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Research paper thumbnail of Simple synthesis and magnetic properties of nickel-zinc ferrites nanoparticles by using Aloe vera extract solution

Research paper thumbnail of In vitro maturation and fertilization of goat oocytes

Theriogenology, 1992

Follicular cumulus-enclosed goat oocytes were matured in vitro in the presence of granulosa cells... more Follicular cumulus-enclosed goat oocytes were matured in vitro in the presence of granulosa cells, follicle stimulating hormone (FSH), luteinizing hormone (LH) and estradiol-17beta. While 86% of the oocytes from follicles 2 to 6 mm in diameter achieved meiotic maturation, only 24% of the oocytes from follicles 1 to 2 mm in diameter progressed to Metaphase II. Exposure of follicle-enclosed cumulus-oocyte complexes to 20 degrees C prior to culture resulted in 11.5% of the oocytes exhibiting abnormal meiotic spindle. This indicated that immature goat oocytes are particularly sensitive to temperature. Ejaculated spermatozoa were capacitated according to the technique previously proposed for ram sperm (1). The fertilization rates of ovulated and mechanically denuded in vitro-matured oocytes were 85 and 82.8%, respectively; 59.7% of ovulated and 57.1% of in vitro-matured oocytes were normally fertilized, as shown by the presence of both the female and the male pronucleus as well as by the remnants of the sperm tail in the ooplasm, 17 hours after insemination. Polyspermy was the main abnormality detected, and it affected almost 20% of the inseminated oocytes. The cleavage rate (two to fourcell stage) 41 hours after insemination of in vitro-matured and fertilized oocytes was 58%.

Research paper thumbnail of Acoustic-phonetic features for the automatic classification of stop consonants

IEEE Transactions on Speech and Audio Processing, 2001

Research paper thumbnail of The Mu-Opioid Receptor Gene Polymorphism (A118G) Alters HPA Axis Activation Induced by Opioid Receptor Blockade

Neuropsychopharmacology, 2002

An A118G nucleotide exchange in exon 1 of the mu-opioid receptor causes an Asn40Asp substitution ... more An A118G nucleotide exchange in exon 1 of the mu-opioid receptor causes an Asn40Asp substitution polymorphism in the receptor's extracellular domain. In vitro studies show that the Asp40 variant of the mu-opioid receptor binds beta-endorphin three times more avidly than the more common Asn40 variant. Paraventricular corticotropin releasing hormone neurons, which activate the HPA axis, express mu-opioid receptors and are modulated by beta-endorphin neurons. This preliminary study was designed to test the hypothesis that the Asn40Asp substitution polymorphism in the mu-opioid receptor influences HPA axis activation induced by opioid receptor blockade. Thirty-nine healthy men were genotyped (A vs. G) and then underwent opioid receptor blockade with Naloxone. Subjects expressing the A118G receptor variant had greater cortisol responses to opioid receptor blockade. Also, a significant difference in the rate of increase of ACTH (slope) between A/A and A/G was observed between 30-90 minutes as well as a significant difference in the rate of decrease after 90 minutes. Moreover, subjects expressing the variant polymorphism had lower scores on the Conscientiousness Factor and associated subscales of NEO Personality Inventory compared to subjects expressing the common receptor. Because serotonin also modulates the CRF neuron, subjects were genotyped for a functional polymorphism within the serotonin transporter gene. We did not see differences in hormone responses resulting from expression of this functional polymorphism. It is plausible that persons expressing the mu-opioid receptor variant have altered HPA axis dynamics and altered responses to other physiological processes regulated through activation of the mu-opioid receptor.

Research paper thumbnail of Simple synthesis and magnetic properties of nickel-zinc ferrites nanoparticles by using Aloe vera extract solution

Research paper thumbnail of In vitro maturation and fertilization of goat oocytes

Theriogenology, 1992

Follicular cumulus-enclosed goat oocytes were matured in vitro in the presence of granulosa cells... more Follicular cumulus-enclosed goat oocytes were matured in vitro in the presence of granulosa cells, follicle stimulating hormone (FSH), luteinizing hormone (LH) and estradiol-17beta. While 86% of the oocytes from follicles 2 to 6 mm in diameter achieved meiotic maturation, only 24% of the oocytes from follicles 1 to 2 mm in diameter progressed to Metaphase II. Exposure of follicle-enclosed cumulus-oocyte complexes to 20 degrees C prior to culture resulted in 11.5% of the oocytes exhibiting abnormal meiotic spindle. This indicated that immature goat oocytes are particularly sensitive to temperature. Ejaculated spermatozoa were capacitated according to the technique previously proposed for ram sperm (1). The fertilization rates of ovulated and mechanically denuded in vitro-matured oocytes were 85 and 82.8%, respectively; 59.7% of ovulated and 57.1% of in vitro-matured oocytes were normally fertilized, as shown by the presence of both the female and the male pronucleus as well as by the remnants of the sperm tail in the ooplasm, 17 hours after insemination. Polyspermy was the main abnormality detected, and it affected almost 20% of the inseminated oocytes. The cleavage rate (two to fourcell stage) 41 hours after insemination of in vitro-matured and fertilized oocytes was 58%.

Research paper thumbnail of Acoustic-phonetic features for the automatic classification of stop consonants

IEEE Transactions on Speech and Audio Processing, 2001

Research paper thumbnail of The Mu-Opioid Receptor Gene Polymorphism (A118G) Alters HPA Axis Activation Induced by Opioid Receptor Blockade

Neuropsychopharmacology, 2002

An A118G nucleotide exchange in exon 1 of the mu-opioid receptor causes an Asn40Asp substitution ... more An A118G nucleotide exchange in exon 1 of the mu-opioid receptor causes an Asn40Asp substitution polymorphism in the receptor's extracellular domain. In vitro studies show that the Asp40 variant of the mu-opioid receptor binds beta-endorphin three times more avidly than the more common Asn40 variant. Paraventricular corticotropin releasing hormone neurons, which activate the HPA axis, express mu-opioid receptors and are modulated by beta-endorphin neurons. This preliminary study was designed to test the hypothesis that the Asn40Asp substitution polymorphism in the mu-opioid receptor influences HPA axis activation induced by opioid receptor blockade. Thirty-nine healthy men were genotyped (A vs. G) and then underwent opioid receptor blockade with Naloxone. Subjects expressing the A118G receptor variant had greater cortisol responses to opioid receptor blockade. Also, a significant difference in the rate of increase of ACTH (slope) between A/A and A/G was observed between 30-90 minutes as well as a significant difference in the rate of decrease after 90 minutes. Moreover, subjects expressing the variant polymorphism had lower scores on the Conscientiousness Factor and associated subscales of NEO Personality Inventory compared to subjects expressing the common receptor. Because serotonin also modulates the CRF neuron, subjects were genotyped for a functional polymorphism within the serotonin transporter gene. We did not see differences in hormone responses resulting from expression of this functional polymorphism. It is plausible that persons expressing the mu-opioid receptor variant have altered HPA axis dynamics and altered responses to other physiological processes regulated through activation of the mu-opioid receptor.

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