Vitamin D deficiency in exclusively breast-fed infants

Exclusive breast-feeding is recommended up to 6 months of age with all its beneficial effects on child survival. Several studies have concluded that adequate intake of vitamin D cannot be met with human milk as the sole source of vitamin D. As breast-feeding rates increase, the incidence of vitamin D deficiency rickets is also expected to rise. One of the potential sources of vitamin D synthesis is in the skin from the ultraviolet rays of sunlight. Risk factors for developing vitamin D deficiency and rickets include low maternal levels of vitamin D, indoor confinement during the day, living at higher altitudes, living in urban areas with tall buildings, air pollution, darker skin pigmentation, use of sunscreen and covering much or all of the body when outside. In a study of 50 cases of hypocalcaemia reported from an urban tertiary care children's hospital in Chennai, 13 exclusively breast-fed infants presented with hypocalcaemia due to vitamin D deficiency and most of them with seizures. None of them had received vitamin D supplementation and all their mothers had biochemical evidence for vitamin D deficiency. This review discusses the rising incidence of vitamin D deficiency in infancy and the need to consider and implement methods to prevent the same by supplementation and increased exposure to sunlight without the hazards of ultraviolet rays on the skin. Further research to define the magnitude of vitamin D deficiency in exclusively breast-fed infants as a public health and paediatric problem and to recommend programmes to prevent the same are of utmost importance.

A novel histone deacetylase 8 (HDAC8)-specific inhibitor PCI-34051 induces apoptosis in T-cell lymphomas

We have developed a potent, histone deacetylase 8 (HDAC8)-specific inhibitor PCI-34051 with >200-fold selectivity over the other HDAC isoforms. PCI-34051 induces caspase-dependent apoptosis in cell lines derived from T-cell lymphomas or leukemias, but not in other hematopoietic or solid tumor lines. Unlike broad-spectrum HDAC inhibitors, PCI-34051 does not cause detectable histone or tubulin acetylation. Cells defective in T-cell receptor signaling were still sensitive to PCI-34051-induced apoptosis, whereas a phospholipase C-gamma1 (PLCgamma1)-defective line was resistant. Jurkat cells showed a dose-dependent decrease in PCI-34051-induced apoptosis upon treatment with a PLC inhibitor U73122, but not with an inactive analog. We found that rapid intracellular calcium mobilization from endoplasmic reticulum (ER) and later cytochrome c release from mitochondria are essential for the apoptotic mechanism. The rapid Ca(2+) flux was dependent on PCI-34051 concentration, and was blocked by the PLC inhibitor U73122. Further, apoptosis was blocked by Ca(2+) chelators (BAPTA) and enhanced by Ca(2+) effectors (thapsigargin), supporting this model. These studies show that HDAC8-selective inhibitors have a unique mechanism of action involving PLCgamma1 activation and calcium-induced apoptosis, and could offer benefits including a greater therapeutic index for treating T-cell malignancies.

283 EXPRESSION OF TRANSCRIPTION FACTORS AND MESENCHYMAL DIFFERENTIATION OF STEM CELLS DERIVED FROM WHARTON'S JELLY OF PORCINE UMBILICAL CORD

Wharton's jelly derived from mesoderm of umbilical cord matrix is an abundant source of stem cells such as mesenchymal and more primitive stem cells that don't raise the ethical issues associated with embryonic stem cells. The Oct-4 POU transcription factor, Nanog, and Sox-2 are expressed in embryonic stem cells and have been implicated in embryonic development and maintenance of pluripotency. The present study examined the expression of early transcription factors, Oct-4, Nanog, and Sox-2, and capability of differentiation to osteocytes, adipocytes, and chondrocytes of the cells of Wharton's jelly isolated from porcine umbilical cord. Wharton's jelly was obtained from the umbilical cord of post-natal piglets (immediately after birth). This tissue was diced into 2-mm-diameter explants and attached to tissue culture dishes. Cells were then cultured in DMEM/F12 supplemented with 10% fetal blood serum (FBS), 10 ng mL–1 basic fibroblast growth factor (bFGF), 1 nm dexamethasone, and 10 nm insulin at 38.5�C, 5% CO2 in air. Expression of Oct-4, Nanog, and Sox-2 by these cells was analyzed by immunocytochemistry and RT-polymerase chain reaction (PCR), and compared with expression by porcine bone marrow MSCs established in our laboratory. Osteogenic, adipogenic, and chondrogenic differentiation were induced following the protocols described earlier (Jin et al. 2007 Int. J. Dev. Biol. 51, 85–90; Mohana Kumar et al. 2007 Mol. Cells, in press). Cells isolated from Wharton's jelly expressed Oct-4, Nanog, and Sox-2 especially in colonies/clusters, as observed by immunocytochemistry and gene expression by RT-PCR, and this expression was higher than by MSCs isolated from bone marrow. Osteocytes were documented by the formation of the mineral nodules with alkaline phosphatase-positive cells and deposition of calcium. Differentiation into adipocytes was exhibited by oil red O staining of lipid vacuoles. Alcian blue staining for proteoglycans demonstrated the differentiation of chondrogenic cells. In conclusion, the results of the present study suggest that cells isolated from Wharton's jelly have properties of primitive pluripotency and multilineage differentiation. These stem cells, therefore, can serve as an easily accessible and expandable source possessing potential for preclinical applications using a large animal model. This work was supported by Grant No. 20070301034040 from Bio-organ, Republic of Korea.

167 EXPRESSION PATTERN OF GAP JUNCTIONAL CONNEXINS DURING IN VITRO AND IN VIVO PREIMPLANTATION EMBRYO DEVELOPMENT IN BOVINE

During preimplantation development, several connexin proteins are expressed and assembled into gap junctions in the plasma membrane at compaction but the functional significance of connexin diversity remains controversial. The present investigations were (i) to compare the expression pattern of a panel of gap junctional connexin (Cx) gene transcripts from in vitro-produced (IVP) under low (5%) and high (20%) oxygen (O2) concentrations and in vivo-derived (IVD) bovine embryos during various preimplantation stages, and (ii) to evaluate the expression of the same set of gene transcripts in blastocysts derived from IVP (low O2 concentration) and in vivo embryos following a conventional cryopreservation method using 1.5 m ethylene glycol (EG) (Hasler et al. 1997 Theriogenology 48, 563–579). Cumulus-oocyte complexes were matured in TCM199 supplemented with 10% FBS and hormones for 22 h at 39�C, 5% CO2 in air, and then inseminated and cultured in SOF medium for 7 days. IVD embryos were collected from 18 superovulated and artificially inseminated cows. In Experiment I, five pooled embryos from each developmental stage (2-, 4-, 8-, 16-cell, morula, and blastocyst) and embryo source (IVP under low and high O2 concentrations and IVD) and, in Experiment II, Day 7 IVP (low O2 concentration) and IVD blastocysts following cryopreservation and storage for at least 1 week were used for analyzing the expression pattern of gap junctional connexin (Cx30, Cx31, Cx32, Cx36, Cx43, and Cx45) gene transcripts using real-time RT-PCR (four replicates). Normalization of mRNAs at each developmental stage of bovine preimplantation embryos was performed by employing a similar amount of RNA at the reverse transcription (RT) step. This was followed by analyzing by qRT-PCR the target genes using GAPDH as a reference gene. Significant differences in gene expression were analyzed byANOVA and Student's t-test. Relative abundances (RA) of Cx30, Cx31, and Cx32 of IVD embryos were significantly (P < 0.05) higher at all stages compared to that of IVP embryos, except at the blastocyst stage for Cx32. Differences in Cx36 and Cx45 were observed at all stages, with the levels being higher (P < 0.05) in IVD than in IVP embryos. However, the differences at the 4-cell stage between the two embryo sources were not significant. The RA of Cx43 transcript in IVD embryos at 4- and 16-cell stages was higher (P < 0.05) than in IVP embryos, but did not differ at the 2-cell stage. Furthermore, there were differences at the 8-cell and blastocyst stages among IVD, and low and high O2 IVP embryos. Following cryopreservation, RA of all analyzed connexin transcripts of IVD blastocysts were significantly (P < 0.05) higher than that of the low O2 concentration. However, the expression levels in both embryo sources were lower compared to blastocysts before cryopreservation, except for Cx36. To the best of our knowledge, this is the first report on the differences in the expression pattern of a panel of gap junctional connexin gene transcripts during the key developmental stages of IVP embryos with direct comparisons of IVD counterparts.

Pneumoparotitis with subcutaneous emphysema

We report an adolescent with recurrent bilateral parotitis with pneumoparotitis and subcutaneous emphysema due to self pneumoinsufflation by a Valsalva like maneuver. Investigations for recurrent parotitis did not yield any clue. His la belle indifference, prolonged school absence and the presence of sibling rivalry helped us identify the psychological cause.

275 IN VITRO DIFFERENTIATION OF PORCINE MESENCHYMAL STEM CELLS INTO NEURON-LIKE CELLS

The unique self-renewal ability for multilineage differentiation makes mesenchymal stem cells (MSCs) a promising cell source for regenerative medicine. However, before adapting in clinical trials, there is a need for a systematic evaluation of the in vitro differentiation process and the functional identities of cells generated using animal model systems. We have previously reported that MSCs derived from porcine umbilical cord blood (pUCB), post-natal bone marrow, and young adult bone marrow with typical phenotypic properties differentiate in vitro into various cells types of mesodermal lineage (Jin et al. 2007 Int. J. Dev. Biol. 51, 85–90; Mohana Kumar et al. 2007 Mol. Cells, in press). In the present study, we examined whether porcine MSCs (pMSCs) obtained from different origins, such as UCB, post-natal (immediately after birth) bone marrow, and young adult (6 months old) bone marrow are capable of neuronal differentiation in vitro. Subconfluent cultures of pMSCs (2–5 passages) were induced to become neuroectodermal cells following the protocol described earlier (Woodbury et al. 2000 J. Neurosci. Res. 61, 364–370), with minor modifications. After induction, 75 80% of cells exhibited substantial morphological changes including appearance of a more spherical shape, with multipolar and extending processes arranged into a network-like structure. Besides acquiring a neuronal phenotype, pMSCs derived from different origins displayed the expression pattern of characteristic neural-specific markers including early, intermediate, and late neural cell types. Differentiated cells expressed markers such as nestin, microtubule-associated protein-2 (MAP-2), neuronal nuclei (NeuN), βIII-tubulin, neurofilament-M (NF-M), glial fibrillary acidic protein (GFAP), galactocerebroside (GalC), and myelin basic protein (MBP) by immunofluorescence analysis. Expression pattern was further confirmed by analyzing selected neuronal transcripts by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Neurally differentiated pMSCs from different origins showed significantly (P < 0.05) higher relative abundance of nestin, βIII-tubulin, NF-M, and GFAP, compared to cells in control. In conclusion, the morphological observations and expression of neuronal-specific markers support the fact that pMSCs from different origins possess the ability to differentiate in vitro into neuron-like cells upon exposure to appropriate stimuli. Furthermore, these findings provide additional support for the emerging concept that the establishment of cell lines from pMSCs can have a pivotal role in standardizing cell replacement strategies.

Synthesis and NMR spectral studies of N-chloroacetyl-2,6-diarylpiperidin-4-ones

A series of 2,6-diarylpiperidin-4-ones having electron withdrawing chloroacetyl group at the heterocyclic nitrogen were synthesized. Unambiguous characterizations of the synthesized compounds were achieved by one-dimensional ((1)H NMR and (13)C NMR) and two-dimensional (HOMOCOSY, NOESY and HSQC spectra for compounds 8 and 9 and HOMOCOSY spectrum only for 10) NMR spectroscopic data. The conformational preferences of N-chloroacetyl-2,6-diarylpiperidin-4-ones with and without alkyl substituent at C-3 and C-5 (8-14) have also been discussed using the spectral studies. The spectral data and extracted coupling constant values suggest that the compounds 8, 12 and 14 adopt flattened boat conformation whereas the remaining compounds exist in twist-boat conformations in solution with coplanar orientation of the chloroacetyl moiety present at the heterocyclic nitrogen. The substituent parameters for the chloroacetyl moiety on the heterocyclic ring carbons have also been derived and discussed elaborately on the basis of their steric, electronic and gamma-eclipsing interaction. This substituent at the nitrogen causes a substantial change on the chemical shifts of ring carbons and the associated protons.

Refined potential model for atomistic simulations of ionic liquid [bmim][PF6]

Refined parameters of an atomistic interaction potential model for the room temperature ionic liquid 1-n-butyl,3-methylimidazolium hexafluorophosphate are presented. Classical molecular dynamics simulations have been carried out to validate this fully flexible all-atom model. It predicts the density of the liquid at different temperatures between 300 and 500 K within 1.4% of the experimental value. Intermolecular radial distribution functions and the spatial distribution functions obtained from the new model are in close agreement with ab initio simulations. The calculated diffusion coefficients of ions and the surface tension of the liquid agree well with experiment.

Dynamics in a room-temperature ionic liquid: a computer simulation study of 1,3-dimethylimidazolium chloride

The transport properties and solvation dynamics of model 1,3-dialkylimidazolium chloride melt at 425 K is studied using molecular-dynamics simulations. Long trajectories of a large system have been generated and quantities such as the self-diffusion coefficient of ions, shear viscosity, and ionic conductivity have been calculated. Interestingly, the diffusion of the heavier cation is found to be faster than the anion, in agreement with experiment. The interaction model is found to predict a higher viscosity and lower electrical conductivity compared to experimental estimates. Analysis of the latter calculations points to correlated ion motions in this melt. The solvation time correlation function for dipolar and ionic probes studied using equilibrium simulations exhibits three time components, which include an ultrafast (subpicosecond) part as well as one with a time constant of around 150 ps. The ultrafast solvent relaxation is ascribed to the rattling of anions in their cage, while the slow component could be related to the reorientation of the cations as well as to ion diffusion.

Interstitial lung disease in infancy

OBJECTIVE

To describe the clinical profile of interstitial lung disease in infancy.

METHODS

A retrospective analysis of cases diagnosed to have ILD was carried out in Kanchi Kamakoti CHILDS Trust hospital over a period of 2 yr. Infants aged 1 month to 1 yr of age were included if they had (1) respiratory symptoms (Cough, tachypnea or crepitations) for at least 1 month (2) diffuse infiltrates on chest radiography (3) Hypoxemia as defined by oxygen saturation less than 90% by pulse oximetry and (4) High Resolution Computed Tomography (HRCT) of the chest revealing findings of interstitial infiltrates or ground glass pattern. Their case records were analyzed for clinical data, treatment and follow up details.

RESULTS

Of the 9 children, who were diagnosed to have ILD, 5 were boys and 4 were girls. The male: female ratio was 1.25: 1. The median age of onset of symptoms was 5 month. The common clinical features observed were tachypnea associated with chest indrawing (100%), cough (100%), hypoxia (100%), failure to thrive and fever (55%) each. The following radiographic patterns were observed in the chest skiagrams: reticulo-nodular pattern in 6(67%) and ground glass pattern in 3(33%). HRCT showed interstitial infiltrates in 6 (67%) and ground glass pattern in 3(33%). Evidence for cyto megalo virus (CMV) infection was detected in 5(56%), Adenovirus in 1 (11%) and Pneumocystis carinii (PCP) in 1(11%) infant. Open lung biopsy was performed in 2 infants, which detected CMV in 1 and PCP in the other. All children received oxygen therapy and systemic corticosteroids (oral/IV) in addition to specific therapy for infection and 3 of these infants succumbed to respiratory failure.

CONCLUSION

CMV Infection was the commonest cause of ILD in infancy in our study. However, the consequences on long term follow up in these infants need to be ascertained.

Ultra-structural changes and developmental potential of porcine oocytes following vitrification

This study evaluated the effects of exposure and/or vitrification of porcine metaphase II (MII) oocytes on their in vitro viability and ultra-structural changes with two experiments. Experiment 1 examined the effect of vitrified oocytes on microtubule localization, mitochondrial morphology, chromosome organization and the developmental rate in IVF control and vitrified oocytes. Oocytes matured for 44 h were subjected to IVF (IVF control). Oocytes matured for 42 h were exposed to cryoprotectants (CPA control), followed by 2h culture, and subjected to IVF. Oocytes vitrified at 42 h post-maturation were warmed, cultured for 2h, and subjected to IVF (vitrified). Experiment 2 evaluated the effect of oocytes freezing on development of ICSI with and without activation and parthenotes. Fresh and vitrified oocytes were subjected to ICSI with and without electrical activation. Cleavage and blastocyst rates were significantly (P<0.05) lower in vitrified IVF, parthenote and ICSI embryos than those in fresh counterparts. Between ICSI embryos from fresh oocytes and vitrified oocytes, the rates of blastocyst were significantly higher (P<0.05) in activated group than the group without activation. Significant differences (P<0.05) were observed in normal spindle configuration of vitrified (43.5%) compared to control (81.0%) oocytes, but no significant difference was observed between CPA exposed and control groups. In conclusion, porcine oocytes at MII stage are very sensitive to vitrification with altered microtubule localization and mitochondrial organization thus resulting in impaired fertilization and embryo development.

Sensitivity of primary hematopoietic tumors and tumor lines to the novel HDAC inhibitor PCI-24781

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PCI-24781 (formerly CRA-024781) is a novel HDAC inhibitor that is in phase I clinical trials in patients with solid and hematopoietic malignancies. PCI-24781 has favorable pharmacokinetic and pharmacodynamic profiles in animal models and in humans. In the present study we show that PCI-24781 potently induces cell death in a variety of hematopoietic cell lines derived from B-cell, T-cell and myeloid malignancies, and in primary acute leukemic blasts from bone marrow aspirates. In tumor cell lines, growth inhibition and apoptosis were noted at drug concentrations ≡ 0.125 μM and were accompanied by known biochemical markers of HDAC inhibition including histone and tubulin hyperacetylation. To demonstrate the potential clinical utility of PCI-24781 in hematologic tumors, primary leukemia samples were isolated from patients and screened for resistance to PCI-24781-induced growth arrest in vitro. Of these 25 primary samples (10 acute myelogenous leukemia (AML), 6 multiple myeloma (MM) and 9 acute lymphocytic leukemia (ALL)), some of which were derived from patients who had failed standard therapy, none was resistant to PCI-24781 at 0.5 μM and only 4 (1 AML, 2 MM, and 1 ALL) were considered resistant at 50 nM. Gene expression analysis using DNA microarrays on these primary tumor samples revealed alterations of gene expression consistent with HDAC inhibition and defined potential pathways of activity for this compound in these tumors. These results demonstrate that hematopoietic tumors and tumor-derived cell lines are highly sensitive in vitro to the novel HDAC inhibitor PCI-24781. The high sensitivity of primary tumor cells to treatment with PCI-24781 in vitro coupled with the favorable pharmacokinetics of this compound in humans suggests that patients with hematopoietic malignancies would be responsive to treatment with PCI-24781 in clinical trials.

No significant financial relationships to disclose.

Expression pattern of oxygen and stress-responsive gene transcripts at various developmental stages of in vitro and in vivo preimplantation bovine embryos

The present study examined the expression pattern of oxygen (O(2)) and stress-responsive gene transcripts at various preimplantation developmental stages of in vitro produced (IVP) and in vivo derived (IVD) bovine embryos. Embryos were produced in vitro from oocytes matured, fertilized and cultured in synthetic oviductal fluid (SOF) medium under low (5%) and high (20%) O(2) concentrations. In vivo embryos were derived from 18 superovulated and artificially inseminated cows. In IVP and IVD groups, embryos were collected at 2-, 4-, 8-, 16-cell morula and blastocyst stages at specific time points for gene expression analysis. The cleavage rates (69.8+/-4.8%) did not differ significantly, but blastocyst rates were significantly higher (28.5+/-3.7%) in low O(2) than those in high O(2) group (18.7+/-3.9%). Mean cell number in low O(2) (145+/-12) and high O(2) (121+/-73) IVP blastocyst were lower (P<0.05) than those of IVD blastocyst (223+/-25). The ICM ratio of IVD blastocyst (26+/-4) was lower (P<0.05) than that of IVP embryos under 5% O(2) (33+/-5) and 20% O(2) (34+/-4) concentrations, respectively. Using real time PCR, for the set of target transcripts (Glut1, Glut5, Sox, G6PD, MnSOD, PRDX5, NADH and Hsp 70.1) analyzed, there were differences in the mRNA expression pattern at 2-, 4-, 8-, 16-cell morula and Day 7 blastocyst stages between the two embryo sources. It can be concluded that, although in vitro bovine embryo culture in SOF medium under low (5%) O(2) concentration provided a more conducive environment in terms of blastocyst formation; differences in the total cell number and gene expression pattern between the IVP and IVD embryos reflected the effect of O(2) concentration.

Synthesis, stereochemistry and antimicrobial evaluation of some N-morpholinoacetyl-2,6-diarylpiperidin-4-ones

In a search for new leads towards potent antimicrobial agents, an array of novel N-morpholinoacetyl-2,6-diarylpiperidin-4-ones has been synthesized and their in vitro antibacterial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi and antifungal activity against Candida albicans, Rhizopus sp., Aspergillus niger and Aspergillus flavus were evaluated. Structure and stereochemistry of all the N-morpholinoacetyl-2,6-diarylpiperidin-4-ones have been analyzed using (1)H and (13)C NMR spectroscopic techniques. In all the cases, amide N-CO group is preferentially in coplanar orientation with respect to the dynamically averaged plane of the piperidone ring. Further, all the symmetrically substituted compounds 19, 23, 24, 26 and 27 are expected to adopt half boat conformations while other compounds 20-22 and 25 adopt twist-boat conformations. Structure-activity relationship results for these nine compounds have shown that compounds 26 and 27 exerted excellent antibacterial activity against all the bacterial strains used except 27 against S. aureus. Against C. albicans and A. flavus, compound 24 recorded excellent antifungal activities while against Rhizopus sp., compound 25 showed potent activities. The obtained results may be used as key step for the building of novel chemical compounds with interesting antimicrobial profiles comparable to that of the standard drugs.

Development and quality of porcine embryos in different culture system and embryo-producing methods

In this study, the developmental ability and cellular composition of porcine IVF, parthenote and somatic cell nuclear transfer (SCNT) embryos were evaluated following different in vitro culture systems. Group 1, embryos were cultured in NCSU-23 with 5.55 mM D-glucose (NCSU+) until day 6 on 20% O(2) or 5% O(2) (Group 2). Group 3, embryos were cultured in D-glucose-free NCSU-23 (NCSU-) with 0.17 mM Na pyruvate/2.73 mM Na lactate for 58 h and subsequently cultured in NCSU+ until day 6 (NCSU -/+) on 20% O2 or 5% O(2) (Group 4). IVF blastocysts did not differ significantly with O(2) concentrations, but differed significantly with major energy source (glucose and pyruvate/lactate). In Group 3 and 4 IVF blastocysts, the total cell number and apoptosis rates were not significantly different with different O(2) concentrations. Blastocyst rate, total cell number and apoptosis rate in Groups 3 and 4 parthenote embryos also were not significantly different. Parthenote and SCNT, under the same culture treatment, exhibited significant differences in blastocyst and apoptosis rates (47.5 +/- 16.1 vs. 24.0 +/- 4.0 and 4.9 +/- 9.0 vs. 22.8 +/- 23.3). Apoptosis-generating rate increased in the order parthenote, IVF and then SCNT. In conclusion, in vitro development of porcine embryos was not affected by O(2) concentrations but was affected by major energy source. Even so, the concentration of each major energy source and the timing of its inclusion in culture could accomplish relatively high embryonic development, the apoptosis rate stressed that more work still needs to be done in developing a better defined culture system that could support SCNT embryos equivalent to in vivo preimplantation porcine embryos.

Insights into the Structure and Dynamics of a Room-Temperature Ionic Liquid: Ab Initio Molecular Dynamics Simulation Studies of 1-n-Butyl-3-methylimidazolium Hexafluorophosphate ([bmim][PF6]) and the [bmim][PF6]−CO2 Mixture

Ab initio molecular dynamics (AIMD) studies have been carried out on liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) and its mixture with CO2 using the Car-Parrinello molecular dynamics (CPMD) method. Results from AIMD and empirical potential molecular dynamics (MD) have been compared and were found to differ in some respects. With a strong resemblance to the crystal, the AIMD simulated neat liquid exhibits many cation-anion hydrogen bonds, a feature that is almost absent in the MD results. The anions were observed to be strongly polarized in the condensed phase. The addition of CO2 increased the probability of this hydrogen bond formation. CO2 molecules in the vicinity of the ions of [bmim][PF6] exhibit larger deviations from linearity in their instantaneous configurations. The polar environment of the liquid induces a dipole moment in CO2, lifting the degeneracy of its bending mode. The calculated splitting in the vibrational mode compares well with infrared spectroscopic data. The solvation of CO2 in [bmim][PF6] is primarily facilitated by the anion, as seen from the radial and spatial distribution functions. CO2 molecules were found to be aligned tangential to the PF6 spheres with their most probable location being the octahedral voids of the anion. The structural data obtained from AIMD simulations can serve as a benchmark to refine interaction potentials for this important room-temperature ionic liquid.

Differential gene expression patterns in porcine nuclear transfer embryos reconstructed with fetal fibroblasts and mesenchymal stem cells

The present study compared the developmental ability and gene expression pattern at 4-cell, 8-cell, morula, and blastocyst stages of porcine nuclear transfer (NT) embryos from fetal fibroblasts (FFs) and mesenchymal stem cells (MSCs), in vitro fertilized (IVF), and in vivo derived embryos. MSC-NT embryos showed enhanced blastocyst formation, higher total cell number, and a low incidence of apoptosis compared to FF-NT embryos. Alterations in the expression pattern of genes implicated in transcription and pluripotency (Oct4, Stat3, Nanog), DNA methylation (Dnmt1, Dnmt3a), histone deacetylation (Hdac2), growth factor signaling, and imprinting (Igf2, Igf2r) and apoptosis (Bax, Bcl2) regulation were observed in NT embryos. The expression of transcripts in MSC-NT embryos more closely followed that of the in vivo derived embryos compared with FF-NT embryos. In conclusion, MSCs with a relatively undifferentiated genome might serve as suitable donors that could be more efficiently reprogrammed to re-activate expression of early embryonic genes in porcine NT.

Effect of cysteamine supplementation of in vitro matured bovine oocytes on chilling sensitivity and development of embryos

In vitro techniques for production of bovine embryos including in vitro oocyte maturation (IVM), fertilization (IVF) and culture (IVC) are becoming increasingly employed for a variety of research purposes. However, decreased viability following cryopreservation by conventional methods has limited commercial applications of these technologies. A practical alternative to facilitate transport would be to arrest development by chilling without freezing. The present research was undertaken to evaluate chilling sensitivity of IVM-IVF embryos at different stages of development, and to determine possible beneficial effects of cysteamine treatment during IVM, previously shown to enhance embryo development in culture, on survival following chilling at different stages. Embryos produced by standard IVM-IVF-IVC methods were chilled to 0 degrees C for 30 min at 2-cell (30-34 h post-insemination, hpi), 8-cell (48-52 hpi) or blastocyst (166-170 hpi) stages. Viability after chilling was assessed by IVC with development to expanded blastocyst stage determined on days 7 and 8 post-insemination (pi) and hatching blastocyst stage determined on days 9 and 10 pi. Control embryos at the same stages were handled similarly, but without chilling, and development during culture similarly assessed. The effect of cysteamine supplementation (100 microM) of the IVM medium was determined for both chilled and non-chilled (control) embryos. Cysteamine supplementation during IVM had no significant effect on oocyte maturation or fertilization, but increased the proportions of oocytes developing to blastocyst stage by day 7 (13.7+/-0.9% versus 7.2+/-0.9%; P<0.05), total blastocysts (20.5+/-0.9% versus 15.3+/-1.3%; P<0.05), and hatching blastocysts (16.8+/-1.6% versus 12.0+/-1.5%; P<0.05). The greater survival in terms of hatching (78.6+/-7.0) following chilling of blastocysts produced by IVM-IVF of oocytes matured in media supplemented with cysteamine offers promise for applications requiring short-term storage to facilitate transport of in vitro produced bovine embryos.

Cellular Composition and Viability of Cloned Bovine Embryos Using Exogene-Transfected Somatic Cells

The present study compared the efficiency of transgenic (TG) cloned embryo production by somatic cell nuclear transfer (SCNT) with fetal-derived fibroblast cells (FFCs) which were transfected with pEGFP-N1 to in vitro-fertilized (IVF), parthenogenetic and SCNT counterparts by evaluating the rates of cleavage and blastocyst formation, apoptosis rate at different developmental stages, cell number, ploidy and gene expression in blastocysts. In SCNT and TG embryos, the rates of cleavage and blastocyst formation were significantly lower (p < 0.05) than those of IVF controls, but it did not differ between SCNT and TG embryos. In IVF control, 86.7% embryos displayed diploid chromosomal complements and the rates were significantly (p < 0.05) higher than those of SCNT and TG embryos. Most TG embryos (79%) with FFCs expressed the gene by both PCR and under fluorescence microscopy. The expression of apoptosis by TUNEL was first detected at six to eight cell stages in all embryos of IVF, SCNT and TG groups, but the expression rate at each developmental stages was significantly higher (p < 0.05) in SCNT and TG embryos than in IVF counterparts. The expression rate in inner cell mass (ICM) of TG embryos was significantly higher (p < 0.05) than in SCNT and IVF embryos. These results indicate that the high occurrence of apoptosis observed in SCNT and TG embryos compared with IVF counterparts might influence the developmental competence. Moreover, the SCNT embryos derived using non-transfected donor cells exhibited a lower apoptosis expression in ICM cells than in TG embryos derived using pEGP-N1-transfected donor cells suggesting a possible role of negative gene effect in TG embryos.