The origins of DNA damage in mammalian spermatazoa

The development of in vitro fertilisation (IVF) and intra-cytoplasmic spermatozoa injection (ICSI) techniques has revolutionised treatment for couples with so- called male-factor infertility. However concern over the integrity of the DNA in spermatozoa used for ICSI has been expressed. Poor semen quality and morphologically abnormal spermatozoa are associated with poor embryonic development following IVF. Furthermore, studies have demonstrated that the transmission of defective DNA (e.g. adducts, gene deletions) from the spermatozoa to the developing embryo can occur and that this may lead to developmental failure of the embryo or future health risks for the child. The aims of this project were; a) to develop a Comet assay for the study of DNA integrity of murine spermatozoa, b) to use this assay to assess DNA integrity in spermatozoa from mice with known sub /infertility and to examine the susceptibility of these spermatozoa to heat -induced DNA damage, c) to identify the stages of spermatogenesis in wild type mice which are susceptible to heat-induced DNA damage, and d) to determine whether this damage is present in the mature spermatozoa developed from heat-treated germ cells.The single-cell gel-electrophoresis (Comet) assay was originally developed to study DNA damage in somatic cells and has been modified to study both endogenous and induced DNA damage in human ejaculated spermatozoa. DNA packaging and condensation in mouse spermatozoa is not identical to that in the human. The human spermatozoa Comet assay was therefore not suitable for use on murine spermatozoa. A series of modifications were made to the human spermatozoa Comet assay and a usable assay based on a commercially-available Comet Assay Kit (Trevigen) was developed for the study of murine spermatozoa.The motility, morphology and DNA integrity of motile spermatozoa recovered from the epidiymes of four transgenic lines of mice, all of which suffered from male infertility/subfertility, were examined. Deleted in azoospermia-like autosomal ( Dazla)-deficient mice (-/-) are infertile, and males fail to produce any mature spermatozoa; heterozygous (+ /-) males are fertile but exhibit reduced numbers of spermatozoa with high incidence of morphological abnormality. Reduced numbers of motile spermatozoa and increased incidence of morphological abnormalities in motile spermatozoa from +l- Dazla mice was observed. Compared to wild type ( + / +) mice, the level of DNA damage in the spermatozoa of +/- mice was significantly higher. Levels of DNA damage in both +1+ and +/- were increased following in vitro heat treatment. Similar findings were also observed in mice with excision repair cross - complementation gene 1 (ercc -1) genotypes ( +/- and -/ -). ERCC1 is involved in the nucleotide excision repair (NER) pathway and mitotic recombination process, and is highly expressed in the testis. Deletion of the Prion protein (PrP) or the PrP- related gene Doppel (PrnD) also resulted in lower numbers of motile spermatozoa with higher levels of DNA damage. However, following in vitro heating, levels of DNA damage in the motile spermatozoa from these mice did not increase.To investigate the effects of heat stress on DNA integrity, wild type mice (Dazia +/+) underwent scrotal heating (42°C, 30 min) and were then sacrificed at various time points; 1, 2, 4, 6 or 24 hours (h) or 7, 14, 21, 24, 28, and 32 days (d) after heat stress. Testes and epididymides were removed and fixed for histological analysis, and motile epididymal spermatozoa were retrieved. Altered expression of Cirp (a heat-response protein), heat shock protein 105 (HSP105) and Bax (a pro-apoptotic protein), together with increased numbers of TUNEL-positive cells were detected in testes. Expression of Cirp, Bax and the macrophage marker CD68 were also altered in the epididymis. Levels of DNA damage in motile spermatozoa increased significantly within lh of heating, reaching a peak at 4h and then recovering to control levels at 7 and 14d. At 21d after heating, DNA damage increased again reaching a second peak at 28d and failing to recover by 32d.These results indicate that motile spermatozoa in the epididymis are susceptible to heat-induced DNA damage. Furthermore, while DNA integrity of spermatozoa derived from spermatids subjected to heat stress is normal, loss of DNA integrity in pre-meiotic germ cells caused by heat stress is not repaired as these cells mature, resulting in motile spermatozoa with impaired DNA integrity. These findings suggest that it may be necessary for additional criteria to be taken into consideration when selecting spermatozoa for ICSI/IVF treatment

Pilot Study: HPV Infection Knowledge & HPV Vaccine Acceptance among Women Residing in Ciudad Juárez, México

The human papillomavirus (HPV) is one of the most common sexually transmitted infections (STI) in the world and it is associated with cervical cancer. The development of a prophylactic HPV vaccine has proven effective in clinical trials and it is now available to the public. The HPV vaccine represents a viable prevention strategy against cervical cancer. However, parental preferences, perceptions, and willingness to use the HPV vaccine are crucial, and if not assessed accurately, may threaten the successful implementation of a broad HPV vaccination program. This pilot study explored the views of 60 adult, Mexican women, all of who were mothers of female children between the ages of ten to 14 years old on the following four areas of interest: HPV knowledge; HPV vaccine knowledge and attitudes; barriers to HPV vaccine use; and potential uses and side effects of the HPV vaccine. Only 7% of respondents knew that HPV was a virus or STI. Eighty-six percent had not heard of the HPV vaccine, but 62% felt that the HPV vaccine would prevent HPV infection. However, 38% said the church would not approve of the HPV vaccine use for 10-14-year-old girls. Twenty-seven percent thought that promiscuous behavior would increase following HPV vaccination. Overall, respondents had very little knowledge of the HPV vaccine, were willing to be vaccinated themselves (83%), but were lesser willing to vaccinate their daughters (63%). Ultimately, understanding the beliefs about and identifying the barriers of HPV vaccine use will influence the effectiveness of the vaccine and its potential impact in reducing cervical cancer incidence rates worldwide

Tropical understory herbaceous community responds more strongly to hurricane disturbance than to experimental warming

Ecology and Evolution published by John Wiley & Sons Ltd. The effects of climate change on tropical forests may have global consequences due to the forests’ high biodiversity and major role in the global carbon cycle. In this study, we document the effects of experimental warming on the abundance and composition of a tropical forest floor herbaceous plant community in the Luquillo Experimental Forest, Puerto Rico. This study was conducted within Tropical Responses to Altered Climate Experiment (TRACE) plots, which use infrared heaters under free-air, open-field conditions, to warm understory vegetation and soils + 4°C above nearby control plots. Hurricanes Irma and María damaged the heating infrastructure in the second year of warming, therefore, the study included one pretreatment year, one year of warming, and one year of hurricane response with no warming. We measured percent leaf cover of individual herbaceous species, fern population dynamics, and species richness and diversity within three warmed and three control plots. Results showed that one year of experimental warming did not significantly affect the cover of individual herbaceous species, fern population dynamics, species richness, or species diversity. In contrast, herbaceous cover increased from 20% to 70%, bare ground decreased from 70% to 6%, and species composition shifted pre to posthurricane. The negligible effects of warming may have been due to the short duration of the warming treatment or an understory that is somewhat resistant to higher temperatures. Our results suggest that climate extremes that are predicted to increase with climate change, such as hurricanes and droughts, may cause more abrupt changes in tropical forest understories than longer-term sustained warming

Risk of Long Covid in people infected with SARS-CoV-2 after two doses of a COVID-19 vaccine: community-based, matched cohort study

We investigated Long Covid incidence by vaccination status in a random sample of UK adults from April 2020 to November 2021. Persistent symptoms were reported by 9.5% of 3,090 breakthrough SARS-CoV-2 infections and 14.6% of unvaccinated controls (adjusted odds ratio 0.59, 95% CI: 0.50-0.69), emphasising the need for public health initiatives to increase population-level vaccine uptake

A New High Contrast Imaging Program at Palomar Observatory

We describe a new instrument that forms the core of a long-term high contrast imaging program at the 200-inch Hale Telescope at Palomar Observatory. The primary scientific thrust is to obtain images and low-resolution spectroscopy of brown dwarfs and young Jovian mass exoplanets in the vicinity of stars within 50 parsecs of the Sun. The instrument is a microlens-based integral field spectrograph integrated with a diffraction limited, apodized-pupil Lyot coronagraph, mounted behind the Palomar adaptive optics system. The spectrograph obtains imaging in 23 channels across the J and H bands (1.06 - 1.78 microns). In addition to obtaining spectra, this wavelength resolution allows suppression of the chromatically dependent speckle noise, which we describe. We have recently installed a novel internal wave front calibration system that will provide continuous updates to the AO system every 0.5 - 1.0 minutes by sensing the wave front within the coronagraph. The Palomar AO system is undergoing an upgrade to a much higher-order AO system ("PALM-3000"): a 3388-actuator tweeter deformable mirror working together with the existing 241-actuator mirror. This system will allow correction with subapertures as small as 8cm at the telescope pupil using natural guide stars. The coronagraph alone has achieved an initial dynamic range in the H-band of 2 X 10^-4 at 1 arcsecond, without speckle noise suppression. We demonstrate that spectral speckle suppression is providing a factor of 10-20 improvement over this bringing our current contrast at an arcsecond to ~2 X 10^-5. This system is the first of a new generation of apodized pupil coronagraphs combined with high-order adaptive optics and integral field spectrographs (e.g. GPI, SPHERE, HiCIAO), and we anticipate this instrument will make a lasting contribution to high contrast imaging in the Northern Hemisphere for years.Comment: Accepted to PASP: 12 pages, 12 figure

What WorX: Measuring the impact of faith-based service and social justice programs on Catholic youth

The Center for FaithJustice (CFJ) offers innovative programs that engage youth in faith, service, and social justice. With the Indiana University Lilly Family School of Philanthropy at IUPUI, they developed a survey to evaluate their programs and measure their longitudinal impact on alumni in those three focus areas. This report will offer related insights on youth engagement and suggest how CFJ’s programs relate to larger trends of youth disaffiliation within the Catholic Church. This study examines survey results from alumni and parents of alumni of CFJ’s youth programs, which are collectively called the “WorX” programs. These include curricula for middle school students (ServiceworX), high school students (JusticeworX, New Jersey Service Project/NJSP, MercyworX, and CommunityworX), young adults (LeaderworX), and adults (FaithJustice Fellows and adult volunteers). The results of this study focused on CFJ’s three core areas of interest: faith, service, and social justice

Spectral Typing of Late Type Stellar Companions to Young Stars from Low Dispersion Near-Infrared Integral Field Unit Data

We used the Project 1640 near-infrared coronagraph and integral field spectrograph to observe 19 young solar type stars. Five of these stars are known binary stars and we detected the late-type secondaries and were able to measure their JH spectra with a resolution of R\sim30. The reduced, extracted, and calibrated spectra were compared to template spectra from the IRTF spectral library. With this comparison we test the accuracy and consistency of spectral type determination with the low-resolution near-infrared spectra from P1640. Additionally, we determine effective temperature and surface gravity of the companions by fitting synthetic spectra calculated with the PHOENIX model atmosphere code. We also present several new epochs of astrometry of each of the systems. Together these data increase our knowledge and understanding of the stellar make up of these systems. In addition to the astronomical results, the analysis presented helps validate the Project 1640 data reduction and spectral extraction processes and the utility of low-resolution, near-infrared spectra for characterizing late-type companions in multiple systems.Comment: Accepted to Astronomical Journal, 25 pages, 8 figure