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.

Selection of developmentally competent buffalo oocytes by brilliant cresyl blue staining before IVM

The brilliant cresyl blue (BCB) test determines the activity of glucose-6-phosphate dehydrogenase (G6PDH); the activity of this enzyme is greatest in growing oocytes, but it declines as oocytes mature. The objective was to develop and evaluate this test for assessing development of buffalo oocytes (to select developmentally competent oocytes for increased in vitro embryo production). Oocytes were exposed to BCB stain diluted in mDPBS (DPBS with 0.4% BSA) for 90 min at 38.5 degrees C in a humidified air atmosphere; those with or without blue coloration of the cytoplasm were designated as BCB+ and BCB-, respectively. In Experiment 1, oocytes were exposed to 13, 26, or 39 microM BCB. There were fewer BCB+ oocytes after exposure to 13 microM BCB (10%) than after exposure to 26 or 39 microM BCB (57.2 and 61.8%; P<0.05), but there was no significant difference among treatments for blastocyst production rate. In Experiment 2, the diameter of BCB+ oocytes (144.4+/-4.2 microm; mean+/-S.E.M.) was higher (P<0.05) than that of BCB- oocytes (136.8+/-4.6 microm). In Experiment 3, oocytes were allocated into three groups: control (immediately cultured); holding-control (kept in mDPBS for 90 min before cultured); and treatment-incubation (incubated with 26 microM BCB). After IVM, oocytes were fertilized in vitro and cultured on an oviductal monolayer. The nuclear maturation rate was higher (P<0.05) in BCB+ (86.2%), control (83.4%) and holding-control (82.6%) oocytes than BCB- (59.2%) oocytes. The BCB+ oocytes yielded more blastocysts than control or holding-control oocytes (33.4, 20.2, and 21.0%, P<0.05); blastocyst development was lowest in BCB- oocytes (5.2%). In conclusion, staining of buffalo oocytes with BCB before IVM may be used to select developmentally competent oocytes for increased in vitro embryo production.

Recovery of large preantral follicles from buffalo ovary: Effect of season and corpus luteum

Preantral follicle can be considered as an alternative source of oocyte for in vitro production of embryos. The objective of the present study was to standardize a procedure for the isolation of large preantral follicles (>150-500 microm) from buffalo ovaries and to determine the effect of season and the presence of corpus luteum on the recovery rate of the large preantral follicles. A combined enzymatic cum mechanical approach was adopted to recover the large preantral follicles. In the first experiment, the ovarian cortical pieces were suspended in trypsin (1000-1500 BAEE units for milligrams of solid) and incubated at various temperatures for different periods, i.e. (1) trypsin (1%), 37 degrees C for 10 min; (2) trypsin (1%), 37 degrees C for 10 min + 4 degrees C for 3 h; (3) trypsin (0.5%), 37 degrees C for 20 min; (4) trypsin (0.25%), 37 degrees C for 20 min. Although there was no significant difference (P>0.05) among the different protocols, the first protocol yielded more follicles (3.2, 2.6, 1.8 and 1.5 per ovary, respectively). Hence, the first protocol was selected and used in the second and third experiments. In the second experiment, the effect of season, i.e. peak breeding season (October-March) versus low breeding season (April-September) was evaluated on the recovery rate of the large preantral follicles. The recovery rate of large preantral follicles from the ovaries during the peak breeding season was significantly (P<0.05) greater (9.92+/-0.85 per ovary) than that of the low breeding season (4.95+/-0.27 per ovary). In the third experiment, effect of the presence of corpus luteum on the recovery rate of large preantral follicles was studied. There was a significantly (P<0.05) higher yield of large preantral follicles from the ovaries with corpus luteum (8.05+/-0.88 per ovary) than for the ovaries without corpus luteum (4.57+/-0.43 per ovary). This study confirms that the large preantral follicles can be isolated from buffalo ovaries using a combination of enzymatic cum mechanical methods and that more large preantral follicles can be recovered during the peak breeding season and from the ovaries having corpus luteum.

In vitro developmental competence of buffalo oocytes collected at various stages of the estrous cycle

The objective was to determine the in vitro developmental competence of buffalo oocytes collected from abattoir-derived ovaries at various stages of the estrous cycle and follicular status. In Experiment 1, ovaries (n=476 pairs) were collected and divided into the following five groups: (a) ovaries with a corpus hemorragicum and no dominant follicle (CH-NO-DF); (b) ovaries with a mature functional corpus luteum (CL) and a dominant follicle (CL-DF); (c) ovaries with a mature functional CL and no dominant follicle (CL-NO-DF); (d) ovaries with a regressing CL and a dominant follicle (RCL-DF); and (e) ovaries without any luteal structures and only small follicles (ANEST). In Experiment 2, 144 pairs of ovaries with a CL (or regressing CL) and a dominant follicle were collected and follicles were classified as dominant, largest subordinate, and subordinate. In both experiments, the dominant follicle was defined as any follicle >10mm in diameter that exceeded the diameter of all other (subordinate) follicles. Although oocytes were collected from each group of ovaries, only Grades A or B oocytes were used for in vitro embryo production. Cleavage rates were higher (P<0.05) from oocytes collected from ovaries in the CH-NO-DF (59.6%) and CL-NO-DF (59.2%) groups than those collected from CL-DF (52.2%) and ANEST (43.6%) groups. The yield of transferable embryos was higher (P<0.05) from oocytes collected from CH-NO-DF (27.4%) and CL-NO-DF (24.0%) ovaries than from CL-DF (16.2%), RCL-DF (15.4%), and lowest (P<0.05) from ANEST (8.8%). In Experiment 2, oocytes from the dominant follicle had a higher (P<0.05) cleavage rate (65.2 %) and transferable embryo yield (30.2%) than those collected from the largest subordinate and subordinate follicles. In conclusion, oocyte competence depended on the morphofunctional state of ovaries. Oocyte development was maximal in pairs of ovaries with a corpus hemorragicum or CL and no dominant follicle; in paired ovaries with a CL and a dominant follicle, development was maximal in oocytes derived from the dominant follicle.

Biochemical composition of ovine follicular fluid in relation to follicle size

The aim of this study was to biochemically characterize ovine follicular fluid and to relate possible changes in composition to follicular size. Ovaries were collected from adult and cycling non-pregnant slaughtered sheep (Ovis aries) during breeding season. A total of 104 pairs of ovaries were investigated and these data were then compared. Follicular fluid was aspirated from small (< 2 mm), medium (2-4 mm) and large (> 4 mm) nonatretic ovarian follicles. The follicular fluid was centrifuged at 4 degrees C and 5000 g for 30 min to remove any cells and stored at -80 degrees C prior to assay. Follicular fluid samples were analyzed for glucose, total protein, cholesterol, triglycerides, lactate, urea, creatinine, sodium, potassium, chloride, calcium, phosphorus, magnesium, acid phosphatase, alkaline phosphatase, and lactate dehydrogenase. Data were analyzed by the linear regression model. As follicles became larger, the concentrations of glucose and cholesterol significantly (P < 0.05) increased while those of triglycerides, lactate, alkaline phosphatase and lactate dehydrogenase significantly (P < 0.05) decreased.

Effect of ovine follicular fluid peptide on ovarian responses and other organ weights in rats, Rattus norvegicus Berkenhout 1769

The present study was aimed to study the effect of an ovine follicular fluid peptide on ovarian follicle and good oocyte numbers and weights of ovary, uterus, liver, pancreas and kidney in rats, R. norvegicus. A 30.1 kDa peptide was isolated from ovine follicular fluid by ammonium sulphate precipitation and then gel filtration. The peptide was tested at various levels in normal (22 and 36 day-old), superovulated (29 day-old) immature and 121-day old mature rats on the ovarian responses and other organ weights. The isolated peptide inhibited the growth of antral follicles in normal and superovulated rats. Ovarian, uterine weight and recovery of good oocytes were reduced when the peptide was administered at 100 microg dose. The peptide had no effect on kidney, liver, pancreas weight and recovery of preantral follicles.

Phosphorylation of MCT-1 by p44/42 MAPK is required for its stabilization in response to DNA damage

We discovered a novel oncogene in a T-cell lymphoma cell line, multiple copies in T-cell lymphoma-1 (MCT-1), that has been shown to decrease cell-doubling time, shorten the duration of G(1) transit time and/or G(1)-S transition, and transform NIH3T3 fibroblasts. We subsequently demonstrated that there were significantly increased levels of MCT-1 protein in a subset of primary diffuse large B-cell lymphomas. Levels of MCT-1 protein were shown to be increased after exposure to DNA damaging agents. This increase did not require new protein synthesis, suggesting that post-translational mechanisms were involved. Phosphorylation is one potential mechanism by which the activity of molecules involved in cell cycle/survival is rapidly modulated. The RAS/mitogen-activated/extracellular-regulated kinase (MEK)/extracellular signal-regulated kinases (ERK) pathway plays a prominent role in the regulation of cell growth and proliferation through phosphorylation-dependent regulation of several substrates. The MCT-1 protein is predicted to have numerous putative phosphorylation sites. Using a combination of genetic and pharmacological approaches, we established that phosphorylation of MCT-1 protein by p44/p42 mitogen-activated protein kinases is critical for stabilization of MCT-1 protein and for its ability to promote cell proliferation. Our data suggests that targeting the RAS/MEK/ERK signal transduction cascade may provide a potential therapeutic approach in lymphomas and related malignancies that exhibit high levels of MCT-1 protein.

RNA interference: potential therapeutic targets

One of the most exciting findings in recent years has been the discovery of RNA interference (RNAi). RNAi methodologies hold the promise to selectively inhibit gene expression in mammals. RNAi is an innate cellular process activated when a double-stranded RNA (dsRNA) molecule of greater than 19 duplex nucleotides enters the cell, causing the degradation of not only the invading dsRNA molecule, but also single-stranded (ssRNAs) RNAs of identical sequences, including endogenous mRNAs. The use of RNAi for genetic-based therapies has been widely studied, especially in viral infections, cancers, and inherited genetic disorders. As such, RNAi technology is a potentially useful method to develop highly specific dsRNA-based gene-silencing therapeutics.

Molecular heterogeneity among north Indian isolates of Group A Streptococcus

AIM

To monitor molecular heterogeneity among the clinical isolates of group A Streptococcus (GAS) from north India by Vir and emm typing.

METHODS AND RESULTS

GAS isolates, 31 from pharyngitis and nine from rheumatic fever (RF)/rheumatic heart disease (RHD) patients were differentiated into 16 Vir types (VT). These isolates were further discriminated into 23 emm types. Most of emm types were Vir type specific, except few (7.5%), which revealed different Vir types within same emm type. The most prevalent emm type found was emm 49 (15%) followed by 7.5% of emm 69, emm 71 and emm 75 which were different from emm type distribution reported from south India.

CONCLUSIONS

Analysis of data revealed 40% heterogeneity by Vir typing and 57.5% by emm typing among GAS isolates which is significant in view of small number of isolates studied. SIGNIFICANCE OF IMPACT OF THE STUDY: The molecular study for the first time demonstrates different emm types prevalent and circulating in northern region of India and such data may help in selection of types for vaccine development.

In vitro Development of Buffalo Oocytes in Media-containing Fluids from Different Size Class Follicles

Studies were conducted to investigate the effect of supplementation of fluid from different sized class [small (SFF, < 3 mm), medium (MFF, 3-8 mm) and large (LFF, > 8 mm)] of normal and cystic (CFF) ovarian follicles in oocyte culture media on oocyte maturation rate and embryo development in vitro and to test the efficacy of follicular fluid (FF) from different size classes as a whole oocyte maturation medium. Results suggested that FF were capable of developing buffalo oocytes to embryonic stage in vitro although its efficacy was lower than that of serum. Regardless of high maturation rates after in vitro maturation (IVM) in media containing FF or IVM in whole FF, low blastocyst rates were obtained after in vitro fertilization (IVF) and culture of embryos. Follicular fluid from small follicles had significantly (p < 0.05) higher potential of developing buffalo oocytes to embryonic stage in vitro than that from medium and large follicles. Cystic FF was not capable of supporting development of buffalo oocytes in vitro.

A Vero cell-attenuated Goatpox virus provides protection against virulent virus challenge

An Indian isolate of Goatpox virus (GTPV) was adapted and propagated in Vero cells for development of an attenuated virus. The virus was initially passaged in primary lamb testes cells and subsequently in Vero cells. At the 55th passage, the virus showed evidence of attenuation when tested for safety in seronegative goats. At this stage, the virus was found to be completely non-pathogenic. The virus was passaged further and the 60th passage was used for testing its immunogenicity in goats. The latter were inoculated with 10, 100 and 1000 TCID50 of the attenuated virus by intradermal (i.d.) route and challenged after 28 days with virulent GTPV. The attenuated virus produced no adverse reaction even at the highest dose and conferred complete protection even at the lowest dose against challenge with a high dose (2 x 10(6) of 50% skin-reactive dose SRD50) of virulent virus. Increased levels of virus-specific serum antibodies could be demonstrated by both indirect enzyme-linked immunosorbent assay (ELISA) and virus neutralization (VN) test in all the immunized goats. No horizontal transmission of the virus from the immunized to in-contact animals took place. Our results suggest that this attenuated virus could be a safe, immunogenic and potent candidate for developing a vaccine against goatpox.