[The construction and the expression of V5 epitope fused human androgen receptor vector in the yeast cell]

When we try to establish the gene recombinant yeast cell to screen the androgenic endocrine disruptors, the key procedure is the androgen receptor (AR) expression in the yeast cell. For this purpose, we obtained the GPD (glyceraldehyde-3-phosphote dehydrogenase) promoter from the yeast genosome of W303-1A using PCR system and inserting it into Swa I and BamH I sites of pYestrp2. The new constructed vector was named pGPD. The V5 epitope tag DNA with a 5'-BamH I and a 3'-EcoR I sticky end was cloned into the corresponding site of the pGPD vector to yield the vector of pGPDV5. The 2 723 bp full length AR ORF amplified by PCR from pcDNA3.1/AR was fused to V5 epitope tag DNA in pGPDV5 to give the AR yeast expression vector of pGPDV5/AR. This fused vector was transformed into the yeast cell (W303-1A). Western blot was used to detect the V5 fused protein of AR, in the protocol of which the primary monoclonal antibody (IgG(2a)) of mouse anti-V5 and the polyclonal secondary antibody of goat anti-mouse (IgG) linked to horseradish peroxidase (HRP) were used to detect the specific protein in the given sample of the transformed yeast extract. The result showed that the fused protein of AR was expressed successfully in the yeast cell.

Salmonella enterica serovar Typhi plasmid pR ST98 -mediated inhibition of autophagy promotes bacterial survival in infected fibroblasts

pR (ST98) is a chimeric plasmid isolated from Salmonella enterica serovar typhi (S. typhi) and mediates both drug-resistance and virulence of S. typhi. Autophagy has been recently reported as an important component of the innate immune response against intracellular pathogen. In this study, we investigated the effect of pR (ST98) on cellular autophagy, apoptosis and bacterial survival in infected fibroblasts. S. typhi strain ST 8 carrying pR (ST98) , Salmonella typhimurium strain SR-11 carrying a 100 Kb virulent plasmid, and avirulent S. typhi strain ST(10) without plasmid were tested in this experiment. Results showed that embryonic fibroblasts infected with ST(8) containing pR (ST98) had decreased autophagy accompanied by increased bacterial survival and apoptosis. Further study showed that autophagy inducer rapamycin reversed pR (ST98) -mediated inhibition of autophagy and reduced apoptosis in infected fibroblasts. Our data indicate that pR (ST98) can inhibit autophagy, thus facilitating S. typhi survival and promoting apoptosis of host cells. This study contributes to understanding the underlying mechanism of pR (ST98) -mediated virulence in S. typhi.

Occipital somites guide motor axons of the accessory nerve in the avian embryo

The accessory nerve (nervus accessorius) displays a unique organization in that its axons ascend along the rostrocaudal axis after exiting the cervical spinal cord and medulla oblongata and thereafter project ventrally into the periphery at the first somite level. Little is known about how this organization is achieved. We have investigated the role of somites in the guidance of motor axons of the accessory nerve using heterotopic transplantations of somites in avian embryos. The formation of not only accessory nerve but also the vagal nerve was affected, when a more caudal occipital somite (somites 2-4) was grafted to the position of the first occipital somite. Our study reveals that only the first occipital somite permits the development of ventral projection of accessory axons, a process that is inhibited by more caudal occipital somites.

[Establishment of recombinant Lac Z reporter gene-transformed yeast cells for bioassay of androgen-like compounds in environment]

OBJECTIVE

To establish the yeast-based bioassay system for the androgenic endocrine disruptors in the environment.

METHODS

The recombinant gene-transformed yeast cells were constructed based on two episomal vectors. In the expression vector, the expression of androgen receptor (AR) gene was driven by 3-glyceraldehydephosphate dehydrogenase (GPD) promoter and the gene was fused to V5 epitope; in the reporter vector, the expression of the Lac Z gene as a report gene was under the control of the androgen response element (ARE). The vectors were transformed into yeast cells (W303-1A) to construct the yeast-based bioassay system. The sensitivity of this assay system was evaluated by the androgenic compounds (dihydrotestosterone, DHT and testosterone propionate, TP)and the specificity of this system by the estrogenic compounds (17β-estradiol, estriol, estrone, diethylstilbestrol and ethinyl estradiol).

RESULTS

Both DHT and TP yielded a significant dose-effect model with the recombinant gene-transformed yeast cells, indicating that this yeast bioassay system has a high sensitivity. Moreover, the assay also exhibited a high specificity in that the yeast cells had no dose-effect relationship with the different concentrations of five estrogens (17β-estradiol, estriol, estrone, diethylstilbestrol and ethinyl estradiol).

CONCLUSION

The recombinant yeast cells could be applied to screen for the androgen-like compounds in the environment.

Clinical evaluation with self-sequential longitudinal reference intervals: pregnancy outcome and neonatal thyroid stimulating hormone level associated with maternal thyroid diseases

OBJECTIVE

We attempted to evaluate maternal thyroid function in a new self-sequential longitudinal reference interval (SLRI) which we established recently. By this method, we analysed the correlation between pregnancy outcome, neonatal thyroid stimulating hormone (TSH) level and maternal thyroid diseases.

METHODS

A total of 1744 pregnant women participated in the study and 1747 babies were born from those women (three bore twins). The levels of TSH, free thyroxine (FT4) and thyroid peroxidase antibodies (TPO-Ab) of mothers were quantified by electrochemistry immunoassay (ECL). The levels of neonatal blood TSH were detected by time-resolved fluorescence immunoassay (TRFIA). All data were collected and statistically analysed by SPSS 13.0 software.

RESULTS

With our new SLRI method, we found that 0.11%-3.84% pregnant women would get thyroid diseases. Subclinical hypothyroidism was the most common maternal thyroid disorder. Being positive for thyroid peroxidase antibodies was a significant risk factor of subclinical hypothyroidism during pregnancy. The median, P2.5-P97.5, and interquartile range (IQR) of neonatal TSH (N-TSH) of 1747 babies were 2.72 mIU/L, 0.10-8.01 mIU/L and 2.62 mIU/L, respectively; 28.6% of pregnant women with thyroid diseases developed pregnancy complications. The prevalence was significantly higher than in the normal thyroid function group (p < 0.001). The levels of N-TSH were low correlated with maternal TSH levels (p < 0.05), but there were no significant correlations between N-TSH and maternal FT4 and maternal TPO-Ab (p > 0.05).

CONCLUSIONS

Thyroid disorders, especially subclinical hypothyroidism, are common in pregnant women. These disorders are associated with pregnancy and fetal outcome. Routine maternal thyroid function screening is important and should be recommended.

A new derivative of camptothecin, irinotecan hydrochloride (cpt-11) induces programmed cell-death in leukemia-lymphoma cell-lines

Irinotecan Hydrochloride (CPT-11) and 7-ethyl-10-hydroxycamptothecin (SN-38), which are both topoisomerase I inhibitors with potent antitumor effects in vivo and in vitro, were tested for the induction of programmed cell death (PCD) in leukemia/lymphoma cell lines. When the human T-cell leukemia cell line HUT-102 and the human promyelocytic leukemia cell line HL-60 cells were exposed to CPT-11, PCD characterized by a DNA fragmentation ladder of 180-200 bp in agarose gel electrophoresis and loss of cell viability was induced. The PCD inducing activity of SN-38, an active metabolite of CPT-11, was much more powerful than that of CPT-11. Besides inducing PCD in HUT-102 and HL-60 cells, SN-38 also induced PCD in the human erythroblast leukemia cell line K-562, which was resistant to CPT-11. Induction of PCD by SN-38 and CPT-11 was dose- and time-dependent. PCD in HUT-102 cells induced by SN-38 was prevented neither by aurintricarboxylic acid (ATA), an endonuclease inhibitor, as determine by DNA electrophoretic profiles and the number of viable cells, nor by the protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA). The present data suggest that the topoisomerase I inhibitors, SN-38 and CPT-11 exert antitumor activity through induction of PCD in involved cells, at least in part. The PCD-inducing activity of the topoisomerase II inhibitor VP-16 was also tested in the above three cell lines and compared with CPT-11 and SN-38.

Improvements to the Kunkel mutagenesis protocol for constructing primary and secondary phage-display libraries

Site-directed mutagenesis is routinely performed in protein engineering experiments. One method, termed Kunkel mutagenesis, is frequently used for constructing libraries of peptide or protein variants in M13 bacteriophage, followed by affinity selection of phage particles. To make this method more efficient, the following two modifications were introduced: culture was incubated at 25°C for phage replication, which yielded two- to sevenfold more single-stranded DNA template compared to growth at 37°C, and restriction endonuclease recognition sites were used to remove non-recombinants. With both of the improvements, we could construct primary libraries of high complexity and that were 99-100% recombinant. Finally, with a third modification to the standard protocol of Kunkel mutagenesis, two secondary (mutagenic) libraries of a fibronectin type III (FN3) monobody were constructed with DNA segments that were amplified by error-prone and asymmetric PCR. Two advantages of this modification are that it bypasses the lengthy steps of restriction enzyme digestion and ligation, and that the pool of phage clones, recovered after affinity selection, can be used directly to generate a secondary library. Screening one of the two mutagenic libraries yielded variants that bound two- to fourfold tighter to human Pak1 kinase than the starting clone. The protocols described in this study should accelerate the discovery of phage-displayed recombinant affinity reagents.

The expression and clinical significance of pSTAT3, VEGF and VEGF-C in pancreatic adenocarcinoma

Signal transducers and activators of transcription 3 (STAT3) is a central cytoplasmic transcription factor and regulates a number of pathways important in tumorigenesis including cell cycle progression, apoptosis, tumor angiogenesis, invasion and metastasis.This study aims to investigate the expression of pSTAT3, VEGF and VEGF-C in pancreatic adenocarcinoma and their relations to the clinicopathological features, tumor angiogenesis and prognosis. In the present study, the expression of pSTAT3, VEGF and VEGF-C and microvascular density (MVD) were examined via immunohistochemistry. The clinicopathological information was collected and patients were regularly followed up. The relationship between the parameters and the clinicopathological features were analyzed, and the univariate and multivariate prognostic factors were also analyzed. The expression of pSTAT3 in tumor tissues was significantly higher in contrast to that in normal tissues, and pSTAT3 was related to VEGF and VEGF-C expression, MVD, tumor size, lymphogenous status and TNM staging (P<0.05). Survival analysis suggested that tumor size, TNM staging, pSTAT3 and VEGF expression were risk factors of prognosis, but no independent factors were found. We concluded that pSTAT3, which was a risk factor of prognosis, was abnormally expressed in pancreatic adenocarcinoma and related to tumor size, TNM staging and lymphatic metastasis. pSTAT3 may promote tumor angiogenesis via up-regulating VEGF on protein and even gene levels, and enhance the early lymphatic metastasis through VEGF-C. Better understanding of STAT3 signaling pathways in angiogenesis may contribute to the development of novel therapeutic strategies in angiogenesis and metastasis of pancreatic cancer.

Combining transfer of TTF-1 and Pax-8 gene: a potential strategy to promote radioiodine therapy of thyroid carcinoma

Cotransfer of thyroid-specific transcription factor (TTF)-1 and Pax-8 gene to tumor cells, resulting in the re-expression of iodide metabolism-associated proteins, such as sodium iodide symporter (NIS), thyroglobulin (Tg), thyroperoxidase (TPO), offers the possibility of radioiodine therapy to non-iodide-concentrating tumor because the expression of iodide metabolism-associated proteins in thyroid are mediated by the thyroid transcription factor TTF-1 and Pax-8. The human TTF-1 and Pax-8 gene were transducted into the human thyroid carcinoma (K1 and F133) cells by the recombinant adenovirus, AdTTF-1 and AdPax-8. Re-expression of NIS mRNA and protein, but not TPO and Tg mRNA and protein, was detected in AdTTF-1-infected F133 cells, following with increasing radioiodine uptake (6.1-7.4 times), scarcely iodide organification and rapid iodide efflux (t(1/2) ≈ 8-min in vitro, t(1/2) ≈ 4.7-h in vivo). On contrast, all of the re-expression of NIS, TPO and Tg mRNA and proteins were detected in F133 cells coinfected with AdTTF-1 and AdPax-8. AdTTF-1- and AdPax-8-coinfected K1 and F133 cells could effectively accumulate radioiodine (6.6-7.5 times) and obviously retarded radioiodine retention (t(1/2) ≈ 25-30-min in vitro, t(1/2) ≈ 12-h in vivo) (P<0.05). Accordingly, the effect of radioiodine therapy of TTF-1 and Pax-8 cotransducted K1 and F133 cells (21-25% survival rate in vitro) was better than that of TTF-1-transducted cells (40% survival rate in vitro) (P<0.05). These results indicate that single TTF-1 gene transfer may have limited efficacy of radioiodine therapy because of rapid radioiodine efflux. The cotransduction of TTF-1 and Pax-8 gene, with resulting NIS-mediated radioiodine accumulation and TPO and Tg-mediated radioiodine organification and intracellular retention, may lead to effective radioiodine therapy of thyroid carcinoma.

SAS+ Planning as Satisfiability

Planning as satisfiability is a principal approach to planning with many eminent advantages. The existing planning as satisfiability techniques usually use encodings compiled from STRIPS. We introduce a novel SAT encoding scheme (SASE) based on the SAS+ formalism. The new scheme exploits the structural information in SAS+, resulting in an encoding that is both more compact and efficient for planning. We prove the correctness of the new encoding by establishing an isomorphism between the solution plans of SASE and that of STRIPS based encodings. We further analyze the transition variables newly introduced in SASE to explain why it accommodates modern SAT solving algorithms and improves performance. We give empirical statistical results to support our analysis. We also develop a number of techniques to further reduce the encoding size of SASE, and conduct experimental studies to show the strength of each individual technique. Finally, we report extensive experimental results to demonstrate significant improvements of SASE over the state-of-the-art STRIPS based encoding schemes in terms of both time and memory efficiency.

Origin of strong white electroluminescence from dense Si nanodots embedded in silicon nitride

Strong white electroluminescence (EL) from SiN-based devices containing Si nanodots with a density of more than 4.6×10(12)cm(2) was investigated. The white EL illustrates enhanced light emission with increasing applied voltage and can be divided into two components, a dominant peak at ~710 nm and weak one at ~550 nm, which are close to those of the PL spectra optically pumped by the 325 and 488 nm lines, respectively. Based on the PL characteristics, we propose that the dominant EL band arises from the band-to-band recombination in the dense Si nanodots where quantum confinement plays a decisive role in the light emission, whereas the weak EL band originates from the radiative Si dangling bond (K⁰) centers in the silicon nitride matrix.

Isolation of monobodies that bind specifically to the SH3 domain of the Fyn tyrosine protein kinase

Fyn is a nonreceptor protein tyrosine kinase that belongs to a highly conserved kinase family, Src family kinases. Fyn plays an important role in inflammatory processes and neuronal functions. To generate a synthetic affinity reagent that can be used to probe Fyn, a phage-display library of fibronectin type III monobodies was affinity selected with the Src Homology 3 (SH3) domain of Fyn and three binders were isolated. One of the three binders, G9, is specific in binding to the SH3 domain of Fyn, but not to the other members of the Src family (i.e. Blk, Fgr, Hck, Lck, Lyn, Src and Yes), even though they share 51-81% amino acid identity. The other two bind principally to the Fyn SH3 domain, with some cross-reactivity to the Yes SH3 domain. The G9 binder has a dissociation constant of 166±6nM, as measured by isothermal titration calorimetry, and binds only to the Fyn SH3 domain out of 150 human SH3 domains examined in an array. Interestingly, although the G9 monobody lacks proline in its randomized BC and FG loops, it binds at the same site on the SH3 domain as proline-rich ligands, as revealed by competition assays. The G9 monobody, identified in this study, may be used as a highly selective probe for detecting and purifying cellular Fyn kinase.

Assessment of D216H DYT1 polymorphism in a Chinese primary dystonia patient cohort

BACKGROUND

The D216H single-nucleotide polymorphism (SNP) (rs1801968) in DYT1 exon 4 has been suggested to be a genetic modifier in primary dystonia.

METHODS

To further explore this question, we assessed rs1801968 variations in a cohort of 210 Chinese patients with primary dystonia devoid of DYT1 mutations.

RESULTS

We found that focal dystonia, specifically cervical dystonia, was the most common form of dystonia, with 8.1% of all the patients having a positive family history of dystonia. No association of the D216H SNP with primary dystonia was identified. In a subsequent subgroup analysis, the 216H allele was found to occur more frequently in patients with writer's cramp, but no correlation was found between the allele and other forms of dystonia or age of onset.

CONCLUSIONS

Our findings do not confirm that the allele contributes to the risk of D216H SNP primary dystonia.

Radioiodine therapy of thyroid carcinoma following Pax-8 gene transfer

The thyroid transcription factor Pax-8 could bind with the promoter/enhancer of thyroid-specific genes such as thyroglobulin (Tg), thyroperoxidase (TPO) and sodium iodide symporter (NIS), and regulate the expression of these proteins in thyrocyte. Promoting iodide accumulation in tumor cells by re-expression of Pax-8 provides a possible strategy for radioiodine therapy of tumor. Therefore, we investigated the effect of Pax-8 gene transfer on radioiodine therapy of thyroid carcinoma. The human Pax-8 gene was transfected into the human thyroid carcinoma (K1 and F133) cells by the recombinant adenovirus vector. Although the NIS mRNA was not detected, the expression of mRNA and proteins of Tg and TPO in AdPax-8-infected F133 cells were activated by Pax-8. Iodide uptake in thyroid carcinoma cells was reactivated by Pax-8 (increasing 3.3-fold in K1 cells and 5.7-fold in F133 cells). Moreover, Pax-8 promoted iodide organification and the retention time of iodine in Pax-8-expressing cells apparently prolonged in vitro and in vivo (P<0.05). Pax-8-expressing thyroid carcinoma cells were selectively killed by radioiodine. The AdPax-8-infected tumors in vivo clearly visualized in scanning images at 12 h after administration of radioiodine. These results indicate that Pax-8 can promote iodide uptake, and specifically prolong the retention time of iodide in thyroid cancer in vitro and in vivo by promoting the expression of TPO and Tg proteins. Pax-8 gene transfection may lead to effective radioiodine therapy of tumor.

Factors predicting the cumulative outcome of IVF/ICSI treatment: a multivariable analysis of 2450 patients

BACKGROUND

Knowing predictors of pregnancy in IVF is helpful for clinicians to individualize the treatment plans and improve patient counseling and for patients to decide whether to undergo infertility treatment. The aim of the study was to identify independent predictors of the chance of clinical pregnancy after a completed IVF/ICSI cycle (fresh plus cryopreserved embryos transferred from one stimulated cycle) and to compare the predictive value of important predictors identified.

METHODS

This was a single center, retrospective study of 2450 infertile women undergoing their first IVF treatment between 2002 and 2007. A bootstrapping stepwise variable selection algorithm was performed to identify independent predictors of clinical pregnancy chance from a list of 27 candidate variables. Multivariable logistic regression was used for assessing the effects of predictors. Proportion of explained variation analysis and concordance index were adopted to compare the predictive value of factors.

RESULTS

The following nine independent predictors were included in the final multivariable model: total number of good-quality embryos, total number of embryos, age, antral follicle count, fertilization rate, duration of infertility, endometrial thickness, number of 10-14-mm follicles and progesterone level on the day of hCG injection. The model was cross-validated internally in the training data and validated externally in an independent data with robust performance. The stratified analysis demonstrated that the total number of good-quality embryos was a better predictor of clinical pregnancy chance after a completed IVF/ICSI cycle than age for women <40 years, whereas age was a better predictor for women ≥ 40 years. The restricted cubic spline analysis revealed the relationship between the total number of good-quality embryos and log-odds of achieving a clinical pregnancy was nonlinear.

CONCLUSIONS

Quality and quantity of the whole embryos are the two most important predictors of the cumulative outcome in IVF/ICSI among independent predictors indentified. The importance of embryo quality on cumulative outcome in IVF/ICSI increases with increasing age.

Control of postharvest Botrytis fruit rot of strawberry by volatile organic compounds of Candida intermedia

A study was conducted to identify volatile organic compounds or volatiles produced by Candida intermedia strain C410 using gas chromatography-mass spectrometry, and to determine efficacy of the volatiles of C. intermedia in suppression of conidial germination and mycelial growth of Botrytis cinerea and control of Botrytis fruit rot of strawberry. Results showed that, among 49 volatiles (esters, alcohols, alkenes, alkanes, alkynes, organic acids, ketones, and aldehydes) identified from C. intermedia cultures on yeast extract peptone dextrose agar, two compounds, 1,3,5,7-cyclooctatetraene and 3-methyl-1-butanol, were the most abundant. Synthetic chemicals of 1,3,5,7-cyclooctatetraene; 3-methyl-1-butanol; 2-nonanone; pentanoic acid, 4-methyl-, ethyl ester; 3-methyl-1-butanol, acetate; acetic acid, pentyl ester; and hexanoic acid, ethyl ester were highly inhibitory to conidial germination and mycelial growth of B. cinerea. Inhibition of conidial germination and mycelial growth of B. cinerea by volatiles of C. intermedia was also observed. Meanwhile, results showed that incidence and severity of Botrytis fruit rot of strawberry was significantly (P < 0.01) reduced by exposure of the strawberry fruit to the volatiles from C. intermedia cultures or C. intermedia-infested strawberry fruit. These results suggest that the volatiles of C. intermedia C410 are promising biofumigants for control of Botrytis fruit rot of strawberry.

Relaxation of a Strained Elastic Film on a Viscous Layer

Experiments were conducted with SiGe film islands on a layer of borophosphorosilicate glass (BPSG). Initially the SiGe is under compression. Upon annealing, the glass flows and the SiGe islands relax by both inplane expansion and wrinkling. This paper provides a two-dimensional (2D) model for inplane expansion. The results from the model are compared with the experiments with small SiGe islands. The effect of winkling, which is ignored in the present model, is discussed qualitatively.

Abstract P4-02-08: STAT Signaling in Endocrine Sensitive and Resistant Breast Cancer — A Potential Target for Therapy?

The STAT (for signal transducer and activators of transcription) family of molecules regulate cell growth, survival, and differentiation as important integrators of cytokine and growth factor receptor signaling. STAT3 and STAT5 have been implicated in endocrine resistance in breast cancer. We aimed to identify new modifiers of endocrine sensitivity in breast cancer using functional proteomic profiling of the estrogen/tamoxifen-sensitive MCF-7 cell line and its partially sensitive (LCC1) and fully resistant (LCC9) variants. Using an unsupervised analysis of the expression of 125 paired phosphorylated and non-phosphorylated epitopes in key oncogene and tumour suppressor pathways on antibody arrays, STAT1, STAT3, and their phosphorylated epitopes were differentially expressed between endocrine resistant and parental controls. Differential expression was confirmed by qRT-PCR and western blotting. The STAT1 inhibitor EGCG inhibited cell number in endocrine insensitive and resistant LCC1/LCC9 lines, while the STAT3 inhibitors static and WP1066 were equally effective in endocrine-resistant and parental lines. Reduction in cell number was shown to be due to induction of apoptosis rather than inhibition of proliferation. The effects of the STAT inhibitors were additive, rather than synergistic, when tested in combination with tamoxifen in vitro. Finally, expression of STAT 1 and STAT3 were measured by quantitative immunofluorescence in 54 invasive breast cancers and expression levels of STAT1 and STAT3 transcript analysed in 550 breast cancers from publicly available gene expression datasets (GSE2990, GSE12093, GSE6532). High expression of STAT1, and low expression of STAT3, were associated with a worse distant metastasis free survival (DMFS; RR 1.42 and 0.46; log-rank p=0.042 and P&lt;0.0001, respectively). When treatment with tamoxifen was considered, STAT1 expression was nearly predictive of DMFS (log-rank p=0.067), while STAT3 expression was predictive of DMFS (log-rank P&lt;0.0001). These results suggest that STAT signaling may be important in endocrine resistance, and that STAT inhibitors, particularly STAT1 inhibitors, may be effective therapies in breast cancer even in the resistant setting.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-02-08.

Targeting of tumor radioiodine therapy by expression of the sodium iodide symporter under control of the survivin promoter

To test the feasibility of using the survivin promoter to induce specific expression of sodium/iodide symporter (NIS) in cancer cell lines and tumors for targeted use of radionuclide therapy, a recombinant adenovirus, Ad-SUR-NIS, that expressed the NIS gene under control of the survivin promoter was constructed. Ad-SUR-NIS mediating iodide uptake and cytotoxicity was performed in vitro. Scintigraphic, biodistribution and radioiodine therapy studies were performed in vivo. PC-3 (prostate); HepG2 (hepatoma) and A375 (melanoma) cancer cells all exhibited perchlorate-sensitive iodide uptake after infection with Ad-SUR-NIS, ∼50 times higher than that of negative control Ad-CMV-GFP-infected cells. No significant iodide uptake was observed in normal human dental pulp fibroblast (DPF) cells after infection with Ad-SUR-NIS. Clonogenic assays demonstrated that Ad-SUR-NIS-infected cancer cells were selectively killed by exposure to ¹³¹I. Ad-SUR-NIS-infected tumors show significant radioiodine accumulation (13.3±2.85% ID per g at 2 h post-injection), and the effective half-life was 3.1 h. Moreover, infection with Ad-SUR-NIS in combination with ¹³¹I suppressed tumor growth. These results indicate that expression of NIS under control of the survivin promoter can likely be used to achieve cancer-specific expression of NIS in many types of cancers. In combination with radioiodine therapy, this strategy is a possible method of cancer gene therapy.

Large Seebeck coefficients of protonated titanate nanotubes for high-temperature thermoelectric conversion

Titanate nanotubes Na(2-x)H(x)Ti(3)O(7) produced by alkali hydrothermally treated ground TiO(2) aerogels are investigated as possible materials for high-temperature thermoelectric conversion by measuring their thermoelectric properties. Strikingly, the Seebeck coefficients increased sharply in the temperature range 745 to 1032 K, reaching a maximum of 302 muV/K. The electrical resistivity of the TNNTs ranged from 325 to 525 Omegam, which is lower than that of bulk TiO(2), and thermal conductivities at room temperature were also very low, ranging from 0.55 to 0.75 Wm(-1) K(-1). The hollow structure of the titanate nanotubes, with small, uniform diameters, is thought to be responsible for the ultralow thermal conductivity. The large thermoelectric power and ultralow thermal conductivity suggest that titanate nanotubes represent a new kind of p-type oxide thermoelectric material.

Fast-scanning high-flux microprobe for biological X-ray fluorescence microscopy and microXAS

There is a growing interest in the biomedical community in obtaining information concerning the distribution and local chemical environment of metals in tissues and cells. Recently, biological X-ray fluorescence microscopy (XFM) has emerged as the tool of choice to address these questions. A fast-scanning high-flux X-ray microprobe, built around a recently commissioned pair of 200 mm-long Rh-coated silicon Kirkpatrick-Baez mirrors, has been constructed at BioCAT beamline 18ID at the Advanced Photon Source. The new optical system delivers a flux of 1.3 x 10(12) photons s(-1) into a minimum focal spot size of approximately 3-5 microm FWHM. A set of Si drift detectors and bent Laue crystal analyzers may be used in combination with standard ionization chambers for X-ray fluorescence measurements. BioCAT's scanning software allows fast continuous scans to be performed while acquiring and storing full multichannel analyzer spectra per pixel on-the-fly with minimal overhead time (<20 ms per pixel). Together, the high-flux X-ray microbeam and the rapid-scanning capabilities of the BioCAT beamline allow the collection of XFM and micro X-ray absorption spectroscopy (microXAS) measurements from as many as 48 tissue sections per day. This paper reports the commissioning results of the new instrument with representative XFM and microXAS results from tissue samples.

Monoclonal antibody treatment to prolong the secondary cardiac allograft survival in alloantigen-primed mice

We have previously shown that costimulation blockade using a combination of monoclonal antibodies (mAbs) - CTLA4Ig, antibodies to CD154, LFA-1, and OX40L - can induce tolerance of cardiac allografts in mice with adoptively transferred CD4(+) memory T cells [1]. However, the effect of costimulatory blockade in secondary allograft rejection has not been studied. B6 mice that rejected BALB/c skin grafts for more than 4 weeks (defined as alloantigen-primed mice) were used as recipients. The recipient mice were treated with the mAbs to CD154, LFA-1, OX40L, and CD122 on days 0, 2, 4, and 6 after the secondary transplantation of BALB/c heart. The mean survival time (MST) of secondary cardiac allografts in rats treated with antibodies to CD154 and LFA-1 (2-antibodies approach) and those treated with antibodies to CD154, LFA-1, OX40L, and CD122 (4-antibodies approach) was greater than that of the controls (MST = 6.7 days, 22.2 days, and 3.2 days, respectively). The 4-antibodies approach prevented lymphocytic infiltration in the grafts, inhibited memory T-cells proliferation in the spleen, increased IL-10 secretion in the serum, and enhanced the expression of CD4(+) Foxp3(+) regulatory T cells (Tregs) in spleen. Expression levels of alloreactive antibodies were high in the recipient mice of experimental and control groups. Inhibiting the memory T cells by costimulation blockade extended allograft survival in secondary transplant models but could not induce tolerance of graft. Alloreactive antibodies may participate in alloresponse and play an important role in secondary cardiac allograft rejection.