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A preliminary magnetic resonance spectroscopy study of postmenopausal hormone effects on the brain. ACTA ACUST UNITED AC 2019; 71:392-393. [PMID: 31287251 DOI: 10.23736/s0026-4784.19.04439-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Effects of American Ginseng on Preimplantation Development and Pregnancy in Mice. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2016; 44:981-95. [DOI: 10.1142/s0192415x16500543] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In North America, a high proportion of pregnant women use herbal medications including North American ginseng. This medicinal plant contains high amounts of triterpene saponins (ginsenosides), which are the main bioactive compounds. It is important to assess ginseng’s impact on all reproductive functions to ensure the safety of pregnant women and fetuses. In this study, we defined the concentration-responsive effects of North American alcoholic and aqueous ginseng extracts on preimplantation development in vitro and on pregnancy and post-partum development in the mouse. Two-cell mouse embryos were cultured with 5 different concentrations of whole ginseng root extracts, or ginsenosides Rb1, Rg1 and Re alone, a combinatorial ginsenoside solution and a crude polysaccharide fraction solution. Embryonic development and recovery from each treatment was assessed. To investigate the in vivo effects of ginseng extracts, female mice were gavaged with 50[Formula: see text]mg/kg/day, 500[Formula: see text]mg/kg/day or 2000[Formula: see text]mg/kg/day of either extract (treatment) or water (sham) for 2 weeks prior to mating and throughout gestation. Gestation period, litter size, pup growth and pup sex ratio were evaluated. Oral ginseng consumption did not significantly affect fertility or pregnancy in the mouse. High doses of ginseng (2000[Formula: see text]mg/kg/day) decreased maternal weight gain. Direct treatment of preimplantation embryos in vitro demonstrated that ALC and AQ extract treatment reduced development in a concentration responsive manner, while only ALC extract effects were largely reversible. Treatments with individual or combinatorial ginsenosides, or the polysaccharide fraction solution alone did not impair preimplantation development, in vitro. In conclusion, maternal oral consumption of ginseng has little negative impact on pregnancy in the mouse, however, direct exposure to ginseng extract during mouse preimplantation development in vitro is detrimental.
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High Frequency of Imprinted Methylation Errors in Human Preimplantation Embryos. Sci Rep 2015; 5:17311. [PMID: 26626153 PMCID: PMC4667293 DOI: 10.1038/srep17311] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 10/28/2015] [Indexed: 12/22/2022] Open
Abstract
Assisted reproductive technologies (ARTs) represent the best chance for infertile couples to conceive, although increased risks for morbidities exist, including imprinting disorders. This increased risk could arise from ARTs disrupting genomic imprints during gametogenesis or preimplantation. The few studies examining ART effects on genomic imprinting primarily assessed poor quality human embryos. Here, we examined day 3 and blastocyst stage, good to high quality, donated human embryos for imprinted SNRPN, KCNQ1OT1 and H19 methylation. Seventy-six percent day 3 embryos and 50% blastocysts exhibited perturbed imprinted methylation, demonstrating that extended culture did not pose greater risk for imprinting errors than short culture. Comparison of embryos with normal and abnormal methylation didn’t reveal any confounding factors. Notably, two embryos from male factor infertility patients using donor sperm harboured aberrant methylation, suggesting errors in these embryos cannot be explained by infertility alone. Overall, these results indicate that ART human preimplantation embryos possess a high frequency of imprinted methylation errors.
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Do Multiple Attempts at Embryo Transfer Affect Clinical Pregnancy Rates? JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2014; 36:406-407. [DOI: 10.1016/s1701-2163(15)30586-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Effect of mood states and infertility stress on patients' attitudes toward embryo transfer and multiple pregnancy. Fertil Steril 2013; 100:530-7. [DOI: 10.1016/j.fertnstert.2013.04.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 04/16/2013] [Accepted: 04/18/2013] [Indexed: 10/26/2022]
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Evaluation of preparatory psychosocial counselling for medically assisted reproduction. Hum Reprod 2012; 27:2058-66. [DOI: 10.1093/humrep/des129] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Development and Investigation of a Free and Informed Choice Process for Embryo Donation to Stem Cell Research in Canada. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2006; 28:903-908. [PMID: 17140508 DOI: 10.1016/s1701-2163(16)32279-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVES To develop and investigate a consent process that satisfies the Assisted Human Reproduction (AHR) Act and the Canadian Institutes of Health Research (CIHR) Stem Cell Guidelines, furthers free and informed choice, and fosters embryo donation to human embryonic stem cell (hESC) research. METHODS Consultations were undertaken with an hESC scientist, in vitro fertilization (IVF) team members, and the ethicist-author of the CIHR Guidelines to review the AHR Act, the CIHR Stem Cell Guidelines, the established consent process for embryo donation at University Hospital, London Health Sciences Centre, the characteristics of patients appropriate for contact, and strategies for sensitive recruitment. Invitation-to-participate packages were sent to patients. RESULTS Patients deemed appropriate for contact had indicated their intent to donate embryos to research, had embryos that had been cryopreserved for more than five years, had not received donor gametes, and had publicly listed addresses, with no suggestion of separation of the parties. Strategies developed to promote anonymity, confidentiality, and informed choice included a "firewall" between clinical and research teams and documents reiterating that, if embryos were donated, the woman would have to undergo additional IVF treatment to have a child. Of 40 couples contacted, only 22 agreed to donate embryos to the hESC study. One couple no longer wished to donate embryos to research, one package was returned as undeliverable, and no response was received from 16 couples. CONCLUSIONS The consent requirements of the AHR Act and the CIHR Stem Cell Guidelines should be met. Consider delaying the request for final consent until a significant time after IVF treatment to ensure that patients no longer want their embryos for reproductive purposes and are free from perceptions of coercion. A consent process promoting free and informed choice, sensitive recruitment, and donation of embryos for hESC research should be developed by the Canadian professional bodies.
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Sperm Donation: Implications of Canada’s Assisted Human Reproduction Act 2004 for Recipients, Donors, Health Professionals, and Institutions. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2006; 28:608-615. [PMID: 16916485 DOI: 10.1016/s1701-2163(16)32199-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND On April 22, 2004, the Assisted Human Reproduction Act came into force, prohibiting the purchase of sperm or eggs from donors in Canada. In response to the concerns of medical professionals and some consumers that prohibiting payment would lead to a decline in the number of gamete donors, Health Canada commissioned research on altruistic donor recruitment and recruitment strategies. METHODS Twenty-two studies of sperm donors were located and their findings reviewed. The studies spanned 23 years (1980-2003), were undertaken in a range of countries, and were chosen on the merit of their relevance to the development of recruitment strategies within a policy of altruistic sperm donation. Observations were derived from assessing and comparing the purposes, findings, and implications of the 22 studies. RESULTS Payment for providing sperm was made in all but three studies, although participants in 15 studies indicated clearly that their motivations were primarily altruistic. Observations indicate that men who are more willing to be identified to offspring in the future share demographic characteristics, such as age and parental status, with those who are prepared to donate altruistically. These characteristics appear to be a factor in motivation to donate altruistically. CONCLUSION The studies show that there are men who are prepared to donate sperm without financial payment. The findings suggest that a change is required in the culture of sperm donation, specifically the adoption of a new approach to donor recruitment.
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Comparing a Microdose Flare to a GnRH Antagonist Protocol for Poor Responder Patients Undergoing In-Vitro Fertilization. Fertil Steril 2005. [DOI: 10.1016/j.fertnstert.2005.07.1130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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No Effect of a Mildly Elevated Serum Prolactin (PRL) on the Pregnancy Rate Following Intrauterine Insemination (IUI). Fertil Steril 2005. [DOI: 10.1016/j.fertnstert.2005.07.1132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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The Relationship Between In Vitro Fertilization and Adverse Pregnancy Outcomes: Analysis of a Prospective, Perinatal Database. Fertil Steril 2005. [DOI: 10.1016/j.fertnstert.2005.07.111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Poor responders in assisted reproduction cycles. MINERVA GINECOLOGICA 2005; 57:1-14. [PMID: 15758861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Poor responders represent a challenging group of infertility patients who fail to respond to controlled ovarian hyperstimulation during the course of assisted reproduction treatment. Although poor response has been investigated since the eighties, many aspects of this condition are still controversial and no consensus has been reached on the management of these patients. The existing data cannot be easily compared due to the heterogeneity of the research design and methodology and the number of prospective randomized trials of sufficient sample size is limited. In addition, more research in the identification and understanding of underlying factors is needed together with a better understanding of the patho-physiological basis of ovarian ageing and of the progressive reduction in ovarian reserve. This paper provides an overview on the identification, prediction and management of poor responders undergoing medicated assisted reproduction treatment.
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Abstract
BACKGROUND Cervical pregnancy is a rare condition that can become life-threatening if heavy bleeding occurs. CASE Grace (pseudonym) is a 32-year-old woman who was admitted to hospital at approximately 6 weeks' gestational age after several days of heavy bleeding. Ultrasonographic examination revealed the presence of cervical pregnancy. She received multiple doses of methotrexate with folinic acid rescue, and did not require surgical intervention. Nine months after the resolution of the cervical pregnancy, Grace again became pregnant. She had an uncomplicated gestation and a normal vaginal delivery of a healthy baby at term. CONCLUSION Multiple-dose methotrexate with folinic acid rescue was a safe option for the medical treatment of ectopic cervical pregnancy in this case. Long-term toxicity studies and case reports are required to provide more information regarding safety and for clinicians to individualize treatment regimens.
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Endometriosis related to infertility. MINERVA GINECOLOGICA 2003; 55:407-16. [PMID: 14581883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Endometriosis is a disease affecting the physical health and emotional well being of many women worldwide. General estimates indicate that at least 25% of all women in their 30s and 40s may be suffering from endometriosis and 30-50% of the affected women are also infertile. Medical therapy, surgery and assisted reproduction are the 3 main options available to women affected by this condition. The etiology and pathophysiology of endometriosis-associated infertility are still obscure, despite an enormous effort over many decades. The management of this disease is a source of controversy and so far no consensus has been reached. Most studies show considerable variation in methodology, may not have enough statistical power or report results that are exactly the opposite of what has been previously published. In light of the disagreement that surrounds the study of endometriosis-associated infertility, a new comprehensive multi-centre study should be designed with the international collaboration of all major experts in this field.
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Effects of progestins on progesterone synthesis in a stable porcine granulosa cell line: control of transcriptional activity of the cytochrome p450 side-chain cleavage gene. Biol Reprod 2002; 66:959-65. [PMID: 11906914 DOI: 10.1095/biolreprod66.4.959] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The purpose of the present study was to examine the effects of progestins on progesterone synthesis and expression of the cytochrome P450 cholesterol side-chain cleavage gene (P450(scc)) in a stable porcine granulosa cell line, the JC-410. Cells were incubated for 48 h with the synthetic progestogen-levornorgestrel with or without RU486 (progesterone and glucocorticoid receptor antagonist) or RWJ26819 (progesterone agonist without affinity to glucocorticoid receptors). Both levonorgestrel and RU486 enhanced progesterone accumulation in a dose-dependent manner. RU486 did not antagonize the effects of levonorgestrel, and RWJ26819 had no effect on progesterone production in cultured JC-410 cells. Progesterone and levonorgestrel increased steady state P450(scc) mRNA levels after 3-6 h of treatment. Progesterone and RU486 at 0.1, 1, and 10 microM increased the transcription rate of P450(scc) transiently expressed in JC-410 cells after 18 h of incubation; 30 microM had no effect, and 100 microM suppressed transcription. Levonorgestrel did not affect transcription of the P450(scc) gene, and RWJ26819 reduced its transcription. Progesterone and RU486 significantly decreased the number of cells and total protein content after 72 and 24 h of incubation, respectively. Levonorgestrel had no effect, whereas RWJ26819 increased (24 h) but subsequently reduced (72 h) cell number and protein content. The present results indicate that progestins are capable of directly modulating progesterone biosynthesis in porcine JC-410 granulosa cells. These effects may be exerted in part through the regulation of P450(scc) gene expression. Ostensible differences exist between progesterone and its synthetic analogues in the control of progesterone secretion in the stable porcine granulosa cell line in vitro.
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Premenstrual syndrome. MINERVA GINECOLOGICA 2002; 54:85-95. [PMID: 12032448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Premenstrual syndrome (PMS) affects the quality of life of millions of women. The complexity and variety of clinical presentation together with the cyclic recurrence of affective and somatic symptoms increase the difficulty in understanding and treating the disease. The precise pathophysiology of PMS is still unknown, but it is increasingly believed that, in women with PMS, the sensitive equilibrium between sex-steroids and central neurotransmitters is altered. Several studies have been carried out to understand the origin of the syndrome and to discover new ways of treatment. This review summarizes the most accepted PMS theories and treatments currently available based on the results of the best-designed trials.
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Abstract
Follicle-stimulating hormone (FSH) has a role in folliculogenesis and spontaneous twinning. Using the candidate gene approach, we searched for mutations in the gene encoding the FSH receptor in a woman who had given birth to two sets of dizygotic twins without fertility treatment. We identified two linked mutations (Thr307Ala and Asn680Ser) that were closely associated with this phenotype. We suggest that expression of both mutations increases the sensitivity of the receptor to FSH.
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Recurrent pregnancy loss associated with endometrial hyperechoic areas (endometrial calcifications): a case report and review of the literature. CLIN EXP OBSTET GYN 2000; 27:5-8. [PMID: 10758787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Endometrial calcifications occur sporadically and are associated with infertility. Previous uterine trauma during instrumentation and/or uterine infection are likely involved in their pathogenesis. The association between endometrial calcifications and recurrent pregnancy loss has been very infrequently reported. A 28-year-old woman with a history of two consecutive first trimester pregnancy losses presented with ultrasonographic hyperechoic endometrial areas associated with histologic endometrial calcification foci. A third pregnancy conceived before starting micronized oral progesterone supplementation also spontaneously aborted at eight weeks. During the fourth pregnancy, progesterone supplementation was taken for the initial 12 weeks. The endometrial lesions were no longer detectable and the pregnancy progressed to term without complications. Endometrial calcifications, related to intrauterine bone tissue, have been previously treated with curettage or with endoscopic surgery, and to the best of our knowledge, have not been reported to disappear spontaneously. In this case, regression of the endometrial calcifications and a favorable pregnancy outcome occurred in concert with oral micronized progesterone supplementation. A combination of transvaginal ultrasonography and endometrial biopsy appears to be an effective method for diagnosing and monitoring of this rare condition.
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Future in vitro fertilization pregnancy potential of women with variably elevated day 3 follicle-stimulating hormone levels. Fertil Steril 1996; 65:1238-40. [PMID: 8641506 DOI: 10.1016/s0015-0282(16)58347-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVE To determine the IVF-ET pregnancy potential of women with variably elevated day 3 FSH. DESIGN Cohort evaluation of 1,868 consecutive IVF-ET cycles January 1991 to December 1994. SETTING University hospital infertility unit. PATIENTS Four cohorts of couples were defined based on day 3 FSH determinations with an arbitrary threshold of 20 mIU/mL, only > or = 20 mIU/mL, always < 20 mIU/mL, current < 20 mIU/mL but one previous > or = 20 mIU/mL, and current < 20 mIU/mL but two or more previous > or = 20 mIU/mL (conversion factor to SI unit, 1.00). INTERVENTION In vitro fertilization-embryo transfer. MAIN OUTCOME MEASURE Fetal heart activity on luteal day 40 transvaginal ultrasound. RESULTS No pregnancies occurred in 53 cycles with day 3 FSH only > or = 20 mIU/mL. In 1,750 women whose day 3 FSH levels were always < 20 mIU/mL, the pregnancy rate (PR) per cycle was 16.5%. In 54 cycles in which day 3 FSH was > or = 20 one time only, but < 20 mIU/mL during the treatment cycle, the PR was 5.6%. In 11 cycles where two or more previous FSH determinations were > or = 20 mIU/mL but with a current day 3 FSH < 20 mIU/mL, no pregnancies occurred. CONCLUSION Our data leads us to the conclusion that day 3 FSH determination precede every IVF cycle and that cycles with FSH > or = 20 mIU/mL be canceled. It also suggests that women with two previous elevations of day 3 FSH be discouraged from future IVF cycles. The 5.6% pregnancy per cycle with one previously elevated FSH warrants extreme pessimism in discussion of further cycles.
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Abstract
Several theories suggest that lung carcinomas are not totally separate entities, but are derived from a common precursor, probably of endodermal origin. The histological classification of lung cancers is complex, with much overlap between groups broadly designated as small cell (SCLC), squamous cell, adenocarcinoma and all others simply termed non-small cell. It is shown here that in vitro exposure of classic, non-adherent SCLC lines to 10 microM 5' bromodeoxyuridine (BrdU) results in a rapid cell-line dependent change to a morphology consistent with an adherent, non-small cell phenotype. Accompanying this morphological shift is a decreased expression of the amplified N-myc protooncogene. These induced changes underline the morphological relatedness of lung carcinoma cell lines.
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Human melanoma-associated antigen expression on human neuroblastoma cells: effects of differentiation inducers. Cancer Immunol Immunother 1991; 32:261-72. [PMID: 1847843 PMCID: PMC11038694 DOI: 10.1007/bf01789043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/1990] [Accepted: 08/30/1990] [Indexed: 12/29/2022]
Abstract
We have described two human melanoma-associated antigens (HMAA), recognized by the murine monoclonal antibodies LS62 and LS109. LS62 recognizes the neuroglandular antigen (NGA), which is overexpressed in neoplastic melanocytes as well as in several tissues of neuroectodermal origin. These antibodies were used to screen six neuroblastoma cell lines and one neuroepithelioma cell line. A melanoma cell line, G361, known to express the two antigens, was used as the positive control. Variable expression of the two antigens was detected in neuroblastoma cells. The surface expression of NGA and of the LS109 antigen was modulated in parallel with the morphological differentiation induced by retinoic acid, 5-bromodeoxyuridine, or cyclic AMP analog/activators. The modulation of the expression of the two HMAA was detected in G361 melanoma cells and in one of the neuroblastoma cell lines, SK-N-SH. These results suggest altered expression of both antigens during melanoma and neuroblastoma cell differentiation in culture.
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Effects of retinoic acid and bromodeoxyuridine on human melanoma-associated antigen expression in small cell lung carcinoma cells. Oncology 1991; 48:58-64. [PMID: 1846233 DOI: 10.1159/000226896] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The dispersed neuroendocrine system includes cells with different embryological derivations, sharing a common neuroendocrine (NE) program, as indicated by the expression of NE markers, some of which are shared antigenic determinants. We report here that the small cell lung carcinoma cells NCI-H69 express the two human melanoma-associated antigens (HMAA) NGA/LS62 an LS109. Incubation of NCI-H69 cells with maturational inducers, such as retinoic acid and bromodeoxyuridine (BrdU), upregulated the expression of both HMAA. Exposure to BrdU for 4 weeks induced the appearance of a different phenotype in subpopulations of NCI-H69 cells, which became epithelioid, substrate-adherent, grew in monolayer and continued to express NE-associated antigens in variable amount. The shift in phenotype was not reversible after BrdU withdrawal and was maintained for at least 6 months in continuous culture. The substrate adhesion of NCI-H69 cells was paralleled by a change in NGA glycosylation pattern, thus suggesting a possible functional role for NGA in cell substrate adhesion/recognition.
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Melanocytic differentiation of human neuroblastoma: expression of a human melanosome-associated antigen. J Invest Dermatol 1990; 95:665-70. [PMID: 2123495 DOI: 10.1111/1523-1747.ep12514336] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Five human neuroblastoma cell lines were examined for expression of a human melanosome-associated antigen (HMSA). Only cell line SK-N-SH reacted with a monoclonal antibody, HMSA-2, shown to recognize melanosomal glycoproteins. To further characterize the melanocytic lineages of SK-N-SH, three morphologically distinct clones designated SK-N-SH-N (neuroblast type), SK-N-SH-F (fibroblast type), and SK-N-SH-EP (epithelial type) were established by colony formation cloning. By fluorescence-activated cell sorter analysis and tyrosinase assay, we found that only SK-N-SH-EP and SK-N-SH-F reacted with HMSA-2 and had tyrosinase activity. These results suggest that epithelial-type and fibroblast-type cells appear to possess the melanocytic potential, but not neuroblast-type cells. Furthermore, SK-N-SH-EP was found to spontaneously convert to neuroblast-type or fibroblast-type cells, whereas SK-N-SH-N and SK-N-SH-F clones have remained morphologically stable. Our results suggest that at least one neuroblastoma cell line, SK-N-SH, may be an excellent model for investigating clonal maturation and the melanocytic differentiation of neuroblastoma.
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Inhibition of neuroglandular antigen (NGA) glycosylation by phorbol ester in human melanoma cells. Biochem Biophys Res Commun 1989; 158:837-43. [PMID: 2645870 DOI: 10.1016/0006-291x(89)92798-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
NGA is a human melanoma-associated antigen recognized by a panel of murine monoclonal antibodies developed in this laboratory. NGA consists of a 23.5 kDa core protein which is glycosylated in vivo to give a family of glycoproteins (30-60 kDa). Treatment of human melanoma G361 cells with the phorbol ester PMA resulted in apparent partial inhibition of NGA glycosylation. After PMA treatment, NGA appeared as 3 different bands of 24, 29 and 34 kDa on SDS-PAGE. The 29 kDa band is similar to the one obtained by treatment with the ionophore monensin, which inhibits NGA O-glycosylation. PMA can modulate plasma membrane ion exchange, most likely by activating protein kinase C. In G361 cells PMA may produce the same net effect as monensin, by impairing transport in the Golgi complex and consequently inhibiting protein O-glycosylation through an ionophore-like effect. Treatment of G361 cells with both PMA and protein kinase C inhibitors re-established the usual NGA glycosylation pattern. Thus the observed effect of PMA on NGA glycosylation is reversible and appears to be mediated by protein kinase C activation.
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Inhibitory effect of the intrauterine infusion of phorbol 12-myristate 13-acetate and 1-oleoyl-2-acetylglycerol on the decidual cell reaction in rats. Biol Reprod 1987; 37:96-104. [PMID: 3115327 DOI: 10.1095/biolreprod37.1.96] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
In rats, prostaglandins (PGs) have an essential role in the decidual cell reaction (DCR), but their mechanism of action at the cellular level within the endometrium is at present uncertain. To test the hypothesis that both protein kinase C activation and calcium mobilization mediate the action of PGs within the endometrium during decidualization, the phorbol ester phorbol 12-myristate 13-acetate (PMA) or the synthetic diacylglycerol 1-oleoyl-2-acetyl-glycerol (OAG), activators of protein kinase C in vitro, and the calcium ionophore A23187, which causes calcium mobilization, were infused, alone or combined, into the uterine lumen of rats sensitized for the DCR. The results obtained indicate that both PMA and OAG have an inhibitory effect on the DCR in rats. The calcium ionophore A23187, although having no apparent effect by itself, had a synergistic effect with PMA, but not with OAG, in inhibiting the DCR. The intrauterine infusion of PMA and/or A23187 had no effect on the increase in endometrial vascular permeability (EVP), which precedes the DCR. The inhibitory effect of PMA or PMA plus A23187 on decidualization is probably not mediated by a decrease in uterine PG synthesis, as assessed by the measurement of uterine prostaglandin E concentrations at various times during the intraluminal infusion. These data suggest that activation of protein kinase C can modulate the DCR.
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