A novel methodology for characterization of animal sperm shape involving the use of a spectral approach to multiscale curvature estimation is proposed. By using the derivative property of the Fourier transform, allied to Gaussian smoothing, accurate estimates of the curvature along the sperm contour can be obtained in such a way that the curvature peaks corresponding to the sperm head vertices can be effectively identified. The measurements derived from such a processing, namely the width of the basal region of the head, the centralization of tail implantation, and the multiscale bending energy, provide valuable resources for fertility and phylogenetic studies.
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http://dx.doi.org/10.1016/j.compbiomed.2004.03.007 | DOI Listing |
J Homosex
March 2025
Swedish Institute for Social Research, Stockholm University, Stockholm, Sweden.
In the Netherlands, lesbian couples have a relatively high level of agency in shaping conception, as they can choose between different donor constructions (sperm bank donor versus contact donor), high- and low-tech medical interventions, and clinical and non-clinical inseminations. This results in pluriform conceptive practices, which this paper examines through the lens of , i.e.
View Article and Find Full Text PDFBiochem Biophys Res Commun
March 2025
Department of Physics, Prithvinarayan Campus, Tribhuvan University, Pokhara, Nepal. Electronic address:
DNA compaction by polyaminic cations and proteins involves reversible condensation mechanisms. Polyamines, metal cations, and histone proteins are utilized to compact lengthy DNA chains. Chromatin organization begins with nucleosomal arrays, further compacted by linker histones.
View Article and Find Full Text PDFHum Reprod Open
February 2025
Department of Medical Statistics, School of Public Health, Sun Yat-Sen University, Guangzhou, Guangdong, China.
Study Question: Is paternal age associated with neonatal outcomes?
Summary Answer: Paternal age is independently associated with preterm birth (PTB) and caesarean section.
What Is Known Already: Advanced maternal age has long been recognized as a major risk factor for adverse neonatal outcomes. However, the association between paternal age and neonatal outcomes are not well established, yet it is biologically plausible that an increasing number of genetic and epigenetic sperm abnormalities in older males may contribute to adverse neonatal outcomes.
Hum Reprod Update
March 2025
Institute of Reproduction and Stem Cell Engineering, NHC Key Laboratory of Human Stem Cell and Reproductive Engineering, School of Xiangya Basic Medical Sciences, Central South University, Changsha, Hunan, China.
Background: Sperm head shaping, controlled by the acrosome-acroplaxome-manchette complex, represents a significant morphological change during spermiogenesis and involves numerous proteins expressed in a spatially and temporally specific manner. Defects in sperm head shaping frequently lead to teratozoospermia concomitant with oligozoospermia and asthenozoospermia, but the pathogenic mechanism underlying sperm head shaping, and its role in male infertility, remain poorly understood.
Objective And Rationale: This review aims to summarize the mechanism underlying sperm head shaping, reveal the relationship between gene defects associated with sperm head shaping and male infertility in humans and mice, and explore potential clinical improvements in ICSI treatment.
Nat Struct Mol Biol
March 2025
Department of Microbiology and Molecular Genetics, University of California, Davis, CA, USA.
Spermatogenesis is a unidirectional differentiation process that generates haploid sperm, but how the gene expression program that directs this process is established is largely unknown. Here we determine the high-resolution three-dimensional (3D) chromatin architecture of mouse male germ cells during spermatogenesis and show that CTCF-mediated 3D chromatin dictates the gene expression program required for spermatogenesis. In undifferentiated spermatogonia, CTCF-mediated chromatin interactions between meiosis-specific super-enhancers (SEs) and their target genes precede activation of these SEs on autosomes.
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