Use of Cryopreserved Cells for Enabling Greater Flexibility in Compound Profiling

Measurement of intracellular calcium release following agonist challenge within cells expressing the relevant membrane protein is a commonly used format to derive structure-activity relationship (SAR) data within a compound profiling assay. The Fluorometric Imaging Plate Reader (FLIPR) has become the gold standard for this purpose. FLIPR traditionally uses cells that are maintained in continuous culture for compound profiling of iterative chemistry campaigns. This supply dictates that assays can only be run on 4 of 5 weekdays, or alternative cell culture machinery is required such that plating can occur remotely at the weekend. The data reported here demonstrate that high-quality compound profiling data can be generated from the use of cryopreserved cells and that these cells can also be plated at various densities to generate equivalent data between 24 and 72 h post-plating. Hence, the authors report a method that allows data generation throughout the week and without the requirement of highly automated cell culture or continuous culture. ( Journal of Biomolecular Screening 2008:354-362)

Estimation of bioconcentration factors using molecular electro-topological state and flexibility

Bioconcentration assessment is important in the scientific evaluation of risks that chemicals may pose to humans and environment and is a current focus of regulatory effort. In this work, a new QSAR model by adopting electronic topological properties and flexibility of chemicals to predict the bioconcentration factor (BCF) in fish was established based on a large number of diverse compounds. Multiple linear regression (MLR) and partial least squares (PLS) were used to build reliable QSARs, which were evaluated with internal five cross-validations (Qcv2) and an external validation (Qex2). The proposed MLR model showed reasonable predictivity of BCF (Qcv2 = 0.79,Qex2 = 0.79) and included seven molecular descriptors, namely SsCl, SaasC, SaaaC, SsNH2, Hmin, SssO, and Phia. The PLS model (Qcv2 = 0.83, Qex2 = 0.80) was shown to be slightly better than the MLR one in prediction accuracy, using six PLS latent components. In addition, the relationship between the log BCF and the theoretical calculated log Kow was extensively investigated. These studies may help to understand the factors influencing the bioconcentration process of chemicals and to develop alternative methods for prescreening of environmental toxic compounds.

The use of proteomics to study infectious diseases

Technology surrounding genomics, or the study of an organism's genome and its gene use, has advanced rapidly resulting in an abundance of readily available genomic data. Although genomics is extremely valuable, proteins are ultimately responsible for controlling most aspects of cellular function. The field of proteomics, or the study of the full array of proteins produced by an organism, has become the premier arena for the identification and characterization of proteins. Yet the task of characterizing a proteomic profile is more complex, in part because many unique proteins can be produced by the same gene product and because proteins have more diverse chemical structures making sequencing and identification more difficult. Proteomic profiles of a particular organism, tissue or cell are influenced by a variety of environmental stimuli, including those brought on by infectious disease. The intent of this review is to highlight applications of proteomics used in the study of pathogenesis, etiology and pathology of infectious disorders. While many infectious agents have been the target of proteomic studies, this review will focus on those infectious diseases which rank among the highest in worldwide mortalities, such as HIV/AIDS, tuberculosis, malaria, measles, and hepatitis.

Allogeneic mesenchymal stem cell and mesenchymal stem cell-differentiated chondrocyte suppress the responses of type II collagen-reactive T cells in rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is a T-cell-mediated systematic disease and is usually accompanied by articular cartilage damage. In the present study, we explored the effects of bone marrow-derived mesenchymal stem cells (MSCs) and MSC-differentiated chondrocytes (MSC-chondrocytes) on the responses of antigen-specific T cells in RA to type II collagen (CII) to evaluate the potential therapeutic value of MSCs in RA treatment.

METHODS

The effects of both MSCs and MSC-chondrocytes on the proliferation, activation-antigen expression (CD69 and CD25) and cytokine production [interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-10 and IL-4] of CII-reactive T cells in RA patients were investigated with the stimulation of CII or otherwise. CD3/annexin V staining was used to evaluate T-cell apoptosis in the inhibition. The role of transforming growth factor-beta1 (TGF-beta1) underlying the inhibition was also investigated.

RESULTS

MSCs failed to elicit positive responses of CII-reactive T cells, whereas they significantly suppressed CII-stimulated T-cell proliferation and activation-antigen expression in a dose-dependent fashion without inducing T-cell apoptosis. The inhibition was observed even after MSCs were added as late as 3 days after the initiation of stimulation. Moreover, MSCs inhibited both CD4+ and CD8+ T cells from producing IFN-gamma and TNF-alpha, while they up-regulated the levels of IL-10 and restored the secretion of IL-4. TGF-beta1 was confirmed to play a critical role in the inhibition. Throughout our study, MSC-chondrocytes shared similar properties with MSCs.

CONCLUSION

Both MSCs and MSC-chondrocytes suppressed CII-reactive T-cell responses to CII in RA, which suggested that MSCs could be a potential candidate for RA treatment in future if further confirmed in vivo.

Isolation of EF1gamma from calli regenerating SSH library in Maize (Zea mays)

18599Hong, a good Maize (Zea mays) inbred line as well as good transformation acceptor with high regeneration capacity, was used for isolating embryonic callus regeneration genes. Subtractive library was constructed by Suppression subtractive hybridization and screened by Reverse Northern Hybridization. The clones of No. 27 was randomly picked to sequence. NCBI blastx results showed the similarity to elongation factor 1gamma in rice.

Room-temperature ferromagnetism in carbon-doped ZnO

We report ferromagnetism in carbon-doped ZnO. Our first-principles calculations based on density functional theory predicted a magnetic moment of 2.02 mu(B) per carbon when carbon substitutes oxygen in ZnO, and an ferromagnetic coupling among magnetic moments of the carbon dopants. The theoretical prediction was confirmed experimentally. C-doped ZnO films deposited by pulsed-laser deposition showed ferromagnetism with Curie temperatures higher than 400 K. The measured magnetic moment based on the content of carbide in the films [(1.5-3.0) mu(B) per carbon] was in agreement with the theoretical prediction. The magnetism is due to the Zn-C system in the ZnO environment.

A comparison of some anthropometric parameters between an Italian and a UK population: "proof of principle" of a European project using MammoGrid

AIM

To demonstrate the use of grid technology to produce a database of mammograms and supporting patient data, specifically using breast density as a biomarker of risk for breast cancer, for epidemiological purposes.

METHOD

The cohort comprised 1737 women from the UK and Italy, aged 28-87 years, mean 54.7 years, who underwent mammography after giving consent to the use of their data in the project. Information regarding height, weight, and exposure data (mAs and kV) was recorded. The computer program Generate-SMF was applied to all films in the database to measure breast volume, dense breast volume, and thereby percentage density. Visual readings of density using a six-category classification system were also available for 596 women.

RESULTS

The UK and Italian participants were similar in height, but the UK women were significantly heavier with a slightly higher body mass index (BMI), despite being younger. Both absolute and percentage breast density were significantly higher in the Udine cohort. Images from the medio-lateral projection (MLO) give a significantly lower percentage density than cranio-caudal (CC) images (p<0.0001). Total breast volume is negatively associated with percentage density, as are BMI and age (p<0.0001 for all), although 80% of the variability in percentage density remains unexplained.

CONCLUSION

The study offers proof of principle that confederated databases generated using Grid technology provide a useful and adaptable environment for large quantities of image, numerical, and qualitative data suitable for epidemiological research using the example of mammographic density as a biomarker of risk for breast cancer.

The association between weight history and physical performance in the Health, Aging and Body Composition study

OBJECTIVE

Although the association between current obesity and physical disability is well known, the cumulative effect of obesity is unknown. Using data from the Health, Aging and Body Composition study, we examined the association between weight history in young and middle adulthood and weight status in late adulthood with physical performance in late adulthood.

DESIGN

Longitudinal cohort study.

SUBJECTS

White and black men and women aged 70-79 years at study baseline (n=2803).

MEASURES

Body mass index (BMI; kg/m(2)) was calculated using recalled height at age 25 and weight at age 25 and 50 and measured height and weight at ages 70-79. Physical performance at ages 70-79 was assessed using a short physical performance battery (SPPB) and a 400-m walk test.

RESULTS

In this well-functioning cohort, approximately 24% of men and 8% of women reported being overweight or obese (BMI > or =25 kg/m(2)) at age 25, 51% of men and 37% of women reported being overweight or obese at age 50, and 69% of men and 66% of women were overweight or obese at ages 70-79. Men and women who were obese (BMI > or =30 kg/m(2)) at ages 25, 50 and 70-79 had significantly worse SPPB scores and 400-m walk times than those who were normal weight. Women who were overweight (BMI 25-29.9 kg/m(2)) at ages 25, 50 and 70-79 also had significantly worse physical performance. Furthermore, men and women who had a history of being overweight or obese at ages 25 or 50 had worse physical performance compared to those who were normal weight throughout or who were overweight or obese at ages 70-79 but not in midlife or earlier.

CONCLUSIONS

Maintaining a healthy body weight throughout adulthood may play a role in preventing or delaying the onset of physical disability.

Reversal of streptozotocin-induced diabetes in rats by gene therapy with betacellulin and pancreatic duodenal homeobox-1

Ultrasound-targeted microbubble destruction (UTMD) was used to direct betacellulin (BTC) and pancreatic duodenal homeobox-1 (PDX1) to rat pancreas 48 h after islet destruction by streptozotocin (STZ). Sprague-Dawley rats were rendered diabetic by STZ injection. Controls included normal rats, STZ only without UTMD, and UTMD with DsRed reporter gene. Blood glucose increased dramatically in all rats 48 h after STZ, and continued to rise after UTMD with BTC alone. Blood glucose declined from day 3 to day 10 after UTMD with PDX1, but remained elevated (261+/-8 mg/dl). However, in rats treated with both BTC and PDX1, blood glucose remained below 200 mg/dl throughout day 10. This was accompanied by normalization of blood insulin and C-peptide. Histology demonstrated islet-like clusters of glucagon-staining cells in the rats treated with BTC and PDX1, but these clusters disappeared by 30 days after UTMD treatment. Although regeneration of insulin-producing islets was not seen, diabetes was reversed for up to 15 days after a single UTMD treatment by ectopic insulin production by pancreatic acinar cells. These cells co-expressed amylase and insulin and demonstrated several beta-cell markers by reverse transcription-PCR. Gene therapy by UTMD can reverse diabetes in vivo in adult rats by restoring pancreatic insulin production.

Polymorphisms of angiotensinogen and angiotensin-converting enzyme associated with lower extremity arterial disease in the Health, Aging and Body Composition study

The role of renin-angiotensin system (RAS) genes on the risk of lower extremity arterial disease (LEAD) in elderly people remains unclear. We assessed the relationship of genetic polymorphisms in RAS: G-6A, T174M and M235T of the angiotensinogen (AGT) gene, and the angiotensin-converting enzyme insertion/deletion (ACE_I/D) variant to the risk of LEAD in the Health, Aging and Body Composition (Health ABC) Study. This analysis included 1228 black and 1306 white men and women whose age ranged between 70 and 79 years at the study enrollment. LEAD was defined as ankle-arm index (AAI) <0.9. Genotype-phenotype associations were estimated by regression analyses with and without adjustment for established cardiovascular disease (CVD) risk factors. The proportion of LEAD was significantly higher in black (21.1%) than that in white elderly people (10.1%, P<0.0001). The distribution of AGT polymorphisms was also significantly different between black and white participants. There was no statistically significant association between the selected RAS genetic variants and LEAD after adjustment for age, antihypertensive medications, lipid-lowering medication, pack-year smoking, body mass index, low-density lipoprotein cholesterol, and prevalent diabetes and coronary heart disease. However, A-T haplotype of G-6A and M235T interacting with homozygous ACE_II (beta=-1.07, P=0.006) and with ACE inhibitors (beta=-1.03, P=0.01) significantly decreased the risk of LEAD in white but not in black participants after adjustment for the selected CVD risk factors. In conclusion, the study observed a gene-gene and gene-drug interaction for LEAD in the white elderly.

Giant axonal neuropathy

Giant axonal neuropathy (GAN) is a rare autosomal recessive disorder affecting both the central and peripheral nervous systems. Cytopathologically, the disorder is characterized by giant axons with derangements of cytoskeletal components. Geneticists refined the chromosomal interval containing the locus, culminating in the cloning of the defective gene, GAN. To date, many distinct mutations scattered throughout the coding region of the locus have been reported by researchers from different groups around the world. GAN encodes the protein, gigaxonin. Recently, a genetic mouse model of the disease was generated by targeted disruption of the locus. Over the years, the molecular mechanisms underlying GAN have attracted much interest. Studies have revealed that gigaxonin appears to play an important role in cytoskeletal functions and dynamics by directing ubiquitin-mediated degradations of cytoskeletal proteins. Aberrant accumulations of cytoskeletal-associated proteins caused by a defect in the ubiquitin-proteasome system (UPS) have been shown to be responsible for neurodegeneration occurring in GAN-null neurons, providing strong support for the notion that UPS plays crucial roles in cytoskeletal functions and dynamics. However, many key questions about the disease remain unanswered.

Lattice Monte Carlo simulation of coil-helix transition

An improved self-avoiding lattice model was put forward to study coil-helix transition via dynamic Monte Carlo simulation. Each residue occupies eight simple lattices. By introducing a virtual-imino group and a virtual-carbonyl group, the helical period is not necessarily to be an integer. The Gö-like restriction of hydrogen bonding interaction has also been partially released. The coil-helix transition was well reproduced and consistent with the Zimm-Bragg theory. Non-native hydrogen bonding interaction seems significant around transition temperature. In characterization of a statistically helical structure, a novel correlation function was put forward and verified.

91 PRODUCTION OF A CLONED BOER GOAT (CAPRA HIRCUS) BY SOMATIC CELL NUCLEAR TRANSFER

We reported the birth of a goat clone produced by somatic cell nuclear transfer. The fusion and activation protocols of reconstructed oocytes and embryo transfer procedure were optimized. The donors of somatic cells were fibroblasts derived from ear skin of a Boer goat while the recipient ooplasm was in vitro-matured oocytes of Huanghuai white goat, an Anhui native goat species. The reconstructed embryos were activated by ionomycin, 6-dimethylaminopurine (6-DMAP), and cytochalasin B (CB) singly or simultaneously (termed as Ionomycin, Ionomycin+6-DMAP, and Ionomycin+6-DMAP+CB). The result showed that the cleavage rate in single ionomycin was significantly lower than that in Ionomycin+6-DMAP and 6-DMAP+CB (34.38% vs. 69.85% and 72.02%; P &lt; 0.05). However, the cleavage rates and blastocyst rates had no significant difference after in vitro culture (P &gt; 0.05). When the cloned embryos were co-cultured with fetal mouse fibroblast monolayer, the blastocyst development rate increased. The reconstructed embryos were equilibrated 1–3 h, 3–6 h, and 6–9 h after fusion, and then activation was undertaken by ionomycin+6-DMAP. We found that the cleavage rates had no significant difference during 1–3 h and 3–6 h (72.58% vs. 72.97%; P &gt; 0.05), but both were significantly higher than during 6–9 h (64.40%) (P &lt; 0.05). A total of 491 reconstructed embryos were surgically transferred into 37 recipient surrogates, Huanghuai white goats with natural estrus. One of those who were treated with hCG after transfer was pregnant and gave birth to a live kid on 153 days. The lamb died accidentally 8 h after birth. The cloned offspring was then dissected and proved well in all organs. Staining of paraffin tissue slices of the viscera suggested that the organs developed well. Microsatellite analysis indicated that the lamb was derived from the somatic cell donor doe genetically.