Room temperature electrical and thermal switching CNT/hexadecane composites

A large contrast in the electrical and thermal conductivities via a first order phase transition in surface-functionalized carbon nanotube(CNT)/hexadecane composites is reported. Surface modification of the CNTs improves the electrical conductivity contrast and the stability of the composites. We demonstrate that, with these composites, the electrical conductivity changes above 10(5) times and the thermal conductivity varies up to 3 times at 18 °C.

Safety and efficacy of first-line bevacizumab combination therapy in Chinese population with advanced non-squamous NSCLC: data of subgroup analyses from MO19390 (SAiL) study

BACKGROUND

Bevacizumab is a monoclonal antibody with high antitumor activity against malignant diseases. Previous studies have demonstrated the efficacy of first-line bevacizumab combination therapy in advanced, non-squamous non-small cell lung cancer (NS-NSCLC). SAiL (MO19390), an open-label, multicenter, single-arm study, evaluated the safety and efficacy of first-line bevacizumab-based treatment in clinical practice. This report presents the results of a subgroup analysis of Chinese patients enrolled in SAiL.

METHODS

Chemo-naive Chinese patients with locally advanced, metastatic or recurrent NSCLC were randomized to receive Bev 15 mg/kg every 3 weeks plus carboplatin + paclitaxel for maximum of six cycles, followed by single-agent bevacizumab until disease progression. The primary endpoint was safety. Secondary endpoints included time to progression and overall survival.

RESULTS

The Chinese intent-to-treat (ITT) population consists of 198 Chinese patients, among whom 107 (54 %) were non-smokers and 90 (45.5 %) were female. The median cycle of bevacizumab administration was 10 and median duration of bevacizumab treatment was 29.5 weeks. Only eight cases of severe adverse events were observed in the study, which were deemed to be related to bevacizumab. The incidence of AEs over grade 3 in Chinese ITT patients was generally low (<9 %). No new safety signals were reported. Objective response rate in 195 evaluable Chinese patients was 68.8 %, including four complete responses (2.1 %). Time to disease progression (TTP) and overall survival were 8.8 and 18.5 months, respectively.

CONCLUSIONS

The safety and efficacy of first-line bevacizumab-based treatment in Chinese population with advanced NS-NSCLC are consistent with those in previous studies as well as in Asian subgroup population from SAiL study. No new safety signals were reported.

Clinical presentations and molecular basis of complement C1r deficiency in a male African-American patient with systemic lupus erythematosus

Homozygous deficiencies of early components for complement activation are among the strongest genetic risk factors for human systemic lupus erythematosus (SLE). Eleven cases of C1r deficiency are documented but this is the first report on the molecular basis of C1r deficiency. The proband is an African-American male who developed SLE at 3 months of age. He had a discoid lupus rash and diffuse proliferative glomerulonephritis. Serum complement analysis of the patient showed zero CH50 activity, undetectable C1r, and reduced levels of C1s, but highly elevated levels of complement C4, C2, and C1-inhibitor. The coding regions of the mutant C1R gene with 11 exons located at chromosome 12p13 were polymerase chain reaction (PCR)-amplified and sequenced to completion. DNA sequencing revealed a homozygous C→T mutation at nucleotide-6392 in exon 10 of the C1R gene, resulting in a nonsense mutation from Arg-380 (R380X). The patient's clinically normal mother was heterozygous for this mutation. A sequence-specific primer (SSP) PCR coupled with StuI-restriction fragment length polymorphism (RFLP) was developed to detect the novel mutation. Screening of 209 African-American SLE patients suggested that the R380X mutation is a rare causal variant. Mutations leading to early complement component deficiencies in SLE are mostly private variants with large effects.

Efficacy of a Multimodal Analgesia Protocol in Total Knee Arthroplasty: A Randomized, Controlled Trial

A total of 100 osteoarthritis patients undergoing unilateral total knee arthroplasty were randomly assigned to receive either a multimodal analgesia protocol, comprising oral celecoxib and tramadol before and after surgery and intra-articular injection of large doses of morphine, ropivacaine, adrenaline and betamethasone during surgery (trial group), or oral and intra-articular placebo (control group). All patients received patient-controlled analgesia for 48 h after surgery. Morphine consumption up to 48 h after surgery was significantly lower in the trial than in the control group. Compared with the control group, the trial group had significantly lower visual analogue scale (VAS) scores for pain at rest from 6 h to 7 days after surgery and significantly lower VAS scores during activity from 24 h to 7 days after surgery. Active straight leg raise and active 90° knee flexion were achieved sooner and range of knee movement at postoperative days 1–15 were significantly greater in the trial group. Postoperative wound healing, infection, blood pressure, heart rate, rash, respiratory depression, urinary retention and deep vein thrombosis were similar in the two groups, but nausea and vomiting were significantly less frequent in the trial group.

Familial C4B deficiency and immune complex glomerulonephritis

Homozygous complement C4B deficiency is described in a Southern European young female patient with Membranoproliferative Glomerulonephritis (MPGN) type III characterized by renal biopsies with strong complement C4 and IgG deposits. Low C4 levels were independent of clinical evolution or type of immunosuppression and were found in three other family members without renal disease or infections. HLA typing revealed that the patient has homozygous A*02, Cw*06, B*50 at the class I region, and DRB1*08 and DQB1*03 at the class II region. Genotypic and phenotypic studies demonstrated that the patient has homozygous monomodular RCCX in the HLA class III region, with single long C4A genes coding for C4A3 and complete C4B deficiency. Her father, mother, son and niece have heterozygous C4B deficiency. The patient's deceased brother had a history of Henoch-Schönlein Purpura (HSP), an immune complex-mediated proliferative glomerulonephritis. These findings challenge the putative pathophysiological roles of C4A and C4B and underscore the need to perform functional assays, C4 allotyping and genotyping on patients with persistently low serum levels of a classical pathway complement component and glomerulopathy associated with immune deposits.

Obtaining point spread function of penumbral encoding aperture with "expectation maximization" algorithm based on matched source-image pair experiment

A source penumbral image reconstruction method with linear mapping principle for geometrical optics is established. The ideal binary point spread function (PSF) can be obtained using a geometrical optics model. The system PSF with certain sharpness was obtained using a Monte Carlo (MC) model. Considering other factors besides the transportation of the x (gamma)-rays or particles (fusion neutrons) in the penumbral encoding aperture in MC model, such as the scattering background and the systematic error, the PSF from MC model "source-image pair matching" experiments with a large area standard oval shape source were processed. A method for correcting and calibrating the PSF by the expectation maximization adaptive algorithm was established and the optimized PSF with 22.30 microm sharpness was achieved. This is more consistent with the real system PSF despite the increased noise level of the two-dimensional PSF and large irregularity in the PSF profile.

A DATA-DRIVEN APPROACH TO PRIOR EXTRACTION FOR SEGMENTATION OF LEFT VENTRICLE IN CARDIAC MR IMAGES

In this paper, we propose a data-driven approach that extracts prior information for segmentation of the left ventricle in cardiac MR images of transplanted rat hearts. In our approach, probabilistic priors are generated from prominent features, i.e., corner points and scale-invariant edges, for both endo-and epi-cardium segmentation. We adopt a level set formulation that integrates probabilistic priors with intensity, texture, and edge information for segmentation. Our experimental results show that with minimal user input, representative priors are correctly extracted from the data itself, and the proposed method is effective and robust for segmentation of the left ventricle myocardium even in images with very low contrast. More importantly, it avoids inter- and intra- observer variations and makes accurate quantitative analysis of low-quality cardiac MR images possible.

A dual-colored bio-marker made of doped ZnO nanocrystals

Bio-compatible ZnO nanocrystals doped with Co, Cu and Ni cations, surface capped with two types of aminosilanes and titania are synthesized by a soft chemical process. Due to the small particle size (2-5 nm), surface functional groups and the high photoluminescence emissions at the UV and blue-violet wavelength ranges, bio-imaging on human osteosarcoma (Mg-63) cells and histiocytic lymphoma U-937 monocyte cells showed blue emission at the nucleus and bright turquoise emission at the cytoplasm simultaneously. This is the first report on dual-color bio-images labeled by one semiconductor nanocrystal colloidal solution. Bright green emission was detected on mung bean seedlings labeled by all the synthesized ZnO nanocrystals. Cytotoxicity tests showed that the aminosilanes capped nanoparticles are non-toxic. Quantum yields of the nanocrystals varied from 79% to 95%. The results showed the potential of the pure ZnO and Co-doped ZnO nanocrystals for live imaging of both human cells and plant systems.

Longitudinal tracking of recipient macrophages in a rat chronic cardiac allograft rejection model with noninvasive magnetic resonance imaging using micrometer-sized paramagnetic iron oxide particles

BACKGROUND

Long-term survival of heart transplants is hampered by chronic rejection (CR). Studies indicate the involvement of host macrophages in the development of CR; however, the precise role of these cells in CR is unclear. Thus, it is important to develop noninvasive techniques to serially monitor the movement and distribution of recipient macrophages in chronic cardiac allograft rejection in vivo.

METHODS AND RESULTS

We have employed a rat heterotopic working-heart CR model for a magnetic resonance imaging experiment. Twenty-one allograft (PVG.1U-->PVG.R8) and 9 isograft (PVG.R8-->PVG.R8) transplantations were performed. Recipient macrophages are labeled via intravenous injection of micron-sized paramagnetic iron oxide particles (0.9 microm in diameter) at a dose of 4.5 mg Fe per rat 1 day before transplantation. Serial in vivo magnetic resonance images were acquired for up to 16 weeks. The migration of labeled recipient cells in our CR model, in which cardiac CR is evident at 3 weeks and most extensive by 16 weeks after transplantation, can be assessed with the use of in vivo magnetic resonance imaging for >100 days after a single micron-sized paramagnetic iron oxide injection. The location and distribution of labeled recipient cells were confirmed with magnetic resonance microscopy and histology.

CONCLUSIONS

This approach may improve our understanding of the immune cells involved in CR and the management of heart transplantation. Moreover, this study demonstrates the feasibility of noninvasively observing individual targeted cells over long time periods by serial in vivo magnetic resonance imaging.

Impact of multi-walled carbon nanotubes on aquatic species

To understand the environmental impacts of carbon nanotubes (CNTs), the toxicity study was carried out with water-soluble multi-walled carbon nanotubes (MWCNTs) using zebrafish (Danio rerio) as a model system. Zebrafish embryos were treated with different concentrations of MWCNTs. Teratogenic effects were evaluated through changes in embryonic development after 24 hours post-fertilization (hpf), 48 hpf and 72 hpf. No observable effect concentration (NOEC) was at 40 microg/mL. Lowest effect concentration (LOEC) of MWCNTs which caused significant phenotypic defects in zebrafish embryo was 60 microg/mL. At concentration above 60 microg/mL, slimy mucus like coating was observed around the embryo. At high concentrations, MWCNTs was found to be involved in the apoptosis, delayed hatching and formation of abnormal spinal chords. Thus, the toxicity of multi-walled carbon nanotubes is concentration dependent.

Immune cells detection of the in vivo rejecting heart in USPIO-enhanced magnetic resonance imaging

Contrast-enhanced magnetic resonance imaging (MRI) is useful to study the infiltration of immune cells, in particular macrophages. Contrast agents, for example ultra-small superparamagnetic iron oxide (USPIO) particles, administered intravenously into the blood stream will be engulfed by macrophages circulating in the circulation system. When a transplanted heart rejects, macrophages and other immune cells will infiltrate the rejecting tissue. Imaged by T*2 weighted MRI, USPIO-labeled macrophages will display dark pixel intensities. Detecting the presence of USPIO particles in the images facilitates the study of heart rejection. We cast the problem of detecting the presence of USPIO-labeled myocardium in the framework of spectral graph theory, and treat our decision function as a level set function on the image. The pixels with positive level set values correspond to the presence of immune cells, and negative to the absence. When the image is modeled by a graph, the spectral analysis of the graph Laplacian provides a basis to represent the level set function. We develop from the Cheeger constant of the graph an objective functional of the level set function. The minimization of the objective leads to the optimal level set function. Experimental results suggest the feasibility of our approach in the study of rejecting hearts.

Expression of anion exchanger 2 in human gastric cancer

Anion exchanger 2 (AE2), which mediates exchange of Cl(-)/HCO3(-) across the plasma membrane, is widely expressed in body tissues. It is most abundantly expressed in stomach and is responsible for the uptake of Cl(-) ions that are destined to become HCl molecules.

AIM

To determine whether AE2 expression was altered in gastric tumors.

METHODS

We have studied AE2 expression in normal human gastric tissues (n =16) and in gastric tumors (n = 33) using immunohistochemistry and immunofluorescent labeling.

RESULTS

In normal gastric tissue positive staining was observed in gastric fundus gland, suggesting parietal cell-related expression of AE2, and AE2 expression was localized in the nuclear membrane and even in cell nuclei. For assay of cancerous gastric tissues, specimens of human gastric cancer arising from the region of the fundus (2 cases), the body (14 cases) and the antrum (17 cases) were randomly selected. Immunohistochemical staining has showed that AE2 was down-regulated in all 14 cancerous gastric body specimens, whereas staining for AE2 in cancerous antrum was less intense and had a diffuse profile.

CONCLUSIONS

The data suggest that AE2 might be associated with gastric carcinogenesis and the achlorhydria experienced by gastric cancer patients.

CCAAT/enhancer-binding protein alpha antagonizes transcriptional activity of hypoxia-inducible factor 1 alpha with direct protein-protein interaction

Hypoxia-inducible factor 1 (HIF-1), a master heterodimeric transcriptional regulator consisting of HIF-1alpha and HIF-1beta subunits for cellular response to hypoxia, plays an important role in carcinogenesis, while CCAAT/enhancer-binding protein alpha (C/EBPalpha) is proposed to act as a tumor suppressor in C/EBPalpha-expressing tissues. Previously, we reported that ectopically expressed HIF-1alpha protein interacts with and enhances transcriptional activity of C/EBPalpha, which favors leukemic cell differentiation. Here we further showed that such an interaction also occurred in their endogenously expressing state of leukemic U937 cells. Glutathione S-transferase pull-down assay proposed that the protein-protein interaction was direct, and transactivation domains of C/EBPalpha and the basic helix-loop-helix domain of HIF-1alpha were essential for such an interaction. More intriguingly, we provided the first demonstration that C/EBPalpha competed with HIF-1beta for direct binding to HIF-1alpha protein. Correspondingly, C/EBPalpha overexpression significantly inhibited the DNA-binding ability of HIF-1 and expressions of hypoxia-responsive element-driven luciferase and HIF-1-targeted genes vascular endothelial growth factor, glucose transporter-1 and phosphoglycerate kinase 1. In parallel, suppression of C/EBPalpha expression by specific small hairpin RNA increased DNA-binding ability of HIF-1 and expression of these HIF-1-targeted genes in leukemic U937 cells. These results would provide new insights for antitumor potential of C/EBPalpha protein.

Antidepressant activity of sarsasapogenin from Anemarrhena asphodeloides Bunge (Liliaceae)

The aim of this study was to investigate the effects of sarsasapogenin from Anemarrhena asphodeloides Bunge (Liliaceae) on two experimental models of depression in rats. After a two-week treatment, sarsasapogenin markedly shortened the immobility time in the forced swimming test and decreased the number of escape deficits in the learned helplessness paradigm, however, locomotor activity was not affected.

Orthotopic Abdominal Multivisceral Transplantation Without Venovenous Bypass in Pigs

BACKGROUND

Because venovenous bypass (VVB) can cause specific complications, a simplified orthotopic abdominal multivisceral transplantation (MVTX) technique without VVB in pigs has been evaluated in terms of morbidity and mortality.

MATERIALS AND METHODS

Outbred large-white pigs weighing 25 to 40 kg of random sex underwent MVTX operation. After in situ cold perfusion through the aorta and superior mesenteric vein, the multivisceral allograft was procured from the donor and tailored at the back table. The multivisceral allograft, including liver, pancreas, stomach, duodenum, and proximal 2 m of jejunum, was en bloc transplanted into recipient after resection of entire foregut and midgut; VVB was not used. We analyzed the hemodynamic change, arterial blood gas data, and fluid requirements intraoperatively.

RESULTS

Among 25 MVTXs, 19 (76%) animals survived after the operation. Without using an immunosuppressant, postoperative survival time was 2 to 146 hours. Ten recipient pigs died within 24 hours. Seven animals were lost between postoperative days 2 and 5. Two pigs survived for more than 5 days. The recipient pigs were mostly in a state of hypovolemic shock and metabolic acidosis during the reperfusion phase.

CONCLUSIONS

Despite a high morbidity and mortality, the simplified technique without VVB is feasible to successfully achieve MVTX in the pig.

In situ labeling of immune cells with iron oxide particles: an approach to detect organ rejection by cellular MRI

In vivo cell tracking by MRI can provide means to observe biological processes and monitor cell therapy directly. Immune cells, e.g., macrophages, play crucial roles in many pathophysiological processes, including organ rejection, inflammation, autoimmune diseases, cancer, atherosclerotic plaque formation, numerous neurological disorders, etc. The current gold standard for diagnosing and staging rejection after organ transplantation is biopsy, which is not only invasive, but also prone to sampling errors. Here, we report a noninvasive approach using MRI to detect graft rejection after solid organ transplantation. In addition, we present the feasibility of imaging individual macrophages in vivo by MRI in a rodent heterotopic working-heart transplantation model using a more sensitive contrast agent, the micrometer-sized paramagnetic iron oxide particle, as a methodology to detect acute cardiac rejection.

Aquapuncture therapy of repeat breeding in dairy cattle

Repeat breeders cause great economic loss in dairy herds. This study determined the efficacy of simple aquapuncture therapy (acupuncture combined with injection) to treat repeat breeders in two dairy herds (one in Hsinchu County and the other in Tainan County). Both herds had used gonadotropin-releasing hormone (GnRH) beforehand to treat the symptom but the success rate was poor--about 30%. Therefore, cows that failed to respond to GnRH were given the aquapuncture treatment. A total of 18 animals (two heifers and 16 cows) that had failed to conceive to 3-9 services were treated by aquapuncture, in which 10 ml and 5 ml of 50% glucose solution were injected at Baihui (Hundred Meetings, the depression in the center of the lumbosacral space) and Shenpeng (Kidney Shelf, the depression in the space between the lumbar vertebral transverse processes 5-6) acupoints, respectively with a 21G, 1.5-inch hypodermic needle. Both acupoints belong to the traditional acupuncture points of bovine and equine systems. Most animals showed heat within 14 days after aquapuncture and were inseminated artificially. Serum progesterone concentrations and rectal palpation were used for pregnancy diagnosis. The pregnancy rate after the treatment was 14/18 (77.7%) and 12/18 (66.6%) based on progesterone concentration and rectal palpation respectively, suggesting acupuncture as a simple and effective method to treat repeat breeders in dairy herds. However, the final result obtained from actual delivery of fetus in the experimental animals was only 8/18 (44.4%).

Regulation of progesterone and prostaglandin F2alpha production in the CL

After the luteinizing hormone (LH) surge, the cells that remain from the ovulated follicle undergo a process of differentiation termed luteinization. Two key features of the cells after luteinization are the capacity for tremendous production of progesterone [10(16) molecules of progesterone per (min/(g of CL))] and the capacity to undergo regression or death of the cells at the appropriate time. There are two steroidogenic cell types, the small and large luteal cells that are regulated by different mechanisms. In small luteal cells, production of progesterone is stimulated by LH through the protein kinase A (PKA) pathway. The large luteal cells of ruminants produce large quantities of progesterone that is independent of LH stimulation. Although luteotrophins clearly regulate luteal function, much of luteal progesterone production in some species appears to be constitutive, consistent with the autonomous aspects of the large luteal cell. The key regulated step in luteal progesterone production appears to be regulation of transport of cholesterol to the inner mitochondrial membrane apparently mediated by the steroidogenic acute regulatory protein (StAR). In addition, our recent research indicates that PKA is tonically active in large luteal cells and this may be responsible for the high, relatively autonomous nature of luteal progesterone production. Regression of the corpus luteum (CL) in many species is initiated by prostaglandin (PG) F2alpha secreted from the uterus. Luteal cells also have the capacity for production of PGF2alpha. Luteal PGF2alpha production can be regulated by a variety of substances including inhibition by progesterone and stimulation by cytokines. We have also characterized a positive feedback pathway in ruminant and porcine CL in which small amounts of uterine PGF(2alpha) stimulate intraluteal production of PGF2alpha due to induction of the cycloxygenase-2 (Cox-2) enzyme in large luteal cells. This positive feedback pathway is only present in CL that has acquired the capacity for luteal regression ( approximately day 7 in cow, approximately day 13 in pig). Regulation by protein kinase C (PKC) of transcriptional factors interacting with an E-box in the 5' flanking region of the Cox-2 gene is the critical regulatory element involved in this positive feedback pathway. Thus, luteinization in some species appears to change specific gene transcription such that progesterone production becomes relatively independent of acute luteotrophic regulation and intraluteal PGF2alpha synthesis is induced by the second messenger pathways that are activated by PGF2alpha.

Heterozygosity for the neurofibromatosis 1 (NF1) tumor suppressor results in abnormalities in cell attachment, spreading and motility in astrocytes

Individuals with the neurofibromatosis 1 (NF1) tumor predisposition syndrome develop low-grade pilocytic astrocytomas at an increased frequency. Previously, we demonstrated that astrocytes from mice heterozygous for a targeted mutation in the Nf1 gene (Nf1+/- astrocytes) exhibit a cell autonomous growth advantage associated with increased RAS pathway activation. In this report, we extend our initial characterization of the effect of reduced Nf1 gene expression on astrocyte function by demonstrating that Nf1+/- astrocytes exhibit decreased cell attachment, actin cytoskeletal abnormalities during the initial phases of cell spreading, and increased cell motility. Whereas these cytoskeletal abnormalities were also observed in Nf1-/- astrocytes, astrocytes expressing a constitutively active RAS molecule showed increased cell motility and abnormal actin cytoskeleton organization during cell spreading, but exhibited normal cell attachment. Based on ongoing gene expression profiling experiments on human astrocytoma tumors, we demonstrate increased expression of two proteins implicated in cell attachment, spreading and motility (GAP43 and T-cadherin) in Nf1+/- and Nf1-/- astrocytes. These results support the emerging notion that tumor suppressor gene heterozygosity results in abnormalities in cell function that may contribute to the pathogenesis of non-tumor phenotypes in NF1.