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Ashraf Ali

Publications and source records attributed to Ashraf Ali.

3 recordsLinked to original sources

The importance of integrating genetic testing into reproductive medicine: a retrospective observational study investigating the monogenic causes of human infertility in couples considering ICSI.

The genetic landscape of human infertility is complex with diverse etiologies. Identifying the underlying etiology is crucial for guiding reproductive decisions and improving management for infertile couples. Here, we aim to report on the molecular spectrum of monogenic genetic causes of reproductive failure. Over a 3-year period, we recruited all infertile couples considering assisted reproductive technologies (ART) for whom the underlying genetic cause had been identified, in either partner, using exome sequencing (ES). Clinical data of all participants along with their hormonal profiles, sonographic findings and spermograms were recorded. The study included 50 couples with primary infertility. Clinically, male factor infertility was documented in 26 patients, female factor infertility in 10, while reproductive failure was unexplained in the remaining 14 couples. All participating couples had potentially disease-causing variants in infertility genes. ES identified variants related to male infertility in 26 men, while variants in female infertility-related genes were detected in the remaining couples (n = 24). According to ACMG classification criteria, 78% (39/50) of couples harbored pathogenic/likely pathogenic (P/LP) variants, whereas 22% (11/50) carried variants of uncertain significance (VUS). In view of the identified genetic etiologies, the cohort was stratified into two groups based on the predicted reproductive outcome: (1) couples with significantly impaired reproductive potential, and (2) couples who can have biological children using appropriate medical interventions. However, classifications involving VUS were interpreted cautiously and considered exploratory. This study provides further evidence for the molecular heterogeneity of human infertility and highlights the usefulness of genetic testing for infertile couples pursuing ARTs.

Humans↗

Silicon oxide nanoparticles reveal the origin of silicate grains in circumstellar environments.

A synergistic effort combining experiments in beams and first principles theoretical investigations is used to propose mechanisms that could lead to the formation of silicates and nanoparticles with silicon-rich cores through agglomeration of SiO, an abundant oxygen-bearing species in space. The silicon oxygen species involved in the transformation have optical excitations that could contribute to extended red emissions and blue luminescence. Apart from resolving an outstanding astronomical problem, we demonstrate novel silicon architectures.

Computer Simulation↗

Modelling the behaviour of ligaments: a technical note.

Experimental observations suggest that during a ligament tensile strain test, water and glycosaminoglycans are exuded. Many attempts have been tried to model this behaviour using continuum mechanics. We have investigated this unique behaviour and have established three mechanisms which may contribute to the experimental observations: the slackness of the fibres before stretching can lead to a decrease in volume upon straightening; a Poisson's ratio higher than 0.5 from the axial to the lateral direction (as recorded in the literature [Hewitt, J., Guilak, F., Glisson, R. and Parker Vail, T. (2001) "Regional material properties of the human hip joint capsule ligaments", Journal of Orthopaedic Research 19(3), 359-364]) due to the very high level of anisotropy of the tissue; and an osmotic pressure, with a certain level of anisotropy, that causes the swelling of the tissue before loading [Thornton, G.M., Shrive, N.G. and Frank, C.B. (2001) "Altering ligament water content affects ligament pre-stress and creep behaviour", Journal of Orthopaedic Research 19(5), 845-851]. There may be other mechanisms that also contribute in the observed fluid exudation on tensile loading.

Anisotropy↗