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J Sosnowski

Publications and source records attributed to J Sosnowski.

12 recordsLinked to original sources
PubMed1998

Cytogenetic analysis of bovine parthenotes after spontaneous activation in vitro.

We conducted a cytogenetic study of bovine parthenotes derived from oocytes matured and cultured in vitro. In vitro maturation was carried out by culturing follicular oocytes for 24 h in TCM199 supplemented with estrous cow serum (ECS) and hormones at 39 degrees C in 5% CO2. Matured oocytes were incubated for 20 h in sperm TALP without the addition of spermatozoa, after which they were cultured in maturation droplets for 48 to 72 h. Spontaneous activation occurred in 9.5% of the matured oocytes. Cytogenetic analysis of 24 parthenotes revealed that 62.5% exhibited a normal, diploid chromosome complement. The remaining 37.5% had various ploidy anomalies: haploidy (25%), triploidy (4.2%) and tetraploidy (8.3%). Parthenotes exhibited different developmental stages. The number of blastomeres ranged from 2 to 8 within a parthenote. Only 1 parthenote was comprised 9 to 16 cells. The results showed that spontaneous parthenogenetic activation which occurs in an IVM/IVF system may interfere with embryo production efficiency.

Animals↗
PubMed1997

Cytogenetic analysis of horse oocytes matured in vitro for different periods of time.

This paper presents the results of recovering horse oocytes by aspiration and maturation in vitro for 24, 30, 36 or 42 h. A total of 522 oocytes were recovered from 221 ovaries (2.4 per ovary) and 271 oocytes (51.9%) were selected for in vitro maturation (IVM). Oocytes were cultured in maturation medium (TCM 199 + estrus cow serum [ECS] + follicle-stimulating hormone [FSH] + 17 beta-estradiol + gentamycin). One hundred and seventy oocytes were cytogenetically analysed (68.3%). Cytogenetic analysis showed that the stage of maturation (first telophase-TI or second metaphase-MII) for fertilization was achieved in 42.2% of oocytes after 24 h, 70.4% of oocytes after 30 h, 75.0% of oocytes after 36 h and 74.4% of oocytes after 42 h of in vitro maturation.

Animals↗
PubMed1997

Protein kinase C mediated anti-proliferative glucocorticoid-sphinganine synergism in cultured Pollard III prostate tumor cells.

PURPOSE: Experimental effort focused on the growth inhibition of an androgen-resistant prostatic carcinoma, using pharmacological inhibition of protein kinase C (PKC) as the therapeutic target. MATERIALS AND METHODS: Studies were performed in cell culture using the Pollard (PA) III androgen-insensitive spontaneous rat prostate tumor cells, and the human prostate tumor lines, PC-3 and LnCaP. Pharmacological agents included steroid hormones and PKC modulators; measured parameters of tumor growth/function included cell number, PKC activity and sphingolipid metabolism. RESULTS: Triamcinolone (TA) and sphinganine synergized to inhibit the proliferation rate of PA III prostate tumor cells by converging through separate mechanisms to inhibit protein kinase C. At five days of cell culture, 0.1 microM TA reduced both the soluble and particulate forms of PKC in association with a 35-40% reduction in cellular proliferation. Exogenous sphinganine, a competitive inhibitor at the regulatory domain of PKC had no anti-proliferative effect at 1 microM, but in combination with TA synergized to reduce proliferation 80-90%, three days in advance of any detectable inhibitory effect of TA alone on cell number. TA produced no discernable stimulation of endogenous free sphingosine production as evidenced by the lack of an effect on the activity of neutral membrane sphingomyelinase or in the turnover of total cellular sphingomyelin. Phorbol esters, but not cell permeable diglycerides, prevented the TA + sphinganine effect suggesting that a stable long term PKC activation was required for reversal. Steroid specificity studies of the synergistic response revealed that while other glucocorticoids mimicked TA, aldosterone was less active and representatives of the three major classes of sex steroids were inert. Tests of sphinganine specificity demonstrated that calphostin C, a chemically unrelated inhibitor of the regulatory site of PKC, also produced a supra-additive interaction with TA. Ceramides (C2 & C6), which were closely related chemically to sphinganine but lacked affinity for the regulatory subunit of PKC, were inactive in this system. Analyses of the cellular specificity of the TA-sphinganine synergism using the human prostate carcinoma cell lines PC-3 and LnCap revealed a true synergistic growth inhibition in the glucocorticoid receptor positive PC-3 line and no significant interaction in the glucocorticoid receptor negative LnCap cells. CONCLUSIONS: TA-induced reduction of PKC concentration coupled with sphinganine antagonism of PKC activation contributed to in a synergistic growth inhibition of an androgen resistant prostatic carcinoma.

Animals↗
PubMed1996

Cytogenetic evaluation of in vitro matured bovine oocytes collected from ovaries of individual donors.

Oocytes were collected after slaughter by aspiration from pairs of ovaries of individual donors. A total of 656 oocytes was selected for IVM from 74 pairs of ovaries (8.9 oocytes per pair, ranging between 1 and 25). The oocytes were matured in droplets of maturation medium (TCM-199 medium supplemented with 20% estrous cow serum (ECS), 50 microg/ml gentamycin, 10 microg/ml FSH, 1 microg/ml estradiol-17beta). Cytogenetic analysis of 348 oocytes showed 79 at the first metaphase (MI; 22.7%, 79 348 ), 11 at the first telophase (TI; 3.2%, 11/348 ), and 258 at the second metaphase (MII; 74.1% 258/348 ). Significant differences (P < 0.01) were shown among the donors regarding the number of oocytes selected for IVM and the number of oocytes matured for IVF.

Journal Article↗
PubMed1996

Efficacy of selection criteria for ovarian reserve screening using the clomiphene citrate challenge test in a tertiary fertility center population.

OBJECTIVE: To examine selection criteria for ovarian reserve screening. DESIGN: Retrospective study. PATIENTS: Two hundred nineteen women underwent testing for ovarian reserve for woman's age > 35 years, any age with unexplained infertility, one ovary, or a poor response to hMG. INTERVENTIONS: Clomiphene citrate challenge test. MAIN OUTCOME MEASURES: Frequency of abnormal ovarian reserve screening, menstrual cycle parameters, response to hMG, and pregnancy outcome by screening criteria. RESULTS: One hundred eighty-four (84.0%) women had a normal ovarian reserve screening test; 35 (16.0%) had an abnormal ovarian reserve screening test. Twenty-six had abnormal ovarian reserve screening when screened by age, 14 for unexplained infertility, 5 for poor response to hMG, and 6 for one ovary. Fifteen women with abnormal ovarian reserve screening had more than one indication for screening. For women attempting pregnancy (n = 182), 49 of 148 (33.1%) with normal ovarian reserve screening became pregnant compared with 2 of 34 (5.9%) with abnormal ovarian reserve screening. Within each screening category, women with abnormal ovarian reserve had menstrual cycle parameters associated with a short follicular phase, required more hMG, and responded poorly to hMG. CONCLUSIONS: One of six women undergoing ovarian reserve screening had an abnormal test, which was associated a poor reproductive outcome. Age was the most important single criteria. Selected ovarian reserve screening is simple and inexpensive and should be offered to all fertility patients meeting the specific screening criteria listed above.

Adult↗
PubMed1992

Immunotherapy of murine transitional cell carcinoma of the bladder using alpha and gamma interferon in combination with other forms of immunotherapy.

BCG immunotherapy is very effective in the treatment of superficial transitional cell carcinoma of the bladder, but its significant toxicity may limit its use in some patients. In an effort to find less toxic and potentially more effective treatments we investigated the possible immunotherapeutic potential of combinations of Alpha Interferon (1000 IU) and Gamma Interferon (500 IU) with bacillus Calmette Guerin (BCG) (10(7) cfu), Interleukin-2 (4000 IU), and Keyhole Limpet Hemocyanin (50 micrograms.) in the MBT2 murine bladder cancer model. Significant reductions (p less than 0.05) in tumor incidence relative to the saline control, 83%, Day 35) was observed in groups receiving alpha interferon (42%), Keyhole limpet hemocyanin (42%), interleukin-2 (25%), alpha interferon + Keyhole limpet hemocyanin (17%), alpha interferon + interleukin-2 (33%), gamma interferon + BCG (42%), and gamma interferon + interleukin-2 (17%). All treatment groups with the exception of the group receiving gamma interferon had significantly reduced tumor volume (p less than 0.05) relative to the saline control. Combination treatment groups were significantly more effective than single agent treatments (p = 0.0057). The exhibited anti-tumor effect of these immunotherapeutic agents alone and in combination suggest that they may prove to be effective forms of immunotherapy for transitional cell carcinoma of the bladder.

Animals↗
PubMed1987

Pathologic effects of ESWL on canine renal tissue.

The introduction of extracorporeal shock wave lithotripsy (ESWL) has provided an avenue for dealing with many urinary stones noninvasively. The margin of safety for the kidney during shock wave administration is largely undefined. A pilot study was performed where six kidneys in five female mongrel dogs were shocked. Group A kidneys were given 1,776, 4,500, 6,000, or 8,000 shocks, respectively, at 18-24 kV. Group B kidneys received 1,600 and 8,000 shocks (18-24 kV). The number of shocks per electrode ranged from 500 to 4,538 and averaged 2,490. The dogs were sacrificed forty-eight to seventy-two hours (Group A) or twenty-eight to thirty-two days (Group B) post-treatment. Modest damage (hematoma and/or interstitial hemorrhage) was noted in all kidneys. Evidence of permanent change (fibrosis) was noted in both Group B kidneys. Complete necrosis of the kidney was not seen after administration of 8,000 shocks. These preliminary data indicate that lithotripsy can, in some circumstances, produce renal damage in the canine model.

Animals↗