Temperature-sensitive poly(N-isopropylacrylamide-co-butyl methylacrylate) nanogel as an embolic agent: distribution, durability of vascular occlusion, and inflammatory reactions in the renal artery of rabbits

BACKGROUND AND PURPOSE

We have developed a new thermosensitive liquid embolic agent, PIB nanogel, that can be solidified at body temperature. We thus further investigated the distribution, durability of vascular occlusion, and inflammatory reactions of PIB in embolization of the renal artery of rabbits.

MATERIALS AND METHODS

The bilateral renal arteries of 9 rabbits were first embolized with PIB at different injection rates. The distribution pattern of PIB was investigated by contact radiography and histology 1 hour after embolization. The right renal arteries of 20 rabbits were then embolized with PIB at the proper injection rate. Angiography and pathologic examination of the kidneys were performed at 1 week and 1, 2, and 3 months after embolization to evaluate the long-term outcomes.

RESULTS

With the injection rate increasing, PIB could reach the more distal branch of the renal artery. The proper injection rate was chosen as 0.10 mL/s due to the homogeneous distribution of PIB from the main renal artery to the precapillary level at this rate. During a 3-month follow-up observation period, no angiographic recanalization was observed. Histologically, we found no disruption of the vessel wall or subintimal bleeding, no extravasation of PIB, and no evidence of neovascularization. Moreover, there was only a mild inflammatory response, manifested by few lymphocytic and monocellular infiltration, without foreign body granuloma formation.

CONCLUSIONS

Embolization of the renal artery with PIB was easy and controllable, which could lead to a homogeneous and persistent occlusion without severe inflammatory changes. PIB might be a suitable material for intravascular embolization.

Abstract P1-07-12: Using Natural Language Processing to Identify and Extract HER2 Value from a large EMR system

Background: HER2 status is important in breast cancer prognosis but has not been well collected in NCI-SEER affiliated cancer registries until recent years. For example, in a cohort of 2,846 women who were diagnosed with breast cancer from 1997 to 2011 in a large health plan, only 49% of these patients had known HER2 status. However, many of these with missing HER2 status were documented in clinical notes. This study used Natural Language Processing (NLP) technology to identify and extract HER2 status. NLP results were validated by comparison with cancer registry data and any discrepancies were manually reviewed.

Method: We assembled a cohort of 2,846 breast cancer patients from the membership of a health plan based in southern California, Kaiser Permanente. All free text notes including pathology reports, progress notes, and discharge summaries were extracted from our electronic medical record (EMR) system. A window of 9 months before and after the diagnosis date was applied to restrict the number of notes needed to be processed. Overall, 513,903 clinical notes were processed and indexed, which averages to 180 notes per patient. Separate ontologies were created for the HER2 terminology and HER2 status. HER2 status values included positive, negative, borderline, test performed and test not performed. The NLP system employed additional components such as spelling correction, acronym recognition and negation identification. The output from the NLP system was further processed in three steps: Identification of the HER2 concept, followed by extraction of the most likely HER2 value, and lastly, a decision module to select the most likely HER2 value if there were conflicting values.

Results: Use the cancer registry data as the gold standard, for positive and negative HER2 values, the sensitivity and specificity of the NLP algorithm were 94.7% and 93.3%, respectively, including the cases where NLP did not select either positive or negative values. A manual chart review was performed on the discrepant cases. We found that the NLP were correct for many of these cases. For example, out of the 39 NLP positive but registry negative cases, 4 were false positives and 35 were true positives. Compared to the cancer registry data, NLP increased capture of positive and negative HER2 cases from 49% to 73% of the cohort population.

Discussion: NLP provides the opportunity to process clinical notes which are added to the EMR after the cancer registry has completed documenting the patients' initial course of cancer treatment. On the other hand, NLP was not able to access some of the HER2 related clinical notes. For example, according to our chart review, some notes were stored as scanned images and not retrievable. In addition, clinical notes with incorrect filing dates so patients without any diagnosis date were not processed. We also identified key challenges in determining HER2 results using NLP in this study. First, non-standard terminology for the HER2 receptor in the clinical notes hampered the NLP effectiveness. Second, clinicians described HER2 results in many different ways.

Intravascular parasympathetic cardiac nerve stimulation prevents ventricular arrhythmias during acute myocardial ischemia

Although previous animal studies clearly demonstrated antiarrhythmic effects of vagal stimulation during acute myocardial ischemia, highly invasive nature of vagal stimulation limited its clinical use. Recently, intravascular parasympathetic cardiac nerve stimulation (IPS) has emerged as a novel approach to the cardiac autonomic nervous system. We hypothesized that IPS might prevent ventricular arrhythmias during acute myocardial ischemia.

METHODS

The IPS (36 V, 10 Hz) was performed in superior vena cava using an expandable electrode-basket catheter. In 18 open-chest dogs, left anterior descending coronary artery ligation was performed without IPS (control group, n= 6), with IPS (IPS group, n= 6) and with IPS and right atrial pacing at 180/min (IPS+P group, n=6). The ECGs were monitored for 60 min. The incidence and severity of ventricular arrhythmias were analyzed.

RESULTS

The IPS significantly decreased the frequency of premature ventricular contractions (control group: 9.1 &#177; 4.6/min, IPS group: 0.2 &#177; 0.4 /min, IPS+P group: 10.6 &#177; 4.2 / min; p&lt;0.05). The frequency of ventricular tachycardia was lower in IPS group (0 &#177; 0 /min) than in control group (0.15 &#177; 0.18 /min, p&lt;0.05) and than in IPS+P group (0.17 &#177; 0.12 /min, p<0.05). The incidence of ventricular fibrillation was lower in IPS group (0%) than in control group (33.3%) and than in IPS+P group (33.3%).

CONCLUSIONS

The IPS suppressed ventricular arrhythmias during acute ischemia mainly through its bradycardiac effect.

Characterization and emulsifying property of a novel bioemulsifier by Aeribacillus pallidus YM-1

AIMS

  Biosurfactants and bioemulsifiers commonly have the advantages of biodegradability, low toxicity, selectivity and biocompatibility over chemically synthesized surfactants. The goal of the study is to present a novel bioemulsifier with great application potential.

METHODS AND RESULTS

  Aeribacillus pallidus YM-1, isolated from crude oil contaminated soil, was found to produce a novel high molecular bioemulsifier with an emulsification index of 60 ± 1% without remarkable surface tension reduction (45·7 ± 0·1 mN m(-1) ). The number-average molecular weight was determined as 526 369 Da by gel permeation chromatography analysis. Bioemulsifier was subjected to FT-IR and a complex of carbohydrates (41·1%), lipids (47·6%) and proteins (11·3%) was determined.

CONCLUSIONS

  The bioemulsifier of A. pallidus YM-1 was isolated from the glucose-based culture medium and characterized with the help of chemical analytical techniques. The bioemulsifier exhibited a promising emulsifying property for biotechnology application potential in bioremediation and microbial enhanced oil recovery.

SIGNIFICANCE AND IMPACT OF THE STUDY

  This is the first report of the bioemulsifier production by A. pallidus. The potential emulsifying activity of the bioemulsifier in the present study may be explored in various biotechnological and industrial applications.

Inferring coancestry in population samples in the presence of linkage disequilibrium

In both pedigree linkage studies and in population-based association studies there has been much interest in the use of modern dense genetic marker data to infer segments of gene identity by descent (ibd) among individuals not known to be related, to increase power and resolution in localizing genes affecting complex traits. In this article, we present a hidden Markov model (HMM) for ibd among a set of chromosomes and describe methods and software for inference of ibd among the four chromosomes of pairs of individuals, using either phased (haplotypic) or unphased (genotypic) data. The model allows for missing data and typing error, but does not model linkage disequilibrium (LD), because fitting an accurate LD model requires large samples from well-studied populations. However, LD remains a major confounding factor, since LD is itself a reflection of coancestry at the population level. To study the impact of LD, we have developed a novel simulation approach to generate realistic dense marker data for the same set of markers but at varying levels of LD. Using this approach, we present results of a study of the impact of LD on the sensitivity and specificity of our HMM model in estimating segments of ibd among sets of four chromosomes and between genotype pairs. We show that, despite not incorporating LD, our model has been quite successful in detecting segments as small as 10(6) bp (1 Mpb); we present also comparisons with fastIBD which uses an LD model in estimating ibd.

Difference in pre- and postchemotherapy vascular endothelial growth factor levels as a prognostic indicator in osteosarcoma

This retrospective analysis examined the difference in pre- and postchemotherapy levels of vascular endothelial growth factor (VEGF) as an indicator of osteosarcoma prognosis. VEGF protein levels were assessed immunohistochemically in primary tumour samples from 61 osteosarcoma patients diagnosed between February 2001 and July 2005. The difference in pre- and postchemotherapy VEGF protein reduction levels was categorized into weak (23 patients) and strong (38 patients). The 5-year survival rate was significantly lower in the weak VEGF reduction group (34.8%) than in the strong VEGF reduction group (73.7%). The weak VEGF reduction group had significantly higher rates of metastasis and recurrence. Multivariate analysis confirmed that the change in VEGF was an independent and significant factor for predicting a good prognosis. The analysis of VEGF will enable clinicians to tailor surgery and chemotherapy regimens more appropriately, earlier in the disease process.

Including the p53 ELAV-like protein-binding site in vector cassettes enhances transgene expression in rat submandibular gland

OBJECTIVE

ELAV-like proteins regulate mRNA stability and/or translation. We evaluated whether inclusion of binding sites for ELAV-like HuR proteins in vector cassettes could improve transgene expression in the salivary gland.

METHODS

Western blots and immunofluorescence staining were used to determine whether HuR protein was expressed in salivary cells and tissue. HuR binding sites were inserted into the pACEF1α-luc-BGH expression plasmid. Cell lines were transfected with plasmids in vitro and luciferase expression measured. Rat submandibular glands were transfected in vivo with plasmids containing ELAV-like HuR protein-binding sites. An adenoviral vector with p53 ELAV-like HuR protein-binding site was generated and also tested in vivo. Four unique 29mer HuR shRNA constructs were used in A5 cells to evaluate whether there was a specific interaction between HuR protein and the p53 HuR protein-binding site.

RESULTS

Salivary cells express HuR protein. Inclusion of the p53 ELAV-like HuR protein-binding site resulted in high luciferase activity in salivary cells in vitro, with similar results in vivo. In vitro shRNA data demonstrated that the high luciferase activity was mediated by the interaction between HuR protein and the p53 HuR protein-binding site. The AdEF1α-luc-p53BGH, including this binding site, mediated very high luciferase activity, ~4-fold that seen with the CMV promoter, in rat submandibular glands.

CONCLUSIONS

Including the p53 ELAV-like protein-binding site in transgene cassettes may enhance therapeutic vectors intended for use with salivary glands.

Differential expression and adherence of Porphyromonas gingivalis FimA genotypes

Porphyromonas gingivalis is a primary pathogen involved in the initiation and progression of adult chronic periodontitis. Its colonization on oral surfaces is a necessary first step leading to infection. FimA, a subunit protein of major (long) fimbriae, is a well-known virulence factor. Based on its nucleotide sequence, FimA is classified into several genotypes. We compared here the transcriptional levels of the fimA gene in several P. gingivalis strains using real-time polymerase chain reaction analysis, fimbrial display on the P. gingivalis surface using transmission electronic microscopy, and the adherence competencies of P. gingivalis strains carrying different types of FimAs towards saliva and Streptococcus gordonii surfaces using mutagenesis analysis. We demonstrated differential expression of each fimA gene in these P. gingivalis strains. A correlation of the transcription level of fimA and binding activity of P. gingivalis was revealed. We show that P. gingivalis strains with genotype I and II of FimA are efficient in interaction with saliva or S. gordonii. This work highlights the important role of FimA type I and II in P. gingivalis attachment to oral surfaces.

Abashian-Booth-Crowe effect in basic double-pionic fusion: a new resonance?

We report on an exclusive and kinematically complete high-statistics measurement of the basic double-pionic fusion reaction pn→dπ(0)π(0) over the full energy region of the ABC effect, a pronounced low-mass enhancement in the ππ-invariant mass spectrum. The measurements, which cover also the transition region to the conventional t-channel ΔΔ process, were performed with the upgraded WASA detector setup at COSY. The data reveal the Abashian-Booth-Crowe effect to be uniquely correlated with a Lorentzian energy dependence in the integral cross section. The observables are consistent with a narrow resonance with m=2.37  GeV, Γ≈70  MeV and I(J(P))=0(3(+)) in both pn and ΔΔ systems. Necessary further tests of the resonance interpretation are discussed.

Convenient and reproducible in vivo gene transfer to mouse parotid glands

OBJECTIVES

Published studies of gene transfer to mouse salivary glands have not employed the parotid glands. Parotid glands are the likely target tissue for most clinical applications of salivary gene transfer. The purpose of the present study was to develop a convenient and reproducible method of retroductal gene transfer to mouse parotid glands.

METHODS

The volume for vector delivery was assessed by infusion of Toluidine Blue into Stensen's ducts of Balb/c mice after direct intraoral cannulation. Recombinant, serotype 5 adenoviral vectors, encoding either firefly luciferase or human erythropoietin (hEpo), were constructed and then administered to parotid glands (10(7) vector particles/gland). Transgene expression in vivo was measured by enzyme activity (luciferase) or an enzyme-linked immunosorbent assay (hEpo). Vector biodistribution was measured by real-time quantitative (Q) PCR.

RESULTS

The chosen volume for mouse parotid vector delivery was 20μL. Little vector was detected outside of the targeted glands, with both QPCR and luciferase assays. Transgene expression was readily detected in glands (luciferase, hEpo), and serum and saliva (hEpo). Most secreted hEpo was detected in saliva.

CONCLUSION

These studies show that mouse parotid glands can be conveniently and reproducibly targeted for gene transfer, and should be useful for pre-clinical studies with many murine disease models.

Human parathyroid hormone is secreted primarily into the bloodstream after rat parotid gland gene transfer

Hypoparathyroidism is a hormone deficiency syndrome that leads to low blood calcium levels and for which current replacement therapy is inadequate. Gene transfer to salivary glands leads to safe and abundant secretion of therapeutic protein into either saliva or the bloodstream. We previously reported the successful transduction of rat submandibular glands with an adenoviral vector encoding human parathyroid hormone (Ad.hPTH), but unfortunately most of the hPTH was secreted into saliva. Because submandibular and parotid glands are morphologically and functionally different, we hypothesized that hPTH sorting might be different in parotid glands. After 2 days, the pattern of hPTH secretion from transduced parotid glands of intact rats was reversed from that of transduced submandibular glands, that is, most transgenic hPTH was detected in serum (5 × 10(10) viral particles per gland; the saliva-to-serum ratio of total hPTH secreted was 0.04). Vector copies were localized to the targeted parotid glands, with none detected in liver or spleen. Ad.hPTH next was administered to parotid glands of parathyroidectomized rats. Two days after delivery no hPTH was detectable in saliva, but high levels were found in serum, leading to normalization of serum calcium and a significant increase in the urinary phosphorus-to-creatinine ratio. This study demonstrates for the first time differential sorting of transgenic hPTH between submandibular and parotid glands, suggesting that hPTH may be a valuable model protein for understanding the molecular basis of transgenic secretory protein sorting in these exocrine glands. We also show the clinical potential of salivary gland hPTH gene therapy for patients with hypoparathyroidism.

Transgenic α-1-antitrypsin secreted into the bloodstream from salivary glands is biologically active

OBJECTIVES

Salivary glands are potentially a valuable target for gene therapeutics. Herein, we examined the expression and biochemical activity of human alpha-1-antitrypsin (hA1AT) produced in rodent submandibular glands after gene transfer.

METHODS

A serotype 5 adenoviral vector (Ad.hA1AT) was constructed and first characterized by dose response and time course studies using SMIE cells in vitro. hA1AT expression was analysed by ELISA and the biologic activity determined by the inhibition of human neutrophil elastase (hNE) and formation of hA1AT-hNE complexes. Ad.hA1AT was administered to submandibular glands of rats and mice. The levels and activity of hA1AT were analysed in saliva, serum and gland extracts. Treatment with endoglycosidase H and Peptide N-Glycosidase F was used to assess N-linked glycosylation.

RESULTS

Transgenic hA1AT, expressed in submandibular glands following Ad.hA1AT administration, was secreted into the bloodstream, N-glycosylated and biochemically active.

CONCLUSION

After in vivo gene transfer, rodent salivary glands can produce a non-hormonal, transgenic, secretory glycoprotein exhibiting complex and conformation-dependent biologic activity.

Intravenous administration of bone marrow mesenchymal stem cells benefits experimental autoimmune myasthenia gravis mice through an immunomodulatory action

Mesenchymal stem cells (MSC) are potent in immunomodulation. It has been proven that MSC functioned to correct immune disorder in several immune diseases. Here, we tested the hypothesis that MSC from human bone marrow (hMSC) can provide a potential therapy for experimental autoimmune myasthenia gravis (EAMG). EAMG mice model was established by subcutaneous injection of synthetic analogue of acetylcholine receptor (AchR), then, hMSC were intravenously delivered into these mice repeatedly. The results showed that hMSC could specifically home to spleen tissue and hMSC treatment significantly improved the functional deficits of EAMG mice. In addition, AchR antibody level was dramatically decreased in cell-treated group when compared with untreated control on 10 days after the second cell injection. Moreover, both in vivo and in vitro mixed lymphocyte proliferation assays revealed that hMSC could definitely inhibit the proliferation of AchR-specific lymphocyte. In conclusion, our study demonstrated that hMSC treatment was therapeutically useful in autoimmune myasthenia gravis mice, and the underlying mechanism may relate with their immunomodulatory potential.

Evaluation of a rapamycin-regulated serotype 2 adeno-associated viral vector in macaque parotid glands

OBJECTIVES

Salivary glands are useful target organs for local and systemic gene therapeutics. For such applications, the regulation of transgene expression is important. Previous studies by us in murine submandibular glands showed that a rapamycin transcriptional regulation system in a single serotype 2, adeno-associated viral (AAV2) vector was effective for this purpose. This study evaluated if such a vector was similarly useful in rhesus macaque parotid glands.

METHODS

A recombinant AAV2 vector (AAV-TF-RhEpo-2.3w), encoding rhesus erythropoietin (RhEpo) and a rapamycin-inducible promoter, was constructed. The vector was administered to macaques at either of two doses [1.5 x 10(11) (low dose) or 1.5 x 10(12) (high dose) vector genomes] via cannulation of Stensen's duct. Animals were followed up for 12-14 weeks and treated at intervals with rapamycin (0.1 or 0.5 mg kg(-1)) to induce gene expression. Serum chemistry, hematology, and RhEpo levels were measured at interval.

RESULTS

AAV-TF-RhEpo-2.3w administration led to low levels of rapamycin-inducible RhEpo expression in the serum of most macaques. In five animals, no significant changes were seen in serum chemistry and hematology values over the study. One macaque, however, developed pneumonia, became anemic and subsequently required euthanasia. After the onset of anemia, a single administration of rapamycin led to significant RhEpo production in this animal.

CONCLUSION

Administration of AAV-TF-RhEpo-2.3w to macaque parotid glands was generally safe, but led only to low levels of serum RhEpo in healthy animals following rapamycin treatment.

Quantum simulation of nuclear rearrangement in electron transfer reactions

A quantum simulation scheme based on the path integral molecular dynamics technique has been used to calculate the effective activation energies associated with nuclear rearrangement in the electron transfer reactions Co(NH(3))(6) (2+) + Co(NH(3))(6) (3+) --> Co(NH(3))(6) (3+) + Co(NH(3))(6) (2+) and Ru(NH(3))(6) (2+) + Ru(NH(3))(6) (3+) --> Ru(NH(3))(6) (3+) + Ru(NH(3))(6) (2+). Even with a simple Hamiltonian and short time dynamic simulations, the results are in satisfactory agreement with other theoretical calculations. This simulation approach can be used in chemical and biological systems where the reactions are largely controlled by nuclear rearrangements, such as those of electron transfer reactions in some electron carrier proteins.