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William E. Roudebush - One of the best experts on this subject based on the ideXlab platform.

  • Presence of ribonucleic acid in human spermatozoa: differences in content between normal and abnormal spermatozoa.
    American journal of obstetrics and gynecology, 2000
    Co-Authors: Mark D. Wild, William E. Roudebush
    Abstract:

    Abstract Objective: Our purpose was to determine whether there are any differences in total ribonucleic acid content between normal and abnormal human spermatozoa. Study Design: Spermatozoa were obtained from men undergoing routine semen analysis at a university-based Reproductive Genetics laboratory. Specimens were classified as normal or abnormal according to World Health Organization criteria. Total ribonucleic acid was removed by acid-phenol extraction, and ribonucleic acid expression levels were determined by spectrophotometric analysis. Results: Abnormal spermatozoa were found to have significantly more ribonucleic acid (0.14 ± 0.02 mg/10 6 spermatozoa) than normal spermatozoa (0.05 ± 0.01 mg/10 6 spermatozoa; P Conclusion: Ribonucleic acid content is significantly altered in abnormal spermatozoa, and this alteration may be the result of some defect in the posttranscriptional pathway. (Am J Obstet Gynecol 2000;182:1011-2.)

  • Expression of the platelet-activating factor receptor in human spermatozoa: differences in messenger ribonucleic acid content and protein distribution between normal and abnormal spermatozoa.
    Fertility and sterility, 2000
    Co-Authors: William E. Roudebush, Mark D. Wild, Elizabeth H Maguire
    Abstract:

    Abstract Objective: To determine the expression and distribution of the platelet-activating factor (PAF) receptor in normal and abnormal specimens of human spermatozoa. Design: Prospective analysis of membrane-bound PAF receptors by immunofluorescence and PAF receptor messenger RNA by quantitated reverse transcription–polymerase chain reaction in normal and abnormal spermatozoa. Setting: University-based Reproductive Genetics laboratory. Patient(s): Men undergoing routine semen analysis. Intervention(s): Normal and abnormal spermatozoa were exposed to rabbit anti–PAF receptor antibody, fluorescein isothiocyanate–conjugated goat anti-rabbit antibody, and fluorescent microscopy or subjected to RNA isolation by acid-phenol extraction and quantitated (MIMIC Construction Kit [Clontech Laboratories, Inc., Palo Alto, CA]) reverse transcription–polymerase chain reaction. Main Outcome Measure(s): Fluorescent intensities at six locations along spermatozoa (end piece, principal tail, midpiece, neck, proximal head, and acrosomal region) and PAF receptor expression (messenger RNA) levels. Result(s): Immunofluorescence demonstrated a significant difference in PAF receptor distribution between normal and abnormal human spermatozoa, specifically at the neck region. Additionally, abnormal spermatozoa were found to have statistically significantly more PAF receptor messenger RNA than normal spermatozoa. Conclusion(s): Platelet-activating factor receptor expression and distribution are significantly altered in abnormal spermatozoa and this may be the result of some defect in gene transcription.

  • Platelet-activating factor content in human spermatozoa and pregnancy outcome
    Fertility and sterility, 2000
    Co-Authors: William E. Roudebush, Elissa T. Purnell
    Abstract:

    Abstract Objective: To determine whether platelet-activating factor (PAF) content in human spermatozoa from an isolated population is related to fertilization and pregnancy outcome. Design: Prospective analysis of PAF content in human spermatozoa after a Percoll gradient wash and its relation to fertilization and pregnancy outcome. Setting: University-based Reproductive Genetics laboratory. Subject(s): Couples undergoing assisted reproduction. Intervention(s): Lipids extracted from Percoll gradient spermatozoa were quantitated for PAF content by a specific radioimmunoassay. Main Outcome Measure(s): The relation between spermatozoa-derived PAF levels and motility, concentration, morphology, and fertilization and pregnancy rates were determined by using regression analysis and the Student t -test. Result(s): Radioimmunoassay and regression analysis showed a significant and positive relation between PAF content in human spermatozoa and concentration and motility indices and implantation rate. Patients who became pregnant had a significantly higher PAF content in the spermatozoa used (7.285 pmol/10 6 cells) than did patients who did not become pregnant (2.990 pmol/10 6 cells). Conclusion(s): The PAF content in human spermatozoa has a significant and positive relation with motility and concentration indices and implantation rate. Pregnancy rates but not fertilization rates may be predicted by measuring PAF levels in an isolated subpopulation of human spermatozoa.

Mark D. Wild - One of the best experts on this subject based on the ideXlab platform.

  • Presence of ribonucleic acid in human spermatozoa: differences in content between normal and abnormal spermatozoa.
    American journal of obstetrics and gynecology, 2000
    Co-Authors: Mark D. Wild, William E. Roudebush
    Abstract:

    Abstract Objective: Our purpose was to determine whether there are any differences in total ribonucleic acid content between normal and abnormal human spermatozoa. Study Design: Spermatozoa were obtained from men undergoing routine semen analysis at a university-based Reproductive Genetics laboratory. Specimens were classified as normal or abnormal according to World Health Organization criteria. Total ribonucleic acid was removed by acid-phenol extraction, and ribonucleic acid expression levels were determined by spectrophotometric analysis. Results: Abnormal spermatozoa were found to have significantly more ribonucleic acid (0.14 ± 0.02 mg/10 6 spermatozoa) than normal spermatozoa (0.05 ± 0.01 mg/10 6 spermatozoa; P Conclusion: Ribonucleic acid content is significantly altered in abnormal spermatozoa, and this alteration may be the result of some defect in the posttranscriptional pathway. (Am J Obstet Gynecol 2000;182:1011-2.)

  • Expression of the platelet-activating factor receptor in human spermatozoa: differences in messenger ribonucleic acid content and protein distribution between normal and abnormal spermatozoa.
    Fertility and sterility, 2000
    Co-Authors: William E. Roudebush, Mark D. Wild, Elizabeth H Maguire
    Abstract:

    Abstract Objective: To determine the expression and distribution of the platelet-activating factor (PAF) receptor in normal and abnormal specimens of human spermatozoa. Design: Prospective analysis of membrane-bound PAF receptors by immunofluorescence and PAF receptor messenger RNA by quantitated reverse transcription–polymerase chain reaction in normal and abnormal spermatozoa. Setting: University-based Reproductive Genetics laboratory. Patient(s): Men undergoing routine semen analysis. Intervention(s): Normal and abnormal spermatozoa were exposed to rabbit anti–PAF receptor antibody, fluorescein isothiocyanate–conjugated goat anti-rabbit antibody, and fluorescent microscopy or subjected to RNA isolation by acid-phenol extraction and quantitated (MIMIC Construction Kit [Clontech Laboratories, Inc., Palo Alto, CA]) reverse transcription–polymerase chain reaction. Main Outcome Measure(s): Fluorescent intensities at six locations along spermatozoa (end piece, principal tail, midpiece, neck, proximal head, and acrosomal region) and PAF receptor expression (messenger RNA) levels. Result(s): Immunofluorescence demonstrated a significant difference in PAF receptor distribution between normal and abnormal human spermatozoa, specifically at the neck region. Additionally, abnormal spermatozoa were found to have statistically significantly more PAF receptor messenger RNA than normal spermatozoa. Conclusion(s): Platelet-activating factor receptor expression and distribution are significantly altered in abnormal spermatozoa and this may be the result of some defect in gene transcription.

Pao-lin Kuo - One of the best experts on this subject based on the ideXlab platform.

  • Expression of various CDC25B isoforms in human spermatozoa
    Fertility and sterility, 2007
    Co-Authors: Yen Ni Teng, Yung Ming Lin, Chia Ling Chung, Hsien An Pan, Rui Wen Liao, Pao-lin Kuo
    Abstract:

    Objective To explore the role of CDC25B protein in postmeiotic germ cells. Design In vitro experiment. Setting University-based Reproductive Genetics laboratory. Patient(s) Fertile and infertile volunteers. Intervention(s) Reverse transcription-polymerase chain reaction (RT-PCR), real-time RT-PCR, and immunostaining for CDC25B. Main Outcome Measure Expression profiling of CDC25B in human spermatozoa. Result(s) Four splicing variants (CDC25B1, B2, B3, and B4) are expressed in human spermatozoa. Immunofluorescence staining showed strong homogeneous staining in the midpiece of spermatozoa, and weak staining in the principal piece and cytosol of the head. The messenger RNA (mRNA) transcript level of CDC25B was increased in sperm samples of men with asthenospermia. Conclusion(s) The expression of CDC25B in different cellular compartments of human spermatozoa suggests that there are diverse noncell-cycle-related functions of CDC25B in terminally differentiated human germ cells.

  • Presence of DAZL transcript and protein in mature human spermatozoa.
    Fertility and sterility, 2002
    Co-Authors: Yung Ming Lin, Chaio Wei Chen, H. Sunny Sun, Shaw Jeng Tsai, Johnny Shinn Nan Lin, Pao-lin Kuo
    Abstract:

    To identify the DAZL transcript and protein location in human spermatozoa. In vitro experiment. University-based Reproductive Genetics laboratory. A fertile volunteer. Reverse transcription-polymerase chain reaction (RT-PCR), Western blot, and immunostaining for DAZL. Expression of DAZL in human spermatozoa. The DAZL-specific primers yield a 128 bp product in ejaculate. A protein of approximately 33.5 kDa was detected by Western blot analysis. Immunofluorescence staining showed strong homogeneous staining in the midpiece of spermatozoa and weak staining in the principal piece. A speckled-type distribution was found in the head region. The DAZL transcript and protein are present in human spermatozoa. The roles of DAZL protein in sperm motility and in the sperm-oocyte interaction await further investigation.

Steve Dorus - One of the best experts on this subject based on the ideXlab platform.

  • Proteins, transcripts, and genetic architecture of seminal fluid and sperm in the mosquito aedes aegypti
    Molecular & cellular proteomics : MCP, 2018
    Co-Authors: Ethan C. Degner, Yasir H. Ahmed-braimah, Kirill Borziak, Mariana F. Wolfner, Laura C. Harrington, Steve Dorus
    Abstract:

    The yellow fever mosquito, Aedes aegypti,, transmits several viruses causative of serious diseases, including dengue, Zika, and chikungunya. Some proposed efforts to control this vector involve manipulating reproduction to suppress wild populations or to replace them with disease-resistant mosquitoes. The design of such strategies requires an intimate knowledge of Reproductive processes, yet our basic understanding of Reproductive Genetics in this vector remains largely incomplete. To accelerate future investigations, we have comprehensively catalogued sperm and seminal fluid proteins (SFPs) transferred to females in the ejaculate using tandem mass spectrometry. By excluding female-derived proteins using an isotopic labeling approach, we identified 870 sperm proteins and 280 SFPs. Functional composition analysis revealed parallels with known aspects of sperm biology and SFP function in other insects. To corroborate our proteome characterization, we also generated transcriptomes for testes and the male accessory glands-the primary contributors to Ae. aegypti, sperm and seminal fluid, respectively. Differential gene expression of accessory glands from virgin and mated males suggests that transcripts encoding proteins involved in protein translation are upregulated post-mating. Several SFP transcripts were also modulated after mating, but >90% remained unchanged. Finally, a significant enrichment of SFPs was observed on chromosome 1, which harbors the male sex determining locus in this species. Our study provides a comprehensive proteomic and transcriptomic characterization of ejaculate production and composition and thus provides a foundation for future investigations of Ae. aegypti, Reproductive biology, from functional analysis of individual proteins to broader examination of Reproductive processes.

  • Reproductive functions and genetic architecture of the seminal fluid and sperm proteomes of the mosquito Aedes aegypti
    2018
    Co-Authors: Ethan C. Degner, Yasir H. Ahmed-braimah, Kirill Borziak, Mariana F. Wolfner, Laura C. Harrington, Steve Dorus
    Abstract:

    The yellow fever mosquito, Aedes aegypti, transmits several viruses, including dengue, Zika, and chikungunya. Some proposed efforts to control this vector involve manipulating reproduction to suppress wild populations or replacing them with disease-resistant mosquitoes. The design of such strategies requires an intimate knowledge of Reproductive processes, yet our basic understanding of Reproductive Genetics in this vector remains largely incomplete. To accelerate future investigations, we have comprehensively catalogued sperm and seminal fluid proteins (SFPs) transferred to females in the ejaculate using tandem mass spectrometry. By excluding female-derived proteins using an isotopic labelling approach, we identified 870 sperm proteins and 280 seminal fluid proteins. Functional composition analysis revealed parallels with known aspects of sperm biology and SFP function in other insects. To corroborate our proteome characterization, we also generated transcriptomes for testes and the male accessory glands-the primary contributors to Ae. aegypti sperm and seminal fluid, respectively. Differential gene expression of accessory glands from virgin and mated males suggests that protein translation is upregulated post-mating. Several SFP transcripts were also modulated after mating, but >90% remained unchanged. Finally, a significant enrichment of SFPs was observed on chromosome 1, which harbors the male sex determining locus in this species. Our study provides a comprehensive proteomic and transcriptomic characterization of ejaculate production and composition and thus provides a foundation for future investigations of Ae. aegypti Reproductive biology, from functional analysis of individual proteins to broader examination of Reproductive processes.

Mark I. Evans - One of the best experts on this subject based on the ideXlab platform.

  • Aneuploidy and Isolated Mild Ventriculomegaly
    Fetal Diagnosis and Therapy, 2000
    Co-Authors: Melissa Terry, Byron C. Calhoun, Christina C. Apodaca, Brian Pierce, Roderick F. Hume, Laura Martin, William Walker, Mark I. Evans
    Abstract:

    Background: Does the prenatal ascertainment of isolated mild ventriculomegaly increase the a priori risk for aneuploidy when isolated or not associated with advanced maternal age? Does isolated mild ventriculomegaly increase the risk for pediatric developmental delay? Methods: The Wayne State University (WSU) Reproductive Genetics abnormal case data base and the Madigan Army Medical Center (MAMC) experience were reviewed to compare the rates of aneuploidy for cases with fetal ventriculomegaly. Cases were classified by maternal age and associated sonographic markers of aneuploidy. Aneuploidy rates were compared between the isolated ventriculomegaly, ventriculomegaly with advanced maternal age (AMA), and ventriculomegaly associated with multiple anomalies. Rates of aneuploidy were compared to identify association. Results: A total of 118 cases with ventriculomegaly were identified for comparison. Ninety-four cases were identified in the WSU cohort; 46 demonstrated isolated ventriculomegaly alone, and aneuploidy was present in 3/25 (12%) with invasive fetal testing, 0/24 (0%) cases in the MAMC cohort demonstrated aneuploidy. Isolated mild ventriculomegaly cases at MAMC were identified for further tests. Discussion: Although the two study populations vary in age and risk distributions, the attributable risk for isolated mild ventriculomegaly poses a counseling conundrum due to the neurodevelopmental implication of this minor dysmorphism more so than its association with aneuploidy.

  • Determinants of parental decisions after the prenatal diagnosis of down syndrome: bringing in context.
    American journal of medical genetics, 2000
    Co-Authors: David W. Britt, S. T. Risinger, Virginia L. Miller, Mary Mans, Eric L. Krivchenia, Mark I. Evans
    Abstract:

    This article develops the concept of decision context to refer to the combinations of factors that are important in understanding and predicting termination decisions after a prenatal diagnosis of trisomy 21. Four factors are examined: maternal age, gestational age, prior voluntary abortion, and existing children. The cases were studied at the Wayne State University's Reproductive Genetics Clinic. Qualitative comparative analysis, a technique specifically designed for examining the impact of combinations of factors, is used to isolate influential decision contexts. Odds and odds ratios are used to pinpoint outcome differences among different decision contexts. Four alternative decision contexts are especially conducive to choosing to terminate a pregnancy. Two of these involve women of any age and are formed from combinations of gestational age and existing children (existing children and low gestational age, and no children combined with late gestational age). Older women who have not had an abortion and who discover the trisomy 21 anomaly early are likely to choose termination. Younger women who have had an abortion are also likely to choose termination. Our data suggest there are added layers of complexity to patients' decisions that derive from combinations of conditions. An additional, strong implication is that qualitative comparative analysis may be particularly useful in understanding such complexity.

  • Parental decision-making differences between patients in two healthcare systems for choroid plexus cysts.
    The Australian & New Zealand journal of obstetrics & gynaecology, 2000
    Co-Authors: Christina C. Apodaca, Roderick F. Hume, Laura Martin, Mark I. Evans, Wendy J. Evans, Byron C. Calhoun
    Abstract:

    We evaluated the medical-sociological implications of parental perception of risk and decision-making choices for prenatally ascertained choroid plexus cysts (CPC) between two obstetric populations. The Wayne State University (WSU) Reproductive Genetics database and the Madigan Army Medical Center (MAMC) experience were reviewed to compare the rates of aneuploidy and invasive testing for cases with CPC. Aneuploidy rates were compared between those with isolated CPC, CPC with advanced maternal age (AMA), and CPC associated with multiple anomalies. In the WSU cohort 186 cases were identified, of whom 27 (15%) declined invasive fetal testing. In the remaining 159 cases, aneuploidy was present in 2/132 (1.5%) isolated CPC, 3/11 (27%) CPC with AMA, and 15/16 (93%) CPC with multiple anomalies. In the MAMC cohort 107 cases were identified, of whom 99 (92%) declined invasive fetal testing. No aneuploidy cases were found in the 3/12 AMA cases or 5/95 non-AMA cases that underwent amniocentesis. The two cases of aneuploidy with isolated CPC cannot be ignored, and provide an estimated attributable risk of at least 0.8%, a higher risk than 38 years of age. However, the parental sociologic context may be as important for decision-making as the genetic-prognostic risk.

  • Ethical Issues in Reproductive Genetics
    Seminars in perinatology, 1998
    Co-Authors: John C. Fletcher, Mark I. Evans
    Abstract:

    Because of technological developments in Reproductive Genetics, couples now have many options not available a decade ago. Some developments are controversial and deeply divide our society. This article examines some of these issues and establishes guidelines of approach.

  • Technical Aspects of Transcervical Chorionic Villus Sampling
    Fetal diagnosis and therapy, 1994
    Co-Authors: Nelson B. Isada, Mark P. Johnson, Peter G. Pryde, Mordechai Hallak, Mark I. Evans
    Abstract:

    Following the 1990 FDA approval of the Trophocan catheter for use in transcervical chorionic villus sampling (CVS), an increasing number of US physicians have begun offering the procedure. To obtain privileges to perform CVS, some states such as California have enacted legislation requiring the performance of a certain number of CVS procedures in pregnancies in which the patient has already chosen first-trimester abortion. This practice is not universally feasible for legal, logistic, or financial reasons. We describe our approach to training in a busy Reproductive Genetics service. The physician initially trains by performing amniocentesis to optimize skills in ultrasound-directed needle guidance and placement. During this initial period, he or she also assists in performing transabdominal CVS procedures. The initial transcervical CVS cases should be performed in those situations requiring minimal catheter manipulation, or in those individuals undergoing CVS in the setting of spontaneous abortion. Cases of increasing difficulty should only be performed as skill and familiarity increase. For a physician already skilled and experienced in ultrasound-guided invasive procedures, sequential periods of observation at a busy center allows him or her to become familiar with the common pitfalls in performing transcervical CVS, and thus avoid them. Using this approach, we have performed over 5,000 CVS procedures and trained 6 Reproductive Genetics fellows in transcervical CVS.