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Biology subjects

Mohsenipour, M.

Publications and source records attributed to Mohsenipour, M..

3 recordsLinked to original sources

Bioengineered visible polymeric mesh to enhance urogynaecological health

Pelvic floor disorders, including pelvic organ prolapse and stress urinary incontinence, are prevalent health concerns, affecting approximately 50% of females over their lifetime, with about 75% of women over 65 years of age being impacted. Traditional surgical interventions, such as transvaginal mesh implants, have led to numerous complications, resulting in their prohibition in several countries. This study introduces an innovative composite mesh designed to mitigate these issues by combining polymethylmethacrylate and thermoplastic polyurethane, further enhanced with iodine-doped carbon nanoparticles to enable visibility via medical imaging. The mesh is coated with 2-methacryloyloxyethyl phosphorylcholine polymer to prevent protein adsorption and promote tissue regeneration. In vitro studies showed high cell viability and low protein adsorption, indicating excellent biocompatibility. Implantation of mesh (with or without iodine) in mice revealed no adverse effects on overall animal health. Mouse spleen weight (an indicator of inflammation) was similar between groups; however, levels of some cytokines (i.e., IL-10, IL-17A and GM-CSF) were elevated following implantation of iodinated mesh in mice suggesting that further refinement of the composite mesh is required. Analysis of the fecal microbiome, which is correlated with physiological states, showed that sham and iodinated mesh implant groups maintained consistent microbial profiles with stable diversity (richness and evenness) measures over time. In contrast, the non-iodinated mesh group exhibited decreased species richness post mesh implantation, likely due to a distinct starting microbiome composition prior to implantation. This research is envisaged to contribute to a safer and more effective solution for treating pelvic floor disorders, providing non-invasive post-implantation monitoring and enhanced mechanical compatibility of surgical mesh with native tissue. Our findings demonstrate that this composite mesh possesses mechanical properties that closely mimic human tissue, ensuring biocompatibility, strength, and flexibility without stimulating significant inflammatory or foreign body responses.

bioengineering↗

Improved gene targeting in vivo using EoHR, a small molecule inhibitor of 53BP1

Precise genome editing by programmable nucleases such as Cas9 has revolutionised medical research by enabling the creation of gene-edited or knock-in mouse models of disease. However, a major limitation of the approach is the inefficient process of homology driven recombination (HDR) from an exogenous DNA repair template. This is because error-prone, 53BP1-dependent non-homologous end joining (NHEJ) predominates at Cas9-induced double strand breaks (DSBs). Here we report the validation of a cell-permeable and non-toxic inhibitor of 53BP1 called EoHR. In vitro, EoHR prevents 53BP1 binding to dimethylated lysine 20 on histone H4, a marker of DSBs. In cells, EoHR prevents localisation of 53BP1 at nuclease mediated DSBs and promotes HDR at a Cas9-induced break. When tested in vivo during mouse Cas9-mediated gene editing, inclusion of EoHR at the time of microinjection more than doubled the recovery of correctly edited mice and halved the time to project success. Our work shows that inhibition of 53BP by EoHR is a simple and robust way to increase HDR at Cas9 breaks that can also dramatically increase the success rates of animal model generation.

biochemistry↗

Hyperimmune bovine colostrum containing lipopolysaccharide antibodies (Imm124-E) has a non-detrimental effect on gut microbial communities in unchallenged mice.

1Enterotoxigenic Escherichia coli (ETEC) is a leading cause of bacterial diarrhea in travelers, military personnel and children in developing countries. Infection has the potential to cause long-term gastrointestinal dysfunction. Preventative treatments for ETEC-induced diarrhea exist, yet the effects of these treatments on gastrointestinal commensals in healthy individuals is unclear. Whether administration of a prophylactic preventative treatment for ETEC-induced diarrhea causes specific shifts in gut microbial populations in controlled environments is also unknown. Here we studied the effects of a hyperimmune bovine colostrum (IMM-124E) used in the manufacture of Travelan(R) (AUST L 106709) on gastrointestinal bacteria in healthy C57BL/6 mice. Using next generation sequencing, we aimed to test the onset and magnitude of potential changes to the mouse gut microbiome in response to the anti-diarrheagenic hyperimmune bovine colostrum product, rich in immunoglobulins against select ETEC strains (Travelan(R), Immuron Ltd). We engineered changes in mouse fecal and cecal bacterial communities by delivering lipopolysaccharide (LPS) antibodies derived from bovine colostrum via dietary supplementation. Holstein Friesian and Jersey cows between 28- and 35-weeks gestation stimulated by subcutaneous delivery of three important pathogenic and antigenic determinants; LPS, flagella, and colonization factor antigen (CFA), produced a hyperimmune colostrum (IMM-124E) with demonstrated beneficial effects on health via modulation of metabolic pathways and immune function. We show that in mice administered colostrum containing LPS antibodies there was an increased abundance of potentially gut-beneficial bacteria, such as Akkermansia and Desulfovibrio, without disrupting the underlying ecology of the gastrointestinal tract. Compared to controls, there was no difference in overall weight gain, body or cecal weights or small intestine length following LPS antibody colostrum supplementation. Overall, dietary supplementation with colostrum containing LPS antibodies produced subtle alterations in gut bacterial composition of mice. Primarily, Travelan(R) LPS antibody treatment decreased the ratio of Firmicutes/Bacteroidetes in gut microbial populations in unchallenged healthy mice. Further studies are required to examine the effect of Travelan(R) LPS antibody treatment to engineer the microbiome in a diseased state and during recovery.

microbiology↗