Derivation and characterization of embryonic stem-like cells of Indian major carp Catla catla

Embryonic stem (ES)-like cells were derived from mid-blastula stage embryos of a freshwater fish, catla Catla catla, under feeder-free condition and designated as CCES cells. The conditioned media was optimized with 10% foetal bovine serum (FBS), fish embryo extract (FEE) having 100 µg ml(-1) protein concentration, 15 ng ml(-1) basic fibroblast growth factor (bFGF) and basic media containing Leibovitz-15, DMEM with 4·5 g l(-1) glucose and Ham's F12 (LDF) in 2:1:1 ratio using a primary culture of CCES cells. Cells attached to gelatin-coated plates after 24 h of seeding and ES-like colonies were obtained at day 5 onwards. A stable cell culture was obtained after passage 10 and further maintained up to passage 44. These cells were characterized by their typical morphology, high alkaline phosphatase activity, positive expression of cell-surface antigen SSEA-1, transcription factor Oct4, germ cell marker vasa and consistent karyotype up to extended periods. The undifferentiated state was confirmed by their ability to form embryoid bodies and their differentiation potential.

Anomalous suppression of the orthorhombic lattice distortion in superconducting Ba(Fe1-xCox)2As2 single crystals

High-resolution x-ray diffraction measurements reveal an unusually strong response of the lattice to superconductivity in Ba(Fe1-xCox)2As2. The orthorhombic distortion of the lattice is suppressed and, for Co doping near x=0.063, the orthorhombic structure evolves smoothly back to a tetragonal structure. We propose that the coupling between orthorhombicity and superconductivity is indirect and arises due to the magnetoelastic coupling, in the form of emergent nematic order, and the strong competition between magnetism and superconductivity.

Effects of exposure to heavy metals on viability, maturation, fertilization, and embryonic development of buffalo (Bubalus bubalis) oocytes in vitro

The aim of the present study was to examine the effect of heavy metals, cadmium and lead, on buffalo oocyte viability and in vitro development. Oocytes were aspirated from ovaries of slaughtered buffaloes. Only viable and metabolically active oocytes with more than three layers of cumulus cell layers and homogeneous ooplasm were selected. Effects of nine concentrations (0, 0.005, 0.05, 0.5, 1.0, 1.5, 2.5, 5, and 10 microg/mL) of cadmium or lead on buffalo oocyte viability, morphological abnormities, maturation, and embryonic development in vitro were studied. Oocytes were cultured for 24 h and then checked for viability (0.05% trypan blue staining for 2 min), morphological abnormalities, and reduction assay by MTT test in experiment 1. The doses of cadmium and lead causing 100% oocyte death (1-day culture) were determined (experiment 2). In experiment 3, viable oocytes were matured in vitro in media containing different levels of cadmium or lead and then inseminated in vitro with frozen-thawed spermatozoa, and the resultant cleaved embryos were cultured in a control embryo culture medium for 8 days. In experiment 4, oocytes were cultured in control oocyte maturation medium, then fertilized, and the resultant embryos were cultured in media containing different levels of cadmium or lead for 8 days. The number of cells in the trophectoderm and inner cell mass (ICM) and the total cell counts (TCN) of blastocysts derived by in vitro culture of two- to four-cell-stage embryos (produced in control medium) in media containing 0, 0.005, 0.05, 0.5, and 1.0 microg/mL of cadmium or lead were analyzed by differential staining technique (experiment 5). Cadmium and lead were found to have a dose-dependent effect on viability, morphological abnormities, maturation, cleavage and morula/blastocyst yield, and blastocyst hatching. A significant decline in viability of oocytes was observed at 1.0 mg/mL cadmium or lead compared to the control group. The doses of cadmium and lead causing 100% oocyte death (1-day culture) were 18 and 32 microg/mL, respectively. Cadmium and lead at 1.0 and 2.5 microg/mL, respectively, caused a significant reduction of maturation of oocytes compared to the lower concentrations. No cleavage or morulae/blastocysts were produced when the oocytes/embryos were cultured in media containing 2.5 and 5.0 mg/mL of either cadmium or lead, respectively. Similarly, no morulae/blastocysts were produced from cleaved embryos cultured in media containing 2.5 and 5.0 microg/mL cadmium and lead, respectively. The developmental block, degeneration, and asynchronous divisions were higher in embryos exposed to cadmium than in those exposed to lead. TCN and number of cells in ICM were significantly lower in blastocysts derived from two- to four-cell-stage embryos cultured in media containing heavy metals. In conclusion, cadmium and lead lowered the viability and development of buffalo oocytes but at a concentration higher than that estimated in the body fluids and environment. Cadmium was found to be more ovotoxic than lead.

Coexistence of competing antiferromagnetic and superconducting phases in the underdoped Ba(Fe0.953Co0.047)2As2 compound using x-ray and neutron scattering techniques

Neutron and x-ray diffraction studies show that the simultaneous first-order transition to an orthorhombic and antiferromagnetic (AFM) ordered state in BaFe2As2 splits into two transitions with Co doping. For Ba(Fe0.953Co0.047)2As2, a tetragonal-orthorhombic transition occurs at TS=60 K, followed by a second-order transition to AFM order at TN=47 K. Superconductivity occurs in the orthorhombic state below TC=17 K and coexists with AFM. Below TC, the static Fe moment is reduced along with a redistribution of low energy magnetic excitations indicating competition between coexisting superconductivity and AFM order.

Factors affecting laboratory production of buffalo embryos: a meta-analysis

In vitro fertilization (IVF) provides an excellent and inexpensive source of embryos for carrying out basic research on developmental physiology, farm animal breeding, and for commercial applications. Meta-analysis of the results from different publications rather than a narrative review may provide a current status of this technology in buffalo (Bubalus bubalis). In order to gain an idea of the factors affecting the IVF in buffalo, a review of the various studies conducted on buffalo IVF and a meta-analysis of their findings was undertaken. More than 100 articles published from 1991 to 2008 were searched, and results were subjected to meta-analysis to determine the treatment variations without any bias. Thirty factors affecting in vitro embryo production in buffalo were considered. Initially, both fixed- and random-effect models were used. We did not observe any heterogeneity between the studies. Thereafter, all the studies were pooled using the fixed-effect model for analysis. Our analysis suggested that good buffalo oocytes with more than three to five cumulus layers recovered from large-sized follicles in cold seasons when cultured in TCM-199 supplemented with serum, follicle-stimulating hormone, and cysteamine resulted in maximum maturation rate and subsequent embryonic development after insemination. The values obtained in the current study may be considered for a simulation model in establishing a cost-effective suitable method for buffalo IVF in further planned research.

Nonexponential London penetration depth of FeAs-based superconducting RFeAsO(0.9)F(0.1) (R = La, Nd) single crystals

The superconducting penetration depth lambda(T) has been measured in RFeAsO(0.9)F(0.1) (R = La, Nd) single crystals (R-1111). In Nd-1111, we find an upturn in lambda(T) upon cooling and attribute it to the paramagnetism of the Nd ions, similar to the case of the electron-doped cuprate Nd-Ce-Cu-O. After the correction for paramagnetism, the London penetration depth variation is found to follow a power-law behavior, Deltalambda_{L}(T) proportional, variantT;{2} at low temperatures. The same T2 variation of lambda(T) was found in nonmagnetic La-1111 crystals. Analysis of the superfluid density and of penetration depth anisotropy over the full temperature range is consistent with two-gap superconductivity. Based on this and on our previous work, we conclude that both the RFeAsO (1111) and BaFe(2)As(2) (122) families of pnictide superconductors exhibit unconventional two-gap superconductivity.

Unconventional London penetration depth in single-crystal Ba(Fe0.93Co0.07)2As2 superconductors

The London penetration depth lambda(T) has been measured in single crystals of Ba(Fe0.93Co0.07)2As2. The observed low-temperature variation of lambda(T) follows a power law, Deltalambda(T) approximately T(n) with n approximately 2.4+/-0.1, indicating the existence of normal quasiparticles down to at least 0.02T(c). This is in contrast with previous penetration depth measurements on single crystals of NdFeAsO1-xFx and SmFeAsO1-xFx, which indicate an anisotropic but nodeless gap. We discuss possible explanations of the observed power law behavior.

Anisotropic three-dimensional magnetism in CaFe2As2

Inelastic neutron scattering measurements of the magnetic excitations in CaFe2As2 indicate that the spin wave velocity in the Fe layers is exceptionally large and similar in magnitude to the cuprates. However, the spin wave velocity perpendicular to the layers is at least half as large that in the layer, so that the magnetism is more appropriately categorized as anisotropic three-dimensional, in contrast to the two-dimensional cuprates. Exchange constants derived from band structure calculations predict spin wave velocities that are consistent with the experimental data.

Viability and growth of buffalo preantral follicles and their corresponding oocytes in vitro: effect of growth factors and beta mercaptoethanol

The present study was undertaken to isolate buffalo preantral follicles (PFs), to test the viability and sizes of buffalo PFs and to examine the effect of various growth factors (insulin-like growth factor, fibroblast growth factor) and an antioxidant (beta mercaptoethanol) on the in vitro growth, survival and antrum formation rates of buffalo PFs and growth rates of oocytes in cultured PFs. Preantral follicles from slaughtered buffalo ovaries were recovered by a combined mechanical and enzymatic method. The recovery rates of >40-100, 101-200, 201-300, 301-400 and 401-500 microm PFs were 5.1, 3.2, 3.1, 6.3 and 5.1 per ovary, respectively. The corresponding viability rates were 76.1%, 78.1%, 85.2%, 92.5% and 92.6%, respectively. There was a positive correlation (r = 0.73) between oocyte size and the follicular size. However, there was no significant correlation between the size of oocyte and its viability at the time of its retrieval from ovary. Insulin-like growth factor and fibroblast growth factor improved the survival of buffalo PFs and regulated their growth in culture. The growth factors and beta mercaptoethanol in association synergically improved the growth and survival of buffalo PFs.

Biodistribution of an oncolytic adenovirus after intracranial injection in permissive animals: a comparative study of Syrian hamsters and cotton rats

Conditionally replicative adenoviruses (CRAds) are often evaluated in mice; however, normal and cancerous mouse tissues are poorly permissive for human CRAds. As the cotton rat (CR) is a semipermissive animal and the Syrian hamster (SH) is a fully permissive model for adenoviral replication, we compared them in a single study following intracranial (i.c.) injection of a novel glioma-targeting CRAd. Viral genomic copies were quantified by real-time PCR in brain, blood, liver and lung. The studies were corroborated by immunohistochemical, serological and immunological assays. CR had a multiple log higher susceptibility for adenoviral infection than SH. A similar amount of genomic copies of CRAd-Survivin-pk7 and human adenovirus serotype 5 (AdWT) was found in the brain of CR and in all organs from SH. In blood and lung of CR, AdWT had more genomic copies than CRAd-Survivin-pk7 in some of the time points studied. Viral antigens were confirmed in brain slices, an elevation of serum transaminases was observed in both models, and an increase in anti-adenoviral antibodies was detected in SH sera. In conclusion, CR represents a sensitive model for studying biodistribution of CRAds after i.c. delivery, allowing for the detection of differences in the replication of CRAd-Survivin-pk7 and AdWT that were not evident in SH.

Effect of a partially purified 30.1 kDa ovine follicular fluid protein on ovine follicle and ovarian somatic cell growth, and oocyte maturation in vitro

AIM

Regulation of folliculogenesis and oocyte-somatic cell interactions in the ovarian follicles is under the control of gonadotrophins and various local factors. In the present study, an attempt was made to isolate and examine the biological activities of ovarian follicular fluid protein(s) in sheep in vitro.

METHODS

Follicular fluids aspirated from ovarian follicles of slaughterhouse-derived ovaries were made cell free by centrifugation (5000 g for 30 min) and steroid free by charcoal treatment. The follicular fluid was then subjected to ammonium sulphate precipitation and gel filtration chromatography using G-75 Sephadex. Protein detection was performed using a UV spectrophotometer at 280 nm. The 35-50% fraction yielded a detectable peak and a protein of 30.1 kDa as examined by SDS-PAGE. The effect of increasing doses of the 30.1 kDa ovine follicular fluid protein (oFFP) was tested at different doses on pre-antral and antral follicle growth; cumulus cell expansion; oocyte maturation; changes in protein, calcium and phosphorus levels of oocytes after culture in media containing different levels of isolated protein; mural granulosa cell, polar granulosa cell (cumulus cell), oviductal epithelial cell monolayer formation and granulosa cell proliferation in vitro.

RESULTS

The oFFP significantly inhibited antral follicle growth, cumulus expansion, oocyte maturation and somatic cell growth in vitro in a dose-dependent manner. The oFFP did not have a significant effect on the pre-antral follicle growth in vitro. The protein, calcium and phosphorus contents of oocytes were found to decrease in oocytes cultured in maturation medium containing the oFFP.

CONCLUSION

The present study demonstrates a follicular fluid factor regulating folliculogenesis and oocyte maturation in sheep.

Nature of Ho magnetism in multiferroic HoMnO3

Using x-ray resonant magnetic scattering and x-ray magnetic circular dichroism, techniques that are element specific, we have elucidated the role of Ho3+ in multiferroic HoMnO3. In zero field, Ho3+ orders antiferromagnetically with moments aligned along the hexagonal c direction below 40 K, and undergoes a transition to another magnetic structure below 4.5 K. In applied electric fields of up to 1 x 10(7) V/m, the magnetic structure of Ho3+ remains unchanged.

Effect of taurine and melatonin in the culture medium on buffalo in vitro embryo development

This study was carried out to investigate the effect of supplementing culture medium with different concentrations of taurine and melatonin, on buffalo oocyte in vitro meiotic maturation and embryo development. In experiment 1, oocytes were matured in vitro and the cleaved embryos were cultured in the same following seven culture medium; (i) control (TCM 199 + 10% SS); (ii) control + 0.5 mM taurine; (iii) control + 1 mM taurine; (iv) control + 3 mM taurine; (v) control + 5 microM melatonin; (vi) control + 10 microM melatonin and (vii) control + 50 microM melatonin. In experiment 2, based on the results of experiment 1, to examine the synergistic effect of antioxidants, the oocytes were matured in culture medium (TCM199 + 10% SS), supplemented with both taurine at 1 mM and melatonin at 10 microM concentration and the cleaved embryos were cultured in the same medium. Supplementation of taurine at 1 mM concentration in the culture medium resulted in a higher (p < 0.05) transferable embryo (TE) yield when compared with control (20.6% vs 14.1%). Supplementation of melatonin at 10 and 50 microM concentration in the culture medium resulted in a higher (p < 0.05) meiotic maturation rate (90.3% and 88.8% respectively) and TE yield (28.4% and 27.2% respectively), than the other treatments. In experiment 2, the TE yield did not improve by supplementing the culture medium with both taurine and melatonin, when compared with melatonin alone. In conclusion, the results of this study demonstrated that, enriching the culture medium with taurine and melatonin, improves in vitro embryo production efficiency in buffaloes. In particular, a high TE yield was obtained by enriching the culture medium with 10 microM melatonin.

Effect of breeding season on in vivo oocyte recovery and embryo production in non-descriptive Indian river buffaloes (Bubalus bubalis)

The present study was carried out to examine the effect of season on in vivo oocyte recovery and embryo production in non-descriptive, Indian river buffaloes (Bubalus bubalis). Ovum pick up (OPU) was conducted twice a week for 8 weeks during peak (October-March) and low (April-September) breeding season in live buffaloes (n=6). OPU was performed using ultrasound equipment with a 5MHz transvaginal transducer, a single lumen 18-gauge, 55-cm long needle and a constant vacuum pressure of 110mmHg. The number and size of follicles was determined before puncture. The recovered oocytes were graded and only grade A and grade B oocytes were used for in vitro production (IVP) of embryos. The mean number of follicles observed per animal per session did not differed (P<0.05) between animals or between puncture sessions in both low and peak breeding seasons. Higher (P<0.05) number of follicles were observed (4.8+/-0.2 versus 3.1+/-0.3) and punctured (4.0+/-0.2 versus 2.4+/-0.2) during peak breeding season when compared to low breeding season. Oocytes recovered (1.6+/-0.1 versus 1.0+/-0.3) per animal per session were higher (P<0.05) in peak breeding season than low breeding season. During the peak breeding season, the blastocyst yield per animal per session (0.3+/-0.4 versus 0.18+/-0.4) was higher (P<0.05) than the low breeding season. However, season did not significantly affect the percentage of oocytes suitable for IVP (grade A+B) and blastocyst production rate. In conclusion, the efficiency of OPU combined with IVP was higher during the peak breeding season than the low breeding season in buffaloes.

In vitro embryo development and blastocyst hatching rates following vitrification of river buffalo embryos produced from oocytes recovered from slaughterhouse ovaries or live animals by ovum pick-up

The present study was undertaken to determine whether the source of oocytes (ovum pick up versus slaughterhouse ovaries) affected in vitro embryo production and embryo survival (as measured by blastocyst hatching rates) following vitrification in buffaloes (Bubalus bubalis). Oocytes recovered from live buffaloes (n=6) by ovum pick up (OPU) and by manual aspiration from slaughterhouse ovaries were in vitro matured, fertilized and cultured to blastocyst stage under same culture conditions. Vitrification of blastocysts was carried out in two steps at 24 degrees C. Embryos were equilibrated in 10% EG+10% DMSO+0.3 M sucrose in base medium for 4 min. Subsequently, the embryos were transferred into 25% EG+25% DMSO+0.3 M sucrose in base medium for 45 s and then the embryos were loaded into straws and immersed in liquid nitrogen. Following warming, blastocysts were cultured in vitro for 48 h to assess hatching. Oocytes derived from live animals by OPU resulted in a significantly higher blastocyst yield then those derived from slaughterhouse ovaries (30.6+/-4.3 versus 18.5+/-1.8). Blastocyst hatching rates following vitrification of buffalo embryos produced from the oocytes collected from live animals by OPU was significantly higher than the oocytes collected from slaughterhouse ovaries (52.8+/-4.2 versus 40.2+/-4.4). In conclusion, the present study showed that source of oocytes (OPU versus slaughterhouse ovaries) affects the in vitro embryo development and blastocyst hatching rates following vitrification of embryos in buffaloes.

Co-culture of buffalo preantral follicles with different somatic cells

The effect of co-culture of buffalo preantral follicles (PFs) with different somatic cells, i.e, cumulus, granulosa, ovarian mesenchymal and oviductal epithelial cells was studied. Large PFs (250-450 microm) were isolated by microdissecting the trypsin (1%) digested ovarian cortical slices. Cumulus cells were isolated by repeated pipetting of oocytes, granulosa cells were isolated by aspirating from punctured PFs and ovarian mesenchymal cells were isolated from ovarian cortex by scraping the cortical slices and passing through 20 microm filter. Preantral follicles were cultured in standard culture medium without somatic cells or co-cultured with cumulus cells, granulosa cells, ovarian mesenchymal cells and oviductal epithelial cells for 80 days. The growth rate (microm/day) of the PFs was monitored by measuring follicular diameter on day 0, 30, 60 and 80 days of culture. The viability of PFs was evaluated by trypan blue staining. The results indicated that PFs co-cultured with cumulus, granulosa and ovarian mesenchymal cells had a better development and survivality compared with control and those co-culture with oviductal epithelial cells. Maximum growth and survivality of PFs were achieved when cultured with cumulus cells. It is concluded that inclusion of somatic cells in PF culture media had beneficial effect on the growth of PFs and cumulus cells supported maximum growth and survivality of PFs in vitro of all somatic cells tested.