Gold nanoparticles as a contrast agent for in vivo tumor imaging with photoacoustic tomography

Photoacoustic tomography (PAT) is a rapidly emerging non-invasive imaging technology that integrates the merits of high optical contrast with high ultrasound resolution. The ability to quantitatively and non-invasively image nanoparticles has important implications for the development of nanoparticles as in vivo cancer diagnostic and therapeutic agents. In this study, the ability of systemically administered poly(ethylene glycol)-coated (PEGylated) gold nanoparticles as a contrast agent for in vivo tumor imaging with PAT has been evaluated. We demonstrate that gold nanoparticles (20 and 50 nm) have high photoacoustic contrast as compared to mouse tissue ex vivo. Gold nanoparticles can be visualized in mice in vivo following subcutaneous administration using PAT. Following intravenous administration of PEGylated gold nanoparticles to tumor-bearing mice, accumulation of gold nanoparticles in tumors can be effectively imaged with PAT. With gold nanoparticles as a contrast agent, PAT has important potential applications in the image guided therapy of superficial tumors such as breast cancer, melanoma and Merkel cell carcinoma.

SHARP-2 gene silencing by lentiviral-based short hairpin RNA interference prolonged rat kidney transplant recipients' survival time

Split- and hairy-related protein-2 (SHARP-2) controls the expression of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma), which both play a key role in transplant rejection. This study was designed to investigate whether SHARP-2 short hairpin RNA interference (shRNAi) could prolong the survival of rat kidney transplant recipients. A lentiviral-based shRNAi construct, LV-SHARP-2iC, showed a SHARP-2 gene silencing efficiency of 84% in normal rat kidney cells. In activated T-cells, SHARP-2 gene silencing with the LV-SHARP-2iC construct resulted in 61% and 69% down-regulation of IL-2 and IFN-gamma, respectively, compared with a scramble control construct. When donor kidney was perfused with 5 x 10(7) transforming units of the LV-SHARP-2iC construct, the median survival time of the transplant recipients was prolonged by 4 - 5 days compared with control groups. In conclusion, recombinant lentiviral LV-SHARP-2iC construct effectively silenced SHARP-2 gene expression, which reduced IL-2 and IFN-gamma mRNA expression and prolonged rat kidney transplant recipients' survival.

Screening for fractions of Oxytropis falcata Bunge with antibacterial activity

Preliminary studies with the four extracts of Oxytropis falcate Bunge exhibited that the chloroform and ethyl acetate extracts showed stronger antibacterial activities against the nine tested Gram-positive and Gram-negative bacteria. The HPLC-scanned and bioassay-guided fractionation led to the isolation and identification of the main flavonoid compounds, i.e. rhamnocitrin, kaempferol, rhamnetin, 2',4'-dihydroxychalcone and 2',4',beta-trihydroxy-dihydrochalcon. Except 2',4',beta-trihydroxy-dihydrochalcon, four other compounds had good antibacterial activities. The minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of the four compounds ranged between 125 and 515 microg mL(-1). Staphylococcus aureus was the most susceptible to these compounds, with MIC and MBC values from 125 to 130 microg mL(-1). This is the first report of antibacterial activity in O. falcate Bunge. In this study, evidence to evaluate the biological functions of O. falcate Bunge is provided, which promote the rational use of this herb.

Rapid and specific detection of H3 swine influenza virus using reverse transcription loop-mediated isothermal amplification method

AIM

The main objective of our study is to develop a reverse transcriptase loop-mediated isothermal amplification (RT-LAMP)-based system for rapid and specific detection of H3 swine influenza virus (SIV).

METHODS AND RESULTS

The system, H3 RT-LAMP, contained a set of six novel primers that targeted eight distinct regions of the viral haemagglutinin (HA) gene that are highly conserved among H3 influenza A viruses but not between H3 and other subtypes. H3 RT-LAMP accurately and specifically detected H3 SIV of different isolates from culture and from swine lung samples. The system is at least 10-fold more sensitive than the conventional RT-PCR assay and even comparable to the real-time RT-PCR method, with the detection limit of about one plaque-forming unit per reaction. Of 27 swine lung samples tested, 11 samples were positive in reactions with the RT-LAMP and real-time RT-PCR methods, while only 7 were positive with the conventional RT-PCR assay. Importantly, the assay can be completed within 45 min and is faster than the conventional RT-PCR and real-time RT-PCR approaches.

CONCLUSIONS

Our results provide the first direct evidence that RT-LAMP is highly specific and sensitive for detecting H3 SIV.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results suggest that LAMP offers a promising alternative tool for rapid, inexpensive and specific diagnosis of influenza virus infection of swine and other animals in frontline settings.

A miniature condition in Brahman cattle is associated with a single nucleotide mutation within the growth hormone gene

Miniature Brahman cattle at the USDA ARS Subtropical Agriculture Research Station in Brooksville, FL have normal proportioned growth but are approximately 70% of mature height and weight when compared with Brahman cattle in the same herd. Pedigree analyses suggest that the condition is inherited through a recessive allele. The miniature Brahman cattle in the Brooksville herd have been used for studies of growth and reproduction, but the underlying causative mutation is unknown. Presumably, the miniature condition could arise from a mutation in the GH gene. The objective, therefore, was to clone the GH cDNA from Brooksville miniature Brahman cattle, compare its sequence to normal Brahman cattle, and test the biological activity of the native GH protein. Messenger RNA was isolated from the pituitary, and a cDNA for the protein coding region of the GH gene was amplified by reverse-transcription polymerase chain reaction (PCR) from each of 2 miniature Brahman bulls. The cDNA were cloned into plasmid vectors, and top and bottom strands were sequenced by automated DNA sequencing. The sequence of both cDNA clones derived from miniature cattle differed from Bos indicus GH (GenBank AF034386) at base number 641 because there was a cytosine (C) instead of a thymine (T). The C to T change encoded a mutation (threonine to methionine) at amino acid 200 (T200M mutation). The mutation was confirmed by sequencing of an additional 2 miniature cattle and comparing their sequence to 2 normal cattle. The threonine is located in the fourth alpha helix of GH and is 1 of 8 amino acids that participate in binding of GH to the GH receptor. Twelve miniature Brahman and 9 normal Brahman cattle were tested by using a restriction fragment length polymorphism analysis that employed the BsmBI restriction enzyme (specific for the mutated nucleotide). The 12 miniature Brahman cattle were homozygous for the mutation (-/-). Seven of the normal Brahman cattle were homozygous for the wild-type allele (+/+), and 2 were heterozygous (+/-). When tested in a cell-based bioassay, GH isolated from the pituitary of -/- cattle (n=4) had approximately 60% activity when compared with GH isolated from the pituitary of +/+ cattle (n=5). In summary, miniature Brahman cattle were homozygous for a single nucleotide polymorphism that encodes a mutation in an amino acid involved in binding of GH to the GH receptor. Cattle of normal size had at least 1 copy of the normal GH allele. Threonine 200 in bovine GH is required for normal growth in cattle.

Kidney transplantation from hepatitis B surface antigen positive donors into hepatitis B surface antibody positive recipients: a prospective nonrandomized controlled study from a single center

The number of patients on renal transplant waiting list is increasing rapidly in many countries, exacerbating the shortage of organs. We conducted a study to evaluate the safety and efficacy of deceased-donor kidney transplantation from hepatitis B surface antigen (HBsAg)-positive (+) donors into hepatitis B surface antibody (anti-HBs)-positive (+) recipients. Sixty-five patients received grafts from HBsAg(+) donors, and 308 subjects received grafts from HBsAg-negative(-) donors. Posttransplantation, recipients with HBsAg(-) grafts or HBsAg(+) grafts received 400 U of hepatitis B immunoglobulin once and twice, respectively. The seven recipients who received grafts from hepatitis B virus (HBV) DNA(+) donors were treated with hepatitis B immunoglobulin 400 U weekly for 3 months and lamivudine 100 mg daily for 6 months. All patients were monitored for liver function and hepatitis B viral status. The follow-up period was 38.7 +/- 15.4 months. Although two recipients developed de novo HBV infection, neither patient developed severe liver dysfunction nor died. The incidence of liver injury (39/65 vs. 207/308, chi-square test, p > 0.05) and survival (log-rank test, p > 0.05) did not differ between the groups. We conclude that anti-HBs(+) recipients receiving HBsAg(+) grafts did as well as those receiving HBsAg(-) grafts.

Transformations in wrinkle patterns: cooperation between nanoscale cross-linked surface layers and the submicrometer bulk in wafer-spun, plasma-treated polydimethylsiloxane

We demonstrate control of the topography of strain-induced wrinkle patterns through the interplay between the bulk and the nanoscale cross-linked top layer of plasma treated, spin-coated polydimethylsiloxane (PDMS) thin films. The different morphological phases observed, varying from herringbones to caps, are in agreement with recent theoretical predictions. The cap phase exhibits short-range 3-fold-symmetric close-packed self-organization, demonstrating a bottom-up pathway toward the wafer-scale production of ordered, nanoscale patterns on surfaces.

Growth hormone stimulation of serum insulin concentration in cattle: nutritional dependency and potential mechanisms

Previous studies on the effect of growth hormone (GH) on serum insulin concentration in cattle had generated seemingly conflicting results, and little was known about the mechanism by which GH affects serum insulin concentration in cattle, if it does. In this study, we determined whether the effect of GH on serum insulin concentration in cattle could be affected by the nutritional levels of the animal and whether GH increased serum insulin concentration in cattle by directly stimulating insulin release or insulin gene expression in the pancreatic islets. Administration of recombinant bovine GH increased serum insulin concentration in nonlactating, nonpregnant beef cows fed a daily concentrate meal in addition to ad libitum hay, but it had no effect in those cows fed hay only. Both GH treatments for 1 and 24h increased insulin concentrations in cultures of pancreatic islets isolated from growing cattle. Growth hormone treatment for 24h increased insulin mRNA expression in cultured bovine pancreatic islets. Growth hormone treatment for 16h increased reporter gene expression directed by a approximately 1,500-bp bovine insulin gene promoter in a rat insulin-producing beta cell line. Taken together, these results suggest that exogenous GH can increase serum insulin concentration in cattle, but this effect depends on the nutritional levels of fed cattle, and that GH increases serum insulin concentration in cattle by stimulating both insulin release and insulin gene expression in the pancreatic islets.

Identification and characterization of the bovine G protein-coupled receptor GPR41 and GPR43 genes

Volatile fatty acids (VFA), including acetate, propionate, and butyrate, are not only a primary source of energy, but also regulate rumen development, insulin and glucagon secretion, and other physiological processes in cattle and sheep. The mechanism underlying the regulatory effects of VFA is unknown. Recent "reverse pharmacology" studies identified human G protein-coupled receptors GPR41 and GPR43 as receptors for short-chain fatty acids. It is possible that proteins similar to human GPR41 and GPR43 mediate the regulatory effects of VFA in cattle. In this study, we determined first, whether the bovine genome contains genes similar to the human GPR41 and GPR43 genes; second, whether and where these genes are expressed in cattle; and third, if the proteins encoded by these genes can be activated by acetate, propionate, and butyrate. A search of GenBank revealed bovine genomic sequences and expressed sequence tags highly similar to the human GPR41 and GPR43 DNA and cDNA sequences. The protein-coding and 5' untranslated regions of the bovine GPR41 and GPR43 mRNA were cloned and sequenced from spleen tissue. Based on these sequences, the bovine GPR41 gene contains 3 exons and its transcription is initiated at 2 leader exons, generating 2 GPR41 mRNA variants differing in the 5' untranslated region. The bovine GPR43 gene contains 2 exons and transcription of this gene is initiated from a single start site. The amino acid sequences deduced from the bovine GPR41 and GPR43 mRNA sequences are more than 75% identical to those of the human GPR41 and GPR43 and are predicted to encode 7 transmembrane domains, typical of G protein-coupled receptors. Both bovine GPR41 and GPR43 mRNA were detected in a variety of tissues including rumen and pancreas. In a cell system, interaction of the overexpressed bovine GPR41 or GPR43 protein with acetate, propionate, or butyrate inhibited luciferase reporter expression from a cyclic AMP-responsive promoter, suggesting that the bovine GPR41 and GPR43 proteins couple to Galpha(i/11). In total, these results demonstrate that the bovine genome encodes functional GPR41 and GPR43 genes and suggest that GPR41 and GPR43 may play a role in the regulatory effects of VFA in cattle.

Methamphetamine Dysregulates Redox Status in Primary Rat Astrocyte and Mesencephalic Neuronal Cultures

Astrocytes provide structural, metabolic and trophic support to neurons. They are directly involved in the regulation of neuronal transmission and synaptic activity and respond to the synaptic release and remove neurotransmitters from the extracellular fluid. The dysfunction of astrocytes has been implicated in multiple neurotoxicities, including those associated with drugs of abuse. Methamphetamine (METH) has long-lasting neurotoxic effects, yet little is known about the mechanisms that govern METH-induced neural dysfunction, and especially the astrocytic control over the extracellular milieu. The purpose of this study was to clarify the response of astrocytes and neurons treated with METH and determine their relative sensitivity to this drug of abuse. Confluent rat primary astrocyte and mesencephalic neuron cultures were treated for 24 hrs with 0, 0.1, 0.5 or 1 mM METH, and the initial rate of glutamate and glutamine uptake was measured over a 5 min period. Additional studies examined the effect of METH (24 hr exposure at similar concentrations) on oxidative endpoints, namely glutathione (GSH) levels, lactate dehydrogenase (LDH) release and isoprostane (IsoP) levels, considered to be the most accurate biomarker of lipid peroxidation. There was no effect of METH on the rates of glutamate and glutamine uptake, and these were indistinguishable from controls. However, METH concentration-dependently affected astrocytic and neuronal GSH levels, leading to a significant decrease in redox potential at all of the tested concentrations (p<0.05). METH also significantly enhanced astrocytic LDH release at the 0.5 and 1.0 mM exposures. Consistent with the changes in IsoPs, METH (0.5 and 1.0 mM) also increased the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), a transcription factor with a key role in regulating oxidative stress responses. However, this Nrf2 increased in expression was observed only in astrocytes and no effect was noted in neurons. Taken together, this study establishes that METH affects both astrocyte and neuronal functions, and that oxidative stress is a proximate mechanism for METH's-induced neurotoxicity on both cell types. Furthermore, in response to oxidative stress astrocytes efficiently upregulated Nrf2 nuclear translocation and transcription. These effects were absent in neurons. Combined with their lower content of GSH, these characteristics may account for the greater sensitivity of neurons to METH-induce toxicity.

Phase III, randomized, open-label, first-line study of gefitinib (G) versus carboplatin/paclitaxel (C/P) in selected patients (pts) with advanced non-small cell lung cancer (NSCLC) (IPASS): Evaluation of recruits in Japan

8044^

Background: The IRESSA Pan Asia Study (IPASS) demonstrated superiority of G vs C/P in 1,217 clinically selected chemonaïve pts in Asia with advanced NSCLC. PFS favored C/P initially then G, likely driven by different outcomes according to EGFR mutation (M) status. We report the planned analyses of 233 recruits in Japan (19% of overall population). Methods: From Mar 06 to Oct 07, chemonaïve, never/light ex-smokers with stage IIIB/IV NSCLC and adenocarcinoma histology were randomized to G 250 mg/day (n=114) or C (AUC 5 or 6)/P (200 mg/m2) (n=119). Primary objective was PFS in ITT population; a treatment by country interaction test (Japan vs other) was performed. Secondary endpoints were overall survival (OS), objective response rate (ORR, RECIST), QoL (FACT-L, TOI), symptom improvement (LCS subscale of FACT-L), and tolerability. Results: PFS results in pts in Japan did not significantly differ from other pts (interaction test p=0.4736). G demonstrated superior PFS compared with C/P (HR 0.69; 95% CI 0.51–0.94; p=0.0191); effect was not constant over time, favoring C/P initially then G. Preliminary OS (25% maturity; follow-up ongoing) was similar for G and C/P (HR 0.89; 95% CI 0.53–1.48). ORR for G was 41% vs 35% for C/P;odds ratio [OR] 1.34; 95% CI 0.78–2.30; p=0.2967. QoL improvement rate (TOI) was 43% for G and 28% for C/P (OR 1.92; 95% CI 1.11–3.34; p=0.0200); QoL (FACT-L 41 vs 43%; OR 0.94; 95% CI 0.56–1.60; p=0.8263) and symptom (LCS 42 vs 46%; OR 0.85; 95% CI 0.50–1.43; p=0.5340) improvement rates were similar for G and C/P. Tolerability profile was more favorable with G than C/P. There were no deaths due to ILD-type events (frequency 1.8% [G] vs 0% [C/P]). Conclusions: Efficacy and safety data for pts in Japan were generally consistent with overall population. G demonstrated improved PFS and ORR, similar OS, higher QoL (TOI) and similar symptom improvement rates, and a more favorable tolerability profile compared with C/P in chemonaïve, never/light ex-smokers with advanced NSCLC and adenocarcinoma histology. In IPASS, EGFR M status appeared to be a strong predictive biomarker for G efficacy compared with C/P.

[Table: see text]

ASCO Conflict of Interest Policy and Exceptions

In compliance with the guidelines established by the ASCO Conflict of Interest Policy (J Clin Oncol. 2006 Jan 20;24[3]:519–521) and the Accreditation Council for Continuing Medical Education (ACCME), ASCO strives to promote balance, independence, objectivity, and scientific rigor through disclosure of financial and other interests, and identification and management of potential conflicts. According to the ASCO Conflict of Interest Policy, the following financial and other relationships must be disclosed: employment or leadership position, consultant or advisory role, stock ownership, honoraria, research funding, expert testimony, and other remuneration (J Clin Oncol. 2006 Jan 20;24[3]:520). The ASCO Conflict of Interest Policy disclosure requirements apply to all authors who submit abstracts to the Annual Meeting.

For clinical trials that began accrual on or after April 29, 2004, ASCO's Policy places some restrictions on the financial relationships of principal investigators (J Clin Oncol. 2006 Jan 20;24[3]:521). If a principal investigator holds any restricted relationships, his or her abstract will be ineligible for placement in the 2009 Annual Meeting unless the ASCO Ethics Committee grants an exception. Among the circumstances that might justify an exception are that the principal investigator (1) is a widely acknowledged expert in a particular therapeutic area; (2) is the inventor of a unique technology or treatment being evaluated in the clinical trial; or (3) is involved in international clinical oncology research and has acted consistently with recognized international standards of ethics in the conduct of clinical research. NIH-sponsored trials are exempt from the Policy restrictions. Abstracts for which authors requested and have been granted an exception in accordance with ASCO's Policy are designated with a caret symbol (^) in the Annual Meeting Proceedings.

For more information about the ASCO Conflict of Interest Policy and the exceptions process, please visit www.asco.org/conflictofinterest .

Differential expression of apoptosis-related genes in the cochlea of noise-exposed rats

Exposure to intense noise induces apoptosis in hair cells in the cochlea. To identify the molecular changes associated with noise-induced apoptosis, we used quantitative real-time PCR to evaluate the changes in 84 apoptosis-related genes in cochlear samples from the sensory epithelium and lateral wall. Sprague-Dawley rats exposed to a continuous noise at 115 dB SPL for 2 h. The exposure caused a 40-60 dB threshold shift 4 h post-exposure that decreased to 20-30 dB 7 days post-exposure. These functional changes were associated with apoptotic markers including nuclear condensation and fragmentation and terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Immediately after the noise exposure, 12 genes were downregulated, whereas only one gene (Traf4) was upregulated. At 4 h post-exposure, eight genes were upregulated; three (Tnrsf1a, Tnfrsf1b, Tnfrst5) belonged to the Tnfrsf family, three (Bir3, Mcl1 and Prok2) have anti-apoptotic properties and one (Gadd45a) is a target of p53. At 7 days post-exposure, all the upregulated genes returned to pre-noise levels. Interestingly, the normal control cochlea had high constitutive levels of several apoptosis-related genes. These constitutively expressed genes, together with the inducible genes, may participate in the induction of cochlear apoptotic activity.

Epidemiology and clinical management of cardiomyopathies and heart failure in China

Heart failure (HF), a syndrome of clinical symptoms and signs, is the most serious and the final outcome of all heart diseases and as in other parts of the world it is a common cause for admission to hospital in the Chinese population. In this review the epidemiological data on cardiomyopathies, HF and current treatment for chronic HF among people living in China are summarised.

In vitro culture and differentiation of buffalo (Bubalus bubalis) spermatogonia

The objective of this study was to develop a culture system which could support buffalo spermatogonia differentiation into spermatids in vitro. Testes from 3- to 5-month-old buffaloes were decapsulated and seminiferous tubules were enzymatically dissociated to recover spermatogonia and sertoli cells. The cells were cultured in modified Dulbecco modified Eagle medium supplemented with different concentrations of foetal bovine serum, retinol, testosterone for 2 months at 37 degrees C. Spermatogonia and sertoli cells were identified with an antibody against c-kit or GATA4, respectively. The viability of spermatogonia in the media supplemented with different concentrations of serum was all significantly higher (p < 0.05) compared with that in the medium without serum. A-paired or A-aligned spermatogonia and spermatogonial colonies (AP-positive) were observed after 7-10 days of culture and spermatid-like cells with a flagellum (6-8 microm) appeared after 30 days of culture. For cultured conditions, retinol could not significantly promote the formation of spermatid-like cells (p > 0.05), whereas supplementation of testosterone could significantly promote (p < 0.05) the formation of spermatid-like cells after 41 days of culture. The expression of the spermatid-specific marker gene (PRM2) was identified after 30 days of culture by RT-PCR. Yet, the transition protein 1 (TP1, a haploid makers) was not detected. Meanwhile, spermatids developed in vitro were also confirmed by Raman spectroscopy. These results suggest that buffalo spermatogonia could differentiate into spermatids in vitro based on the analysis of their morphology, PRM2 expression and Raman spectroscopy. Yet, the normality of the spermatid-like cells was not supported by TP1 expression.

Downregulation of Wnt2 and beta-catenin by siRNA suppresses malignant glioma cell growth

Increasing evidence suggests that aberrant activation of Wnt signaling is involved in tumor development and progression. Our earlier study on gene expression profile in human gliomas by microarray found that some members of Wnt family were overexpressed. To further investigate the involvement of Wnt signaling in gliomas, the expression of core components of Wnt signaling cascade in 45 astrocytic glioma specimens with different tumor grades was examined by reverse transcription-PCR and immunohistochemistry. Wnt2, Wnt5a, frizzled2 and beta-catenin were overexpressed in gliomas. Knockdown of Wnt2 and its key mediator beta-catenin in the canonical Wnt pathway by siRNA in human U251 glioma cells inhibited cell proliferation and invasive ability, and induced apoptotic cell death. Furthermore, treating the nude mice carrying established subcutaneous U251 gliomas with siRNA targeting Wnt2 and beta-catenin intratumorally also delayed the tumor growth. In both in vitro and in vivo studies, downregulation of Wnt2 and beta-catenin was associated with the decrease of PI3K/p-AKT expression, indicating the interplay between Wnt/beta-catenin and PI3K/AKT signaling cascades. In conclusion, the canonical Wnt pathway is of critical importance in the gliomagenesis and intervention of this pathway may provide a new therapeutic approach for malignant gliomas.