Publications by authors named "Jody L Janecek"

During diabetes progression, β-cell dysfunction due to loss of potassium channels sensitive to ATP, known as KATP channels, occurs, contributing to hyperglycemia. The aim of this study was to investigate if KATP channel expression or activity in the nervous system was altered in a high-fat diet (HFD)-fed mouse model of diet-induced obesity. Expression of two KATP channel subunits, Kcnj11 (Kir6.

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Cell-based therapies hold promise for many chronic conditions; however, the continued need for immunosuppression along with challenges in replacing cells to improve durability or retrieving cells for safety are major obstacles. We subcutaneously implanted a device engineered to exploit the innate transcapillary hydrostatic and colloid osmotic pressure generating ultrafiltrate to mimic interstitium. Long-term stable accumulation of ultrafiltrate was achieved in both rodents and nonhuman primates (NHPs) that was chemically similar to serum and achieved capillary blood oxygen concentration.

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During diabetes, β-cell dysfunction due to loss of potassium channels sensitive to ATP, known as K channels occurs progressively over time contributing to hyperglycemia. K channels are additionally present in the central and peripheral nervous systems and are downstream targets of opioid receptor signaling. The aim of this study is to investigate if K channel expression or activity in the nervous system changes in diabetic mice and if morphine antinociception changes in mice fed a high fat diet (HFD) for 16 weeks compared to controls.

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Pluripotent stem (PS) cells enable the scalable production of tissue-specific derivatives with therapeutic potential for various clinical applications, including muscular dystrophies. Given the similarity to human counterparts, the non-human primate (NHP) is an ideal preclinical model to evaluate several questions, including delivery, biodistribution, and immune response. While the generation of human-induced PS (iPS)-cell-derived myogenic progenitors is well established, there have been no data for NHP counterparts, probably due to the lack of an efficient system to differentiate NHP iPS cells towards the skeletal muscle lineage.

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Although human islet transplantation has proven to provide clinical benefits, especially the near complete amelioration of hypoglycemia, the supply of human islets is limited and insufficient to meet the needs of all people that could benefit from islet transplantation. Porcine islets, secreting insulin nearly identical to that of human insulin, have been proposed as a viable supply of unlimited islets. Further, encapsulation of the porcine islets has been shown to reduce or eliminate the use of immunosuppressive therapy that would be required to prevent rejection of the foreign islet tissue.

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An orally active vaccine capable of boosting SARS-CoV-2 immune responses in previously infected or vaccinated individuals would help efforts to achieve and sustain herd immunity. Unlike mRNA-loaded lipid nanoparticles and recombinant replication-defective adenoviruses, replicating vesicular stomatitis viruses with SARS-CoV-2 spike glycoproteins (VSV-SARS2) were poorly immunogenic after intramuscular administration in clinical trials. Here, by G protein trans-complementation, we generated VSV-SARS2(+G) virions with expanded target cell tropism.

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The obesity epidemic significantly contributes to overall morbidity and mortality. Bariatric surgery is the gold standard treatment for obesity and metabolic dysfunction, yet the mechanisms by which it exerts metabolic benefit remain unclear. Here, we demonstrate a model of vertical sleeve gastrectomy (VSG) in nonhuman primates (NHP) that mimics the complexity and outcomes in humans.

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Background: C-peptide concentration is widely used as a marker of insulin secretion and is especially relevant in evaluating islet graft function following transplantation, because its measurement is not confounded by the presence of exogenous insulin. To address the shortage of human islet donors, the use of porcine islets has been proposed as a possible solution and the stringent pig-to-non-human primate (NHP) model is often the most relevant for pre-clinical evaluation of the potential for diabetes reversal resulting from an islet xenograft. The Millipore radioimmunoassay (RIA) was exclusively used to measure porcine C-peptide (PCP) until 2013 when the assay was discontinued and subsequently a commercially available enzyme-linked immunosorbent assay (ELISA) from Mercodia has been widely adopted.

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Background: Pre-clinical demonstration of porcine islet graft function is necessary to support the clinical transplantation of pig islets. C-peptide concentration is an especially useful marker of insulin secretion, because its measurement is not confounded by the presence of exogenous insulin. To measure porcine C-peptide (PCP), researchers in the field exclusively used the Millipore (previously Linco Research) radioimmunoassay (RIA) until 2011, when Mercodia released an alternative enzyme-linked immunosorbent assay (ELISA).

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Diabetes is induced in mice by using streptozotocin (STZ), a compound that has a preferential toxicity toward pancreatic β cells. We evaluated nude male mice from various sources for their sensitivity to a single high dose (160 to 240 mg/kg) of STZ. Diabetes was induced in male mice (age: median, 12 wk; interquartile range, 11 to 14 wk; body weight, about 30 g) from Taconic Farms (TAC), Jackson Laboratories (JAX), and Charles River Laboratories (CRL).

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