nanoparticles carrying the calcitonin gene-related peptide (CGRP) gene can attenuate cerebral vasospasm and improve neurological outcomes in a rat model of subarachnoid hemorrhage.
A series of gelatin-siloxane nanoparticles with controlled size and surface charge was synthesized by a two-step sol-gel process, and then modified with the Tat peptide. The efficiency of Tat-GS nanoparticle-mediated gene transfer of pLXSN-CGRP was investigated in vitro using brain capillary endothelial cells and in vivo using a double-hemorrhage rat model. For in vivo analysis, we delivered Tat-GS nanoparticles encapsulating pLXSN-CGRP intracisternally using a double-hemorrhage rat model.
In vitro, Tat-GS nanoparticles encapsulating pLXSN-CGRP showed 1.71 times higher sustained CGRP expression in endothelial cells than gelatin-siloxane nanoparticles encapsulating pLXSN-CGRP, and 6.92 times higher CGRP expression than naked pLXSN-CGRP. However, there were no significant differences in pLXSN-CGRP entrapment efficiency and cellular uptake between the Tat-GS nanoparticles and gelatin-siloxane nanoparticles. On day 7 of the in vivo experiment, the data indicated better neurological outcomes and reduced vasospasm in the subarachnoid hemorrhage group that received Tat-GS nanoparticles encapsulating pLXSN-CGRP than in the group receiving Tat-GS nanoparticles encapsulating pLXSN alone because of enhanced vasodilatory CGRP expression in cerebrospinal fluid.
Overexpression of CGRP attenuated vasospasm and improved neurological outcomes in an experimental rat model of subarachnoid hemorrhage. Tat-GS nanoparticle-mediated CGRP gene delivery could be an innovative strategy for treatment of cerebral vasospasm after subarachnoid hemorrhage.
PMCID: PMC3617792  PMID: 23576867
gene transfer; nanoparticles; calcitonin gene-related peptide; cerebral vasospasm
21.  A genetic interaction network of five genes for human polycystic kidney and liver diseases defines polycystin-1 as the central determinant of cyst formation 
Nature genetics  2011;43(7):639-647.
Autosomal dominant polycystic liver disease results from mutations in PRKCSH or SEC63. The respective gene products, glucosidase IIβ and SEC63p, function in protein translocation and quality control pathways in the endoplasmic reticulum. Here we show that glucosidase IIα and Sec63p are required in mice for adequate expression of a functional complex of the polycystic kidney disease gene products, polycystin-1 and polycystin-2. We find that polycystin-1 is the rate-limiting component of this complex and that there is a dose-response relationship between cystic dilation and levels of functional polycystin-1 following mutation of Prkcsh or Sec63. Reduced expression of polycystin-1 also serves to sensitize the kidney to cyst formation resulting from mutations in Pkhd1, the recessive polycystic kidney disease gene. Finally, we show that proteasome inhibition increases steady-state levels of polycystin-1 in cells lacking glucosidase IIβ and that treatment with a proteasome inhibitor reduces cystic disease in orthologous gene models of human autosomal dominant polycystic liver disease.
PMCID: PMC3547075  PMID: 21685914
22.  Synthesis and characterization of NIR-responsive Aurod@pNIPAAm-PEGMA nanogels as vehicles for delivery of photodynamic therapy agents 
A near-infrared (NIR)-responsive Aurod@pNIPAAm-PEGMA nanogel was synthesized in two steps, growing a PEGMA monolayer on the surface of gold nanorods (AuNRs), followed by in situ polymerization and cross-linking of N-iso-propylacrylamide (NIPAAm) and poly-(ethylene glycol)-methacrylate (PEGMA). The AuNRs and Aurod@pNIPAAm-PEGMA nanogel were characterized by UV–vis spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy, respectively. The lower critical solution temperature of the Aurod@pNIPAAm-PEGMA nanogel could be tuned by changing the molar ratio of NIPAAm/PEGMA. The NIR-mediated drug release behavior of the Aurod@pNIPAAm-PEGMA nanogel was studied with zinc phthalocyanines (ZnPc4) as a drug model. It was also demonstrated that the loaded ZnPc4 could keep the capability of generating singlet oxygen, and the in vitro study showed a great photodynamic therapy (PDT) effect on Hela cells. It thus indicated the potential of this Aurod@pNIPAAm-PEGMA nanogel for application as a drug carrier in PDT, which might make contributions to oncotherapy.
PMCID: PMC3599406  PMID: 23279853
NIR-responsive; Aurod@pNIPAAm-PEGMA nanogel; LCST; singlet oxygen; PDT
23.  Presence of Peripheral Arterial Disease Predicts Loss of Residual Renal Function in Incident CAPD Patients 
♦ Background: Accelerated cardiovascular disease (CVD), including peripheral arterial disease (PAD), is very common in patients with end-stage renal disease. Residual renal function (RRF) is a strong predictor of patient survival that is suggested to be linked to the degree of CVD. However, the relationship between PAD and decline in RRF has not previously been measured.
♦ Methods: We studied incident continuous ambulatory peritoneal dialysis patients from Peking University Third Hospital. An ankle brachial index of less than 0.9 was used to diagnose PAD. Residual renal function (RRF) was determined as the mean of 24-hour urea and creatinine clearances (glomerular filtration rate). The Cox proportional hazards model was used to identify factors predicting loss of RRF.
♦ Results: The study included 86 patients (age: 61 ± 14 years; men: 51%), 23 of whom had PAD at baseline. Mean follow-up was 19 months (median: 18 months; range: 6 – 30 months). In univariate analysis, baseline PAD, peritonitis during follow-up, inflammation (C-reactive protein), serum uric acid, Ca×P, and serum phosphate were all significantly associated with a greater-than-50% decrease in RRF during follow-up. In multivariate analysis, only baseline PAD, Ca×P, and peritonitis were independently associated with a decline in RRF.
♦ Conclusions: Our study suggests that PAD may be a clinically important marker of CVD predicting the loss of RRF. It remains to be determined whether interventions aimed at decreasing PAD may also improve renal vascular status and thus slow the rate of RRF decline.
PMCID: PMC3525373  PMID: 21532004
Ankle brachial index; end-stage renal disease; cardiovascular disease; inflammation; nutrition; atherosclerosis
24.  Root resource foraging: does it matter? 
PMCID: PMC3740241  PMID: 23964282

Results 1-25 (66)