Vision impairments affect over 2.2 billion people worldwide. The most physiologically accurate human retina models are Retinal Organoids (ROs) — stem cell-derived structures containing the major cell types found in the human retina. However, the current protocol for deriving ROs from stem cells is highly labor-intensive and involves a time-consuming neural induction period. In this study, we investigated an alternative differentiation protocol that could decrease the neural induction period from two weeks to four days and elucidate the essential parameters, such as seeding density, required for neural induction of ROs. Expediting the neural induction of RO progenitors can be applied to improve efficiency in the differentiation of ROs.

We characterized RO progenitors using gene expression data from qPCR and by visual inspection with bright-field microscopy. Although seeding density has historically been shown to affect gene expression in the culture of ocular cells, seeding density did not significantly (p > .05) impact the gene expression or morphology of cells at the tested time points of differentiation. Cells on day 4 (D4) of differentiation demonstrated morphology and neural gene expression (Pax6 and Lhx2) characteristic of neural cells. Additionally, transferring cells from adherent culture to suspension culture on day 2 (D2) instead of D4 of this differentiation yielded intact neural spheres with a phase-bright outer ring and defined borders after 14 days of culture. Therefore, these results indicate that our alternative differentiation protocol successfully expedited the neural induction of RO progenitors. These results will contribute to the establishment of a more efficient neural induction when generating ROs, which may expedite the production of RO-based retinal therapies.

Neurodegenerative diseases have debilitating consequences for the health and longevity of the nervous system. Parkinson’s disease (PD) is one of the most common neurodegenerative disorders with a typical onset between ages 55 and 65 that results from dopamine depletion in the brain. This dopamine loss occurs in the substantia nigra compacta (SNc), which accordingly is the target for many dopamine regeneration techniques. Additionally, several studies have suggested that an accumulation of the large protein, α-synuclein, is responsible for the loss of dopamine in this region. However, the association between α-synuclein and dopamine remains an active area of research. While there is no cure for the disease, pharmacological and surgical treatments have been developed to alleviate PD’s motor and non-motor symptoms. Currently, successful outcomes in experimental models provide hope for the effectiveness of cell therapy in the regeneration of dopamine. However, further investigation is needed to determine its effectiveness in humans. This literature review will highlight current progress in the efforts to restore and prevent the loss of dopamine in the brain as an avenue to treat PD. Among these are dopamine replacement therapy (DRT), Gemfibrozil and carotid body (CB) transplantation.

Acinetobacter venetianus and Alcanivorax borkumensis are bacterial strains capable of degrading hydrocarbons from oils or natural gases. Plastics are often derived from fossil fuels like crude oil and natural gas, with similar chemical structures and formulas to oil. Both products are commonly disposed of improperly and collected in the natural environment with few means for effective removal. Since A. venetianus and A. borkumensis are known to consume hydrocarbons, the ability to consume microplastic Polyethylene (PE), a type of hydrocarbon, will be explored. The bacteria are expected to consume the microplastic fastest when concentrations are highest. The premise of this experiment was to see if bacteria could consume PE and while there was bacterial growth, PE consumption was not being measured directly. Both strains were given high, medium and low concentrations of PE as the sole nutrient source and growth was measured with optical density. In the second trial, A. borkumensis demonstrated a significant difference between samples with PE and control samples, whereas there was no difference in the other trial. In one trial, through the growth phase and after the stationary phase in all concentrations of PE, A. venetianus had a significantly higher OD600 compared to the control. It appears both strains may be capable of consuming microplastics, however continued research is needed to explore whether microplastics are truly consumed or simply broken down further.

Rotenone is a broad-spectrum pesticide and piscicide that inhibits the transport of electrons in NADH-Q-oxidoreductase (complex I), thereby inhibiting cellular respiration. For the past two decades, epidemiologists have suspected that exposure to rotenone increases the risk of developing Parkinsonism. Although restricted for food use in the United States, rotenone is still used in countries exporting produce. Research has determined rotenone’s presence in produce as well as processed food products, such as tea and olive oil, raising the concern that it does not degrade before and during food processing. Furthermore, there are documented issues with the organic certification of imported produce into the United States, including soybeans. Organic and non-organic national brands of soy milk were purchased from a supermarket in the Greater Cleveland Area, and two samples were analyzed in triplicate for rotenone using high-performance liquid chromatography equipped with an ultraviolet light detector (HPLC-UV). A positive determination would indicate that rotenone is not degraded during the process that turns soybeans into milk. The samples were analyzed and compared to samples intentionally spiked with rotenone before they were filtered and dissolved in acetonitrile in preparation for the detection by HPLC- UV. Rotenone was not detected in these samples. However, a reliable method was developed for filtering soy milk and analyzing it for rotenone residues. The method detection limit allows for the determination of rotenone residues in soybeans beyond the maximal residual limit fixed by the European Union.