Alendronate affects cartilage resorption by regulating vascular endothelial growth factor expression in rats

This study was performed to determine effects of alendronate on the tibial proximal epiphyseal cartilage undergoing endochondral ossification and the expression of vascular endothelial growth factor (VEGF) from the cartilage. Alendronate was injected subcutaneously every other day in postnatal Day 1 Sprague Dawley rats. The rats were sacrificed 3, 5, 7, and 10 days after the first injection. The effect of alendronate treatment for 10 days was demonstrated from the morphological change that the area of the secondary ossification center in the epiphysis was significantly smaller in the alendronate group than that in the control group (P < 0.05). Strong immunoreactivity to VEGF was observed in the hypertrophied chondrocytes and some proliferating chondrocytes in the epiphyseal cartilage at postnatal Day 5 and was decreased after the alendronate treatment for 5 days. Immunoreactivity was observed in not only hypertrophied cells but also the peripheral cartilaginous matrix adjacent to the vascular canals invading into the central portion of the cartilage at postnatal Day 7. This reactivity was also reduced considerably by the alendronate treatment for 7 days. The level of VEGF expression was reduced by the alendronate treatment at both the transcription and translation levels. However, the transcriptional level of the flt-1 and flk-1 receptors was relatively unaltered by the treatment. These results suggest that VEGF expression is required for vascular invasion into the developing cartilage and alendronate can affect its resorption by downregulating VEGF expression.

Interface ferromagnetism and orbital reconstruction in BiFeO3-La(0.7)Sr(0.3)MnO3 heterostructures

We report the formation of a novel ferromagnetic state in the antiferromagnet BiFeO3 at the interface with ferromagnet La(0.7)Sr(0.3)MnO3. Using x-ray magnetic circular dichroism at Mn and Fe L(2,3) edges, we discovered that the development of this ferromagnetic spin structure is strongly associated with the onset of a significant exchange bias. Our results demonstrate that the magnetic state is directly related to an electronic orbital reconstruction at the interface, which is supported by the linearly polarized x-ray absorption measurement at the oxygen K edge.

Measurement of w-InN/h-BN Heterojunction Band Offsets by X-Ray Photoemission Spectroscopy

X-ray photoelectron spectroscopy has been used to measure the valence band offset (VBO) of the w-InN/h-BN heterojunction. We find that it is a type-II heterojunction with the VBO being -0.30 ± 0.09 eV and the corresponding conduction band offset (CBO) being 4.99 ± 0.09 eV. The accurate determination of VBO and CBO is important for designing the w-InN/h-BN-based electronic devices.

First Report of Tobacco curly shoot virus Infecting Pepper in China

In recent years, whitefly-transmitted begomovirues (family Geminiviridae) have caused severe leaf curl disease on tobacco and tomato in southern China, but have not been found on pepper. In August 2009, pepper plants (Capsicum frutescens) grown in the field in Panzhihua City of Sichuan Province (southwestern China), from where the occurrence of begomoviruses has not been reported previously, showed stunting, leaf yellowing, and mild curling symptoms. To identify possible begomoviruses, total DNA was extracted from three infected pepper plants (SC117, SC118, and SC119) with typical symptoms. Using degenerate primer pair PA/PB specific for members of the genus Begomovirus (2), a 500-bp DNA fragment covering parts of the intergenic region and V2 gene of the genome of begomoviruses was amplified from all samples. No amplification was observed from healthy plant extracts. The PCR product from SC118 was cloned and two clones were chosen to be sequenced. Alignment of the partial DNA sequences revealed that the cloned products from isolate SC118 were nearly identical (98.5%) and most closely related to Tobacco curly shoot virus isolate Y35 (TbCSV-[China:Yunnan 35:2001]; Accession No. AJ420318) (96.9 and 97.3% identity, respectively). Therefore, the entire genome of isolate SC118 was sequenced. Overlap primers TbCSV-F(5'-CCGCCGTCTCAACTTCGACAG-3') and TbCSV-R(5'-ATCTGCTGGTCGCTTCGACAT-3') were designed to amplify the full-length genome of SC118. The complete genome sequence of SC118 was determined to be 2,746 nucleotides (Accession No. GU001879) long, with two open reading frames (ORFs) in the virion-sense strand and four ORFs in the complementary-sense strand, typical of the Old World begomoviruses. A comparison with other reported sequences of begomoviruses shows that the genome of SC118 shares the highest nucleotide sequence identity (99.7%) with TbCSV-[China:Yunnan 35:2001]. When PCR was used to detect TbCSV from the other two isolates (SC117 and SC119) with TbCSV specific primer pair Y35F1 and Y35+10R (4), which amplified the fragment covering the whole C2 and C3 genes and the partial C1 and V1 genes of the genome of TbCSV, an amplicon of approximately 1.0 kb was obtained from all samples. To determine whether a satellite molecule was associated with the three virus isolates, a universal betasatellite abutting primer pair (beta01 and beta02) was used (1). No amplification product was detected. In previous studies, it was demonstrated that only 11 isolates were associated with betasatellites among 39 TbCSV-infected, field-collected samples (3), and betasatellites could be associated with noncognate begomoviruses (4). Therefore, the three isolates examined in this study are too few to come to a conclusion that betasatellites are not associated with TbCSV infection of pepper plants. A detailed search for the presence of betasatellites needs to be conducted to draw a definitive conclusion. The above results confirmed that samples SC117, SC118, and SC119 were infected by TbCSV. To our knowledge, this is the first report of TbCSV on pepper in China. References: (1) R. W. Briddon et al. Mol. Biotechnol. 20:317, 2002. (2) D. Deng et al. Ann. Appl. Biol. 125:327, 1994. (3) Z. Li et al. Phytopathology 95:902, 2005. (4) L. Qing et al. Phytopathology 99:716, 2009.

Trends in the exploration of anticancer targets and strategies in enhancing the efficacy of drug targeting

A number of therapeutic targets have been explored for developing anticancer drugs. Continuous efforts have been directed at the discovery of new targets as well as the improvement of therapeutic efficacy of agents directed at explored targets. There are 84 and 488 targets of marketed and investigational drugs for the treatment of cancer or cancer related illness. Analysis of these targets, particularly those of drugs in clinical trials and US patents, provides useful information and perspectives about the trends, strategies and progresses in targeting key cancer-related processes and in overcoming the difficulties in developing efficacious drugs against these targets. The efficacy of anticancer drugs directed at these targets is frequently compromised by counteractive molecular interactions and network crosstalk, negative and adverse secondary effects of drugs, and undesired ADMET profiles. Multi-component therapies directed at multiple targets and improved drug targeting methods are being explored for alleviating these efficacy-reducing processes. Investigation of the modes of actions of these combinations and targeting methods offers clues to aid the development of more effective anticancer therapies.

Trends in the exploration of anticancer targets and strategies in enhancing the efficacy of drug targeting

A number of therapeutic targets have been explored for developing anticancer drugs. Continuous efforts have been directed at the discovery of new targets as well as the improvement of therapeutic efficacy of agents directed at explored targets. There are 84 and 488 targets of marketed and investigational drugs for the treatment of cancer or cancer related illness. Analysis of these targets, particularly those of drugs in clinical trials and US patents, provides useful information and perspectives about the trends, strategies and progresses in targeting key cancer-related processes and in overcoming the difficulties in developing efficacious drugs against these targets. The efficacy of anticancer drugs directed at these targets is frequently compromised by counteractive molecular interactions and network crosstalk, negative and adverse secondary effects of drugs, and undesired ADMET profiles. Multi-component therapies directed at multiple targets and improved drug targeting methods are being explored for alleviating these efficacy-reducing processes. Investigation of the modes of actions of these combinations and targeting methods offers clues to aid the development of more effective anticancer therapies.

Above-bandgap voltages from ferroelectric photovoltaic devices

In conventional solid-state photovoltaics, electron-hole pairs are created by light absorption in a semiconductor and separated by the electric field spaning a micrometre-thick depletion region. The maximum voltage these devices can produce is equal to the semiconductor electronic bandgap. Here, we report the discovery of a fundamentally different mechanism for photovoltaic charge separation, which operates over a distance of 1-2 nm and produces voltages that are significantly higher than the bandgap. The separation happens at previously unobserved nanoscale steps of the electrostatic potential that naturally occur at ferroelectric domain walls in the complex oxide BiFeO(3). Electric-field control over domain structure allows the photovoltaic effect to be reversed in polarity or turned off. This new degree of control, and the high voltages produced, may find application in optoelectronic devices.

Parasympathectomy induces morphological changes and alters gene-expression profiles in the rat submandibular gland

OBJECTIVE

The chorda-lingual (CL) nerve carries parasympathetic fibers to the hilum of the sublingual and submandibular glands (SMGs) and evokes the secretion of saliva. The effect of cutting the CL nerve on the biological processes in SMGs was investigated by examining the gene-expression profiles in the SMGs after a surgical parasympathectomy.

METHODS

At day 3 after the CL nerve cut, the changes in the SMGs at both the experimental cut and contralateral control sides were analysed by microarray and light microscopy. The expression levels of 6 selected genes were confirmed by real-time PCR, Western blot and immunofluorescence staining.

RESULTS

The wet weight of the parasympathectomised SMGs decreased significantly compared to that of the contralateral side (p<0.05). Histological analyses after the parasympathectomy showed a widened interacinar space as well as some atropic changes to the acini of the SMGs in the cut side. Microarray analysis revealed that twofold differential expression in mRNA expression in the parasympathectomized SMGs were detected in 88 genes (0.004%): 41 genes were overexpressed, 11 were underexpressed and 36 were unknown. Changes of the expression of 6 selected genes detected by Western blot and/or real-time PCR were consistent with the microarray data.

CONCLUSION

The important genes involved in biological processes for salivation were identified through a large-scale gene expression analysis.

Magnetically enhanced high-specificity virus detection using bio-activated magnetic nanoparticles with antibodies as labeling markers

This study describes magnetically driven suppression of cross-reactions among molecules. First, the magnetic nanoparticles are coated with bio-probes and dispersed in liquid. The bio-probes can then bind with homologous or heterologous bio-targets. When alternating-current (ac) magnetic fields are applied, magnetic nanoparticles rotate driven by ac magnetic fields. Thus, the bio-targets bound on the surface of magnetic nanoparticles experience a centrifugal force. The centrifugal force can be manipulated by adjusting the angular frequency of the rotating magnetic nanoparticles. The angular frequency is determined by the applied ac magnetic field frequency. Since the binding force for good binding is much higher than that of poor binding, frequency manipulation is needed for the centrifugal force to be higher than the poor-binding force but lower than the good-binding force. Therefore, poor binding which contributes to cross reactions between molecules can be suppressed efficiently by control of the ac magnetic field frequency.

Ultra-highly sensitive and wash-free bio-detection of H5N1 virus by immunomagnetic reduction assays

A platform for assaying avian influenza H5N1 viruses that involves measuring the ac immunomagnetic reduction of a magnetic reagent mixed with a detected sample is developed. The magnetic reagent contained magnetic nanoparticles coated with antibodies. To achieve an ultra-high sensitivity assay, a system utilizing a high-transition-temperature superconducting quantum interference device was used to sense the immunomagnetic reduction of the reagents. The results confirmed the ultra-high sensitivity of the immunomagnetic reduction assay on H5N1.

Evaluation of virtual screening performance of support vector machines trained by sparsely distributed active compounds

Virtual screening performance of support vector machines (SVM) depends on the diversity of training active and inactive compounds. While diverse inactive compounds can be routinely generated, the number and diversity of known actives are typically low. We evaluated the performance of SVM trained by sparsely distributed actives in six MDDR biological target classes composed of a high number of known actives (983-1645) of high, intermediate, and low structural diversity (muscarinic M1 receptor agonists, NMDA receptor antagonists, thrombin inhibitors, HIV protease inhibitors, cephalosporins, and renin inhibitors). SVM trained by regularly sparse data sets of 100 actives show improved yields at substantially reduced false-hit rates compared to those of published studies and those of Tanimoto-based similarity searching method based on the same data sets and molecular descriptors. SVM trained by very sparse data sets of 40 actives (2.4%-4.1% of the known actives) predicted 17.5-39.5%, 23.0-48.1%, and 70.2-92.4% of the remaining 943-1605 actives in the high, intermediate, and low diversity classes, respectively, 13.8-68.7% of which are outside the training compound families. SVM predicted 99.97% and 97.1% of the 9.997 M PUBCHEM and 167K remaining MDDR compounds as inactive and 2.6%-8.3% of the 19,495-38,483 MDDR compounds similar to the known actives as active. These suggest that SVM has substantial capability in identifying novel active compounds from sparse active data sets at low false-hit rates.

Wash-free, antibody-assisted magnetoreduction assays of orchid viruses

This study demonstrates the feasibility of wash-free magnetoreduction assays (MRA) of orchid viruses. A magnetic reagent, consisting of magnetic beads coated with antibodies and dispersed in water, was synthesized. By using a mixed-frequency alternative-current (ac) magnetosusceptometer, differences in the magnetic susceptibilities of the magnetic reagent before and after the addition of orchid solutions were measured. The results show significant advantages for MRA of orchid viruses.

6 LENTIVIRAL TRANSGENESIS IN MICE AND NONHUMAN PRIMATES

Transgenic technology is a powerful tool for investigating gene function and regulation in species ranging from fly to higher primates. The role of transgenic animal modeling has become more prominent in biomedical research; therefore, a highly efficient method for producing transgenic animals is critical for the advancement of animal modeling of genetic disorders, especially in species with limited access such as nonhuman primates. Lentiviral transgenesis is one of most efficient methods in generating transgenic animals, and has been applied in different species including mice, rats, pigs, and cattle. Here we evaluated lentiviral transgenesis by an in-depth investigation on the effect of gene construct and the method of viral delivery in mice; thus the prospect of creating transgenic nonhuman primates can be assessed. Lentiviruses carrying 25 different gene constructs in the same viral backbone were created and microinjected into the cytoplasm or the perivitelline space (PVS) of mouse zygotes; these zygotes were then compared to those subjected to the traditional pronuclear injection (PI) method. Embryo development was not affected by PVS, whereas intracytoplasmic injection produced a mild effect on embryo development, which was dependent on the manipulation skill. We found that intracytoplasmic injection of lentivirus had the highest transgenic rate (weaned pups) of approximately 54.22% (199/367), whereas the transgenic rate using PVS injection was 40.74% (22/54). However, the transgenic rate of PI was only 9.09% (4/44), which was significantly lower than the other two methods. Germline transmission was confirmed in over 90% of the transgenic lines produced by lentiviral gene transfer. In addition to the effect due to gene delivery method, variations in gene transfer efficiency were also observed when lentiviruses with different constructs were used. Our interest was to translate the lentiviral gene transfer technique into nonhuman primates for the development of a model for human disease. We evaluated the in vitro developmental rate of Rhesus macaques embryos that were microinjected into the PVS with lentiviruses carrying mutant genes leading to neurodegenerative diseases. The blastocyst rate of the lentivirus injection group (26%; 62/238) was not different from that of the control (25%; 13/52), which was without lentivirus injection. This indicates the feasibility of applying the lentiviral gene transfer technique to nonhuman primates. We carried out embryo transfers to surrogate female monkeys; however, the confirmation of pregnancy and the success of a developing nonhuman primate model of human disease were not available at the time of this writing. Here we demonstrate that lentiviral transgensis by cytoplasmic injection or PVS injection is a promising method to generate transgenic animals at high efficiency, and is superior to the traditional methods. Thus the production of a nonhuman primate model of human genetic diseases is foreseeable, and will have a significant impact on transgenic animal modeling as well as the advancement of biomedicine. This work was supported by the NCRR/NIH.

Increased apoptosis and decreased proliferation of colorectal cancer cells using insulin-like growth factor binding protein-4 gene delivered locally by gene transfer

OBJECTIVE

Insulin-like growth factor (IGF)-I induces proliferation of transformed cells. Its binding proteins (IGFBP) are involved in local regulation of IGF. This study assessed the effects of overexpression of IGFBP-4 on the development of cancer in vivo.

METHOD

Nude mice were subcutaneously inoculated with HT-29 colorectal cancer cells (3 x 10(6)). When the tumour became visible (1 week after inoculation), animals received either 150 microg of mammalian expression vector containing IGFBP-4 cDNA or vector alone (n = 6 each) by peritumoural injection. Tumour size was measured during the growth. After 3 weeks of IGFBP-4 induction, animals were killed and tumour tissue samples were collected for examining the level of IGFBP-4 expression. Tumour mitotic activities were determined by counting numbers of mitotic cells on the tissue section. Apoptosis was investigated by terminal deoxynucleotidyl transferase-mediated dUDP nick end labelling assay.

RESULTS

Following IGFBP-4 treatment, tumour showed large necrotic areas, significantly increased numbers of apoptotic cells (36.67 +/- 7.36 vs 7.07 +/- 1.91, P < 0.01 vs control), decreased cells undergoing mitosis (2.31 +/- 0.32 vs 3.61 +/- 0.27, P < 0.01 vs control) and higher expression of IGFBP-4 (P < 0.05 vs control).

CONCLUSION

IGFBP-4 gene transfer increased apoptosis and decreased mitosis, but tumour volume was not significantly altered possibly due to cellular debris filling the centre of tumours.

Impedance match of long-wavelength electromagnetic waves incident into magnetic photonic crystals

By utilizing an effective-medium method, the effective dielectric constant and effective magnetic permeability of magnetic photonic crystals at long-wavelength limits were calculated. We also examined the impedance ratio when a long-wavelength electromagnetic wave is incident to a magnetic photonic crystal. In this work, we focus on investigating the impact of the magnetic permeability of rods forming magnetic photonic crystals on the impedance ratio. Furthermore, we analyze the dependencies of the incident angle at impedance match on the magnetic permeability and filling factor of rods.

Analysis of the contributions of magnetic susceptibility to effective refractive indices of photonic crystals at long-wavelength limits

Since the magnetic susceptibility of materials is significant for low-wavelength regions, we investigated magnetic effects on refractive indices for long-wavelength electromagnetic waves propagating in photonic crystals (PCs). The PCs consisted of triangularly arrayed long rods, and were made of either dielectric or magnetic material, with air as the interstitial medium. According to calculated photonic band structures, the magnetism of rods plays a role in TM modes. Instead of using complicated calculating processes for band structures to find long-wavelength refractive indices, an analytic method was developed to estimate the effective refractive indices of long-wavelength TM modes. The refractive indices obtained through the band structures and the analytic method were consistent with each other. This demonstrates the validity of the analytic method, which we used to further clarify the physical mechanism involving the effects of rod magnetism on the refractive indices of long-wavelength TM modes propagating along magnetic PCs.

Lactic acid fermentation of food waste for swine feed

This study was conducted to determine the effects of lactic acid bacteria (LAB, Lactobacillus salivarius) inoculation on the microbial, physical and chemical properties of food waste mixture (FWM) stored at ambient temperature (25 degrees C) for 10 and 30 days. A complete pig diet including restaurant food waste, bakery by-product, barley and wheat bran, and broiler poultry litter was amended with LAB at the levels of 0.1%, 0.2%, 0.5% and 1.0% and fermented anaerobically. These treatments were compared with intact FWM before storage and non-anaerobically stored FWM. Non-anaerobic storage of FWM showed microbial putrefaction with the loss (P < 0.05) of water and water soluble carbohydrate (WSC) and increases (P < 0.005) in protein and fiber. Anaerobic fermentation of FWM with or without LAB seemed effective in both 10- and 30-day-storage. The addition of LAB inoculants to FWM showed a linear trend (P < 0.05) toward an increase in the number of total and lactic acid bacteria and toward the nutritional improvement with WSC increased and fiber decreased. Long-term (30 days) storage resulted in consistent reduction (P < 0.05) in numbers of total and lactic acid bacteria and pH and showed little change in chemical components, compared with short-term (10 days) storage. On the basis of these results, LAB inoculation improved fermentative characteristics of FWM. Among anaerobic treatments, further WSC increase and NDF reduction did not occur (P > 0.05) when LAB-added levels were over 0.2%. Based on these observations the optimum level of LAB addition to FWM was 0.2%.

Effect of bevacizumab (BV) and chemotherapy (CT) on serum levels of vascular endothelial growth factor receptor-2 (sVEGFR-2) in patients with inflammatory and locally advanced breast cancer

13003

Background: VEGFR-2 is a principal mediator of angiogenesis. The effects on sVEGFR-2 after anti-angiogenesis therapy are unknown. Methods: Twenty-one patients (pts) with breast cancer underwent neoadjuvant treatment with BV for 1 cycle (C1) followed by 6 cycles of BV, CT and filgrastim. Blood was collected at baseline (BL), post-cycles 1, 4 and 7. Objectives were to correlate sVEGFR-2 changes after treatment with response, assess wound healing complications, and evaluate for tumor VEGFR-2 mutations. sVEGFR-2 levels were measured by ELISA. Exons 17–26 were sequenced on tissue samples from 20 pts at BL and post C1 to evaluate for VEGFR-2 mutations. Statistical testing is non-parametric. All p-values are two-tailed, with a p < 0.01 interpreted as a statistically significant difference. Results: Thirteen pts had a partial response (PR), 1 unconfirmed PR, 5 stable disease (SD), and 2 progressive disease (PD). Median sVEGFR-2 levels increased by 16% from BL to post C1 (p = 0.0003) and decreased by 19% post C1 to post C4 (p = 0.048). sVEGFR-2 levels were not associated with clinical response. sVEGFR-2 levels at BL did not correlate with other BL parameters: Ki67, microvessel density, VEGF-A, pVEGFR-2, VEGFR-2 or TUNEL (apoptosis). A moderate-weak correlation was seen between post C1 levels of sVEGFR-2 and pVEGFR-2 (r = 0.43). A moderate inverse correlation was seen in the relative difference of sVEGFR-2 and TUNEL from BL to post C1 (r = −0.59). Comparing pts with (n = 5) and without (n = 16) wound healing problems, median sVEGFR-2 levels were 11322 ng/ml and 7524 ng/ml at BL (p = 0.019), 13928 ng/ml and 10148 ng/ml post C1 (p = 0.029), and 10965 ng/ml and 7932 ng/ml post C4 (p = 0.042). In 40 samples where tumor VEGFR-2 sequencing was obtained, no mutations were seen compared to the reference sequence. Conclusion: sVEGFR-2 levels rose significantly following BV alone but were not associated with response. There is a suggestion that sVEGFR-2 may correlate with activated VEGFR2 and a decrease in apoptosis. sVEGFR-2 levels were higher in pts with wound healing problems and may predict pts at higher risk of this complication. There were no mutations of VEGFR2.

[Table: see text]