Intermolecular correlations in an ionic liquid under shear

The behavior of a model room temperature ionic liquid under shear is explored using non-equilibrium molecular dynamics simulations. The external field reduces intermolecular structure in the liquid. However, orientational ordering of the molecules in the form of a nematic phase is observed under shear.

2,3,4,9-Tetra-hydro-1H-carbazole

In the title compound, C(12)H(13)N, two methyl-ene C atoms of the cyclo-hexene ring are disordered over two sites with occupancies of 0.591 (10) and 0.409 (10); both disorder components adopt half-chair conformations. The crystal structure is stabilized by inter-molecular N-H⋯π and C-H⋯π inter-actions.

3-Acetyl-4-hydroxyphenyl acrylate. Corrigendum

Corrigendum to Acta Cryst. (2007), E63, o4725.

The chemical name in the title of the paper by Chakkara­varthi, Anthonysamy, Balasubramanian & Manivannan [Acta Cryst. (2007), E63, o4725] is corrected.

Tuberculous gluteal abscess in infancy

Primary tuberculous gluteal abscess without bone involvement has not been reported in infancy. We report 3 infants with isolated tuberculous gluteal abscess who presented with gluteal swelling of 2 weeks, 1 month and 6 months duration, respectively. Tuberculin test was positive in all cases. Pus cultures from the gluteal abscess grew Mycobacterium tuberculosis in all 3 infants.

Tuberculosis associated hemophagocytic syndrome in infancy

An infant presented with prolonged fever, generalized lymphadenopathy, splenohepatomegaly, anemia and seborrheic dermatitis. Investigations including bone marrow findings confirmed the diagnosis of hemo-phagocytic syndrome (HPS) and the infant succumbed. Liver biopsy features of epithelioid granuloma and positive AFB culture of gastric aspirate confirmed the diagnosis of tuberculosis (TB). This rare association of HPS and tuberculosis in infancy is reported.

Synthesis and NMR spectral studies of some 2,6-diarylpiperidin-4-one O-benzyloximes

Variously substituted 2,6-diarylpiperidin-4-one O-benzyloximes were synthesized by the direct condensation of the corresponding 2,6-diarylpiperidin-4-ones with O-benzylhydroxylamine hydrochloride. All the synthesized compounds are characterized by IR, Mass and NMR spectral studies. NMR spectral assignments are made unambiguously by their one-dimensional (1H NMR and 13C NMR) and two-dimensional (1H-1H COSY, NOESY, HSQC and HMBC) NMR spectra. All the synthesized compounds are resulted as single isomer, i.e., exclusively E isomer (9-14). The conformational preference of 2,6-diarylpiperidin-4-one oxime ethers with and without alkyl substituents at C-3 and C-5 has also been discussed using the spectral studies. The observed chemical shifts and coupling constants suggest that compounds 8-13 adopt normal chair conformation with equatorial orientation of all the substituents while compound 14 contributes significant boat conformation along with the predominant chair conformation in solution. The effect of oximination on ring carbons, their associated protons, alkyl substituents and ipso carbons are studied. Every proton in the piperidone ring of the oxime ether is observed as distinct signal due to oximination. The order of chemical shift magnitude in compound 8 is H-2a>H-6a>H-5e>H-3e>H-3a>H-5a. For 9-12, the order is H-6a>H-5e>H-2a>H-3a>H-5a, for 13, H-6a>H-2a>H-5e>H-3a>H-5a and for 14, the order is H-2a>H-6a>H-5e>H-3a>H-5a while the 13C chemical shift magnitude for 8-14 due to oximination is C-2>C-6>C-3>C-5.

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.