Negative biomarkers of sperm quality and male fertility

Title from PDF of title page (University of Missouri--Columbia, viewed on June 7, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. Peter SutovskyIncludes bibliographical references.M.S. University of Missouri--Columbia 2011."December 2011"Semen evaluation via traditional light microscopy provides information about sperm motility and basic morphology but has a limited ability to predict reproductive performance in an assisted reproduction setting. In-depth analysis carried out quickly and with repeatable precision on a large number of sperm cells is important to human assisted reproductive therapies (ART) and farm animal biotechnology. As a result, flow cytometric evaluation using biomarkers to detect specific spermatozoon characteristics is growing in popularity in both andrology laboratories and agricultural studs. Here we investigate the application of two biomarkers, the sperm chromatin structure assay (SCSA) and the post-acrosomal ww-domain binding protein (PAWP) to human assisted reproductive therapy and an agricultural bull stud, respectively. Analysis of the results of SCSA, infertility treatment outcomes, and the occurrence of spontaneous abortions (SAB) and multiple births was conducted in 233 couples. A correlation was found between SCSA parameters and SAB, and lower levels of chromatin defects were found in men from couples with triplet pregnancies. In a second trial, semen samples from 162 sires in artificial insemination (AI) service were analyzed using flow cytometry after labeling with an anti-PAWP antibody. Measurements yielded statistically significant correlations between PAWP intensities and several fertility parameters used by the AI industry. Based on these two studies, we conclude that biomarkers such as SCSA and PAWP are useful for the evaluation of spermatozoa and may be predictive of the outcome of assisted reproduction

Missed opportunities to improve food security for pregnant people: a qualitative study of prenatal care settings in Northern New England during the COVID-19 pandemic

Background: Food insecurity during pregnancy has important implications for maternal and newborn health. There is increasing commitment to screening for social needs within health care settings. However, little is known about current screening processes or the capacity for prenatal care clinics to address food insecurity among their patients. We aimed to assess barriers and facilitators prenatal care clinics face in addressing food insecurity among pregnant people and to identify opportunities to improve food security among this population. Methods: We conducted a qualitative study among prenatal care clinics in New Hampshire and Vermont. Staff and clinicians engaged in food security screening and intervention processes at clinics affiliated with the Northern New England Perinatal Quality Improvement Network (NNEPQIN) were recruited to participate in key informant interviews. Thematic analysis was used to identify prominent themes in the interview data. Results: Nine staff members or clinicians were enrolled and participated in key informant interviews. Key barriers to food security screening and interventions included lack of protocols and dedicated staff at the clinic as well as community factors such as availability of food distribution services and transportation. Facilitators of screening and intervention included a supportive culture at the clinic, trusting relationships between patients and clinicians, and availability of clinic-based and community resources. Conclusion: Prenatal care settings present an important opportunity to identify and address food insecurity among pregnant people, yet most practices lack specific protocols for screening. Our findings indicate that more systematic processes for screening and referrals, dedicated staff, and onsite food programs that address transportation and other access barriers could improve the capacity of prenatal care clinics to improve food security during pregnancy

What Are You Afraid Of?

Writings and art about self-care, the judicial system, Adrienne Rich, the portrayal of women in advertising, Andrea Dowrkin, sex roles and pornography, rape culture, Rita Gross, human trafficking, welfare, contraception, Margaret Sanger, The Vagina Monologues, Guerilla Girls, feminism and religion, Sandra Harding, tenure at Chapman based on gender, and Delores Huerta.https://digitalcommons.chapman.edu/feminist_zines/1024/thumbnail.jp

The biological carbon pump in CMIP6 models: 21st century trends and uncertainties

The biological carbon pump (BCP) stores ∼1,700 Pg C from the atmosphere in the ocean interior, but the magnitude and direction of future changes in carbon sequestration by the BCP are uncertain. We quantify global trends in export production, sinking organic carbon fluxes, and sequestered carbon in the latest Coupled Model Intercomparison Project Phase 6 (CMIP6) future projections, finding a consistent 19 to 48 Pg C increase in carbon sequestration over the 21st century for the SSP3-7.0 scenario, equivalent to 5 to 17% of the total increase of carbon in the ocean by 2100. This is in contrast to a global decrease in export production of –0.15 to –1.44 Pg C y–1. However, there is significant uncertainty in the modeled future fluxes of organic carbon to the deep ocean associated with a range of different processes resolved across models. We demonstrate that organic carbon fluxes at 1,000 m are a good predictor of long-term carbon sequestration and suggest this is an important metric of the BCP that should be prioritized in future model studies

Identification of the Inorganic Pyrophosphate Metabolizing, ATP Substituting Pathway in Mammalian Spermatozoa

Inorganic pyrophosphate (PPi) is generated by ATP hydrolysis in the cells and also present in extracellular matrix, cartilage and bodily fluids. Fueling an alternative pathway for energy production in cells, PPi is hydrolyzed by inorganic pyrophosphatase (PPA1) in a highly exergonic reaction that can under certain conditions substitute for ATP-derived energy. Recombinant PPA1 is used for energy-regeneration in the cell-free systems used to study the zymology of ATP-dependent ubiquitin-proteasome system, including the role of sperm-borne proteasomes in mammalian fertilization. Inspired by an observation of reduced in vitro fertilization (IVF) rates in the presence of external, recombinant PPA1, this study reveals, for the first time, the presence of PPi, PPA1 and PPi transporter, progressive ankylosis protein ANKH in mammalian spermatozoa. Addition of PPi during porcine IVF increased fertilization rates significantly and in a dose-dependent manner. Fluorometric assay detected high levels of PPi in porcine seminal plasma, oviductal fluid and spermatozoa. Immunofluorescence detected PPA1 in the postacrosomal sheath (PAS) and connecting piece of boar spermatozoa; ANKH was present in the sperm head PAS and equatorial segment. Both ANKH and PPA1 were also detected in human and mouse spermatozoa, and in porcine spermatids. Higher proteasomal-proteolytic activity, indispensable for fertilization, was measured in spermatozoa preserved with PPi. The identification of an alternative, PPi dependent pathway for ATP production in spermatozoa elevates our understanding of sperm physiology and sets the stage for the improvement of semen extenders, storage media and IVF media for animal biotechnology and human assisted reproductive therapies

Immunofluorescence of ANKH (red) in boar spermatozoa (A) and spermatids (B).

<p>(A) Prominent labeling is present in the postacrosomal sheath, and in the equatorial segment (arrowheads in panel b) of ejaculated spermatozoa. (B) During spermiogenesis, ANKH colocalizes with tubulin (TUBB, green) in the microtubules of the spermatid caudal manchette (a–c) at all steps of spermatid elongation during which the manchette is present (late round/early elongating spermatid-a; late elongating spermatid-b & c; top and side view-d, respectively). This pattern is typical of the deposition of proteins into postacrosomal sheath that serve a structural or metabolic/signaling purpose in fully differentiated spermatozoa. Microtubules were labeled with monoclonal antibody against tubulin beta (TUBB). DNA was counterstained with DAPI (blue). Epifluorescence micrographs were overlaid with parfocal transmitted light photos acquired with DIC optics.</p

Effect of PPi on total and polyspermic fertilization during porcine IVF.

<p>Diagram indicates % monospermic (□) and % polyspermic (▪) fertilization. Values are expressed as the mean percentages of total fertilization ± SEM. Different superscripts a, b & c in each histogram denote a significant difference at p<0.05, meaning that column a is significantly different from columns b and c, column b is significantly different from columns a and c, column ab is not significantly different from either a or b, and column bc is not significantly different from columns b and c. Numbers of inseminated ova are indicated in parentheses. (A) Porcine oocytes matured <i>in vitro</i> were inseminated with a standard concentration of 1×10⁶ spermatozoa/ml, in the presence of ascending concentrations of PPi. Experiments were repeated five times. (B) The polyspermy rates, reflective of sperm fertilizing ability <i>in vitro</i> (same as panel A) dramatically increased in the presence of PPi. (C) Fertilization rates of porcine oocytes inseminated with different concentrations of spermatozoa in the presence/absence of 10 µM PPi. Experiments were repeated three times. (D) Porcine oocytes were inseminated (sperm conc. 5×10⁵ spermatozoa/ml) with (+) or without (−) 10 µM PPi in TBM, using spermatozoa stored with (+) or without (−) PPi in BTS. Experiments were repeated three times. (E) Effect of extrinsic PPA1 enzyme on porcine IVF. Oocytes were inseminated with different concentrations of purified PPA1 protein. Experiments were repeated twice. (F) Porcine oocytes were inseminated in the presence of rabbit polyclonal anti-PPA1 antibody or non-immune rabbit serum (a control of PPA1 antibody). Experiments were repeated twice.</p