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Growing meat in vitro using tissue engineering and bioproduction techniques (cellular agriculture) has become an increasingly promising solution to the global food security challenge. Our lab has established methods to cultivate bovine muscle tissue on decellularized plants, representing a viable low-cost, sustainable method to grow meat on edible scaffolds. Most work in this area has focused on the use of edible plant materials (i.e., spinach leaves, apple, broccoli) with inherent economic value. Harvest waste such as corn husk or jackfruit represent abundant sources of cellulose for scaffold production and may be a viable alternative. The present study aims to investigate production of cultured meat through tissue engineering and bioproduction on decellularized, edible samples of corn husk and jackfruit rind. Corn husks and jackfruit rinds were exposed to immersion decellularization. DNA quantification and histological analysis demonstrated sufficient decellularization (0.17 ± 0.06 and 0.07 ± 0.00 ug DNA/g tissue for corn husk and jackfruit rinds, respectively). Following decellularization, corn husk scaffold stiffnesses decreased from 56.67±16.71 MPa to 12.95±2.43 MPa in fiber-aligned direction, while jackfruit decreased from 7.54 ±2.42 MPa to 2.47±1.47 MPa. Seeded scaffolds with bovine satellite cells (BSCs) (11.45±2.24 ug/ul lysate/Gram) and avian (QM7s) (12.90±1.99 ug/ul lysate/Gram) demonstrated increased protein yields on jackfruit scaffolds. QM7 cultured on corn husk scaffolds yielded increased protein but PBSCs seeded on corn husks did not yield protein content higher than controls (QM7 on corn husk: 16.28±3.55, PBSCs on corn husks: 9.57±1.56 ug/ul lysate/Gram, control: 6.35±1.43 ug/ul lysate/Gram). Additionally, cell transfer from scaffold to scaffold (bead-to-bead transfer) was observed on corn husk scaffolds in a dynamic environment. These results suggest that decellularized harvest waste scaffolds may aid in realization of cultured meat products that will contribute to a more robust and environmentally sustainable food supply.

We used the standard comet assay successfully to generate in vitro dose-response curves under oxic and hypoxic conditions. We then made mixtures of cells that had been irradiated with 3 and 9 Gy of X-rays to simulate two subpopulations in a tumor, but efforts to accurately detect and quantify the subpopulations using the standard comet assay were unsuccessful. Therefore, we investigated a modified comet assay to determine whether it could be used for measuring hypoxia in our model systems. U251 MG cells were grown as subcutaneous tumors in athymic mice; U251 MG and U87 MG cells were grown as intracerebral (i.c.) tumors in athymic rats. Animals were injected with RSU 1069, irradiated, and euthanized. Tumors and normal brains were removed, and the cells were analyzed using a modified comet assay. Differences in comet tail moment distributions between tumor and contralateral normal brain, using tail moments at either the 25th or 50th percentile in each distribution, were taken as measures of the degree of tumor hypoxia. For U251 MG tumors, there was a positive relationship between tumor size and the degree of hypoxia, whereas preliminary data from U87 MG i.c. tumors showed less hypoxia and no apparent relationship between tumor size and hypoxia.

To facilitate investigation of the molecular mechanisms of tumor cell radiosensitivities, we have generated a set of clones with different radiosensitivities from a human glioma cell line U-251 MG-Ho. Forty-four colonies were isolated by subjecting parent cells to the mutagen N-methylnitrosourea and then irradiating these cells with increasing doses of x-rays. About half of the clones displayed different radiosensitivities than the parent cells. We selected one of the most sensitive clones (X3i) and one of the most resistant clones (Y6) for further study. Isoeffective doses for these two clones differed by about a factor of 1.7; the relative radiosensitivities of both clones were stable for at least 30 cell culture passages. These two clones do not differ significantly in either the induction or repair of radiation-induced DNA double-strand breaks as measured by pulsed field gel electrophoresis. Radiation-induced apoptosis measured by terminal deoxynucleotide transferase-mediated dUTP nick end labeling assay and micronucleus formation were similar in both clones. However, potentially lethal damage repair was greater in the radioresistant Y6 clone than in the radiosensitive X3i clone as determined by colony-forming efficiency assay.

In this commentary, the editorial team of Child Maltreatment extends and expands on APSAC's position on diversity, equity, inclusion, and justice, affirms our commitment and plans for addressing these issues in this publication, and highlights articles in this issue that continue the discussion about race and racism in the child welfare and child protection systems.

Objectives: Myasthenia gravis (MG) is an autoimmune disorder in which antibodies interfere with neuromuscular transmission. Azathioprine (AZA) is an immunosuppressant frequently used for treatment of various autoimmune conditions, including MG. The literature suggests that the rates of AZA-associated hepatotoxicity and myelosuppression in MG are highly variable. Published studies have not formally analyzed their pattern, severity, timing, and/or recovery. We assessed the prevalence, pattern and timing of AZA associated toxicity in a large group of MG patients., Methods: We identified 113 patients with MG with AZA-associated toxicity among 571 managed with this immunosuppressant. The timing of when toxicities occurred as well as pattern of laboratory abnormalities was assessed., Results: The overall prevalence of hepatotoxicity and myelosuppression was 15.2% and 9.1%, respectively. The most common pattern of hepatotoxicity seen was gamma-glutamyl transpeptidase (GGT) enzyme elevation in 67.8% of patients. Of note, 21.2% of patients with myelosuppression had normocytic anemia, 17.3% had pancytopenia, and another 17.3% developed macrocytic anemia., Conclusions: AZA-associated hepatotoxicity and myelosuppression in MG are not uncommon and may be underrecognized depending on the timing, frequency, and specific tests ordered for blood work monitoring.

Introduction: Myasthenia gravis (MG) is an autoimmune disorder characterized by autoantibodies against the postsynaptic nicotinic acetylcholine receptors, muscle-specific tyrosine kinase, low-density lipoprotein receptor-related protein 4, and agrin. The incidence of thymoma in MG is reported as ∼10%-15%. The incidence of extrathoracic metastatic thymoma is exceedingly rare and may present years after resection. Associations between thymoma and immunodeficiency have also been described, including Good syndrome., Methods and Results: We describe the clinical course, investigations, and treatments performed in a patient presenting with a myasthenic crisis in the setting of acetylcholine receptor antibody-positive generalized MG 10 years postthymectomy. Computed tomography imaging revealed 2 pancreatic lesions, but no residual thoracic thymoma. Biopsy confirmed metastatic pancreatic thymoma, which was successfully resected. His course was further complicated by cytomegalovirus retinitis with a depressed CD4 count and perniosis., Discussion: This presentation was felt to be consistent with Good immunodeficiency syndrome.

Many fishes possess specialized epidermal cells that are ruptured by the teeth of predators, thus reliably indicating the presence of an actively foraging predator. Understanding the evolution of these cells has intrigued evolutionary ecologists because the release of these alarm chemicals is not voluntary. Here, we show that predation pressure does not influence alarm cell production in fishes. Alarm cell production is stimulated by exposure to skin-penetrating pathogens (water moulds: Saprolegnia ferax and Saprolegnia parasitica), skin-penetrating parasites (larval trematodes: Teleorchis sp. and Uvulifer sp.) and correlated with exposure to UV radiation. Suppression of the immune system with environmentally relevant levels of Cd inhibits alarm cell production of fishes challenged with Saprolegnia. These data are the first evidence that alarm substance cells have an immune function against ubiquitous environmental challenges to epidermal integrity. Our results indicate that these specialized cells arose and are maintained by natural selection owing to selfish benefits unrelated to predator-prey interactions. Cell contents released when these cells are damaged in predator attacks have secondarily acquired an ecological role as alarm cues because selection favours receivers to detect and respond adaptively to public information about predation.