Design and Fabrication of Flow-Focusing Devices for Tissue Engineering Applications

While the lifespan of humans has increased, the durability of cartilage has not, leading to increasing rates of arthritis in aging humans. As both natural and surgical methods for repairing osteochondral defects tend to fall short, UVM’s Engineered Biomaterials Research Laboratory (EBRL) is working towards a solution where biomimetic, polymeric, and porous engineered tissue scaffolds are seeded with drugs and human mesenchymal stem cells (hMSCs). The seeded scaffold is then implanted or injected into the patient’s osteochondral defect, where the hMSCs differentiate and grow a new cartilaginous extracellular matrix to heal the defect as the artificial scaffold breaks down. Microspheres in three distinct size ranges are required to create pores and embed drugs and cells in the scaffold. In order to produce these microspheres, we turn to the field of microfluidics, which examines fluid interactions at micro-scale geometries and flow rates. A microfluidic flow-focusing device (MFFD) leverages the low Reynolds numbers and pronounced effects of surface tension in such flows to create highly monodisperse droplets of one fluid in a second. This project investigates the design and fabrication of MFFDs for the production of homogeneous microspheres. A MFFD must be consistently reproducible, readily characterized, and easy to test and use. MFFDs show great potential to successfully play a role in the EBRL’s investigation of engineered tissue scaffolds

Re: Impact of Fresh Versus Cryopreserved Testicular Sperm Upon Intracytoplasmic Sperm Injection Pregnancy Outcomes in Men with Azoospermia Due to Spermatogenetic Dysfunction: A Meta-Analysis

Azoospermia affects up to 15% of men seeking evaluation for infertility. Sperm retrieval from testicular tissue and using for intracytoplasmic injection to the oocytes is the only treatment option for men with nonobstructive azoospermia (NOA). Although the use of fresh sperm for intracytoplasmic sperm injection (ICSI) is widely used in many centers all around the world, it brings the risk of 50% cancellation of the procedure if no sperm extract from testicular tissue. Contrary to that freezing testis sperm offers many advantages, ie TESE operation can be scheduled electively, women do not need to go simultaneous procedures and most importantly couple knows whether they have enough sperm to proceed for IVF. This meta-analysis demonstrates that men with NOA the fertilization and pregnancy rates are similar with fresh and frozen sperm retrieved from the testis. However physician should have to inform their patients who have cryopreserved very low count of testicular sperm that after thawing some or all sperm may lose their vitality

Role of Abnormal Sperm Morphology in Predicting Pregnancy Outcomes

The evaluation of strict morphology for predicting successful pregnancy has been controversial, nevertheless remains an essential component of semen analysis. Patients with teratozoospermia (abnormal strict morphology) have traditionally been counseled to undergo assisted reproduction. However, recent studies suggest that patients with abnormal sperm morphology alone should not be precluded from attempting natural conception before undergoing assisted reproduction. The goal of this review is to provide an update on the evaluation of sperm morphology for prognosis in assisted reproductive techniques such as intrauterine insemination and in vitro fertilization with or without intracytoplasmic sperm injection. Additionally, we propose a logical approach to the evaluation of a patient with teratozoospermia seeking fertility treatment

Diverse monogenic subforms of human spermatogenic failure

The GEMINI consortium sequenced 1,000 cases of idiopathic male infertility and identified a plausible Mendelian cause in 20% of cases. The infertility genes can be grouped by expression pattern, facilitating their interpretation and follow-up