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Malaria is one of the most prevalent diseases worldwide with high incidence and mortality. Among the five species that can infect humans, Plasmodium ovale morphologically resembles Plasmodium vivax, resulting in misidentification and confusion in diagnosis, and is responsible for malarial disease relapse due to the formation of hypnozoites. P. ovale receives relatively less attention compared to other major parasites, such as P. falciparum and P. vivax, primarily due to its lower pathogenicity, mortality rates, and prevalence rates. To efficiently produce lactate dehydrogenase (LDH), a major target for diagnosing malaria, this study used three Escherichia coli strains, BL21(DE3), BL21(DE3)pLysS, and Rosetta(DE3), commonly used for recombinant protein production. These strains were characterized to select the optimal strain for P. ovale LDH (PoLDH) production. Gene cloning for recombinant PoLDH production and transformation of the three strains for protein expression were performed. The optimal PoLDH overexpression and washing buffer conditions in nickel-based affinity chromatography were established to ensure high-purity PoLDH. The yields of PoLDH expressed by the three strains were as follows: BL21(DE3), 7.6 mg/L; BL21(DE3)pLysS, 7.4 mg/L; and Rosetta(DE3), 9.5 mg/L. These findings are expected to be highly useful for PoLDH-specific diagnosis and development of antimalarial therapeutics. [ABSTRACT FROM AUTHOR]

Effect of stimulation of glucokinase (GK) export from the nucleus by small amounts of sorbitol on hepatic glucose flux in response to elevated plasma glucose was examined in 6-h fasted Zucker diabetic fatty rats at 10 wk of age. Under basal conditions, plasma glucose, insulin, and glucagon were ~8 mM, 2,000 pmol/l, and 60 rig/l, respectively. Endogenous glucose production (EGP) was 44 [+ or -] 4 [micro]mol*[kg.sup.-l]*[min.sup.-1]. When plasma glucose was raised to ~17 raM, GK was still predominantly localized with its inhibitory protein in the nucleus. EGP was not suppressed. When sorbitol was infused at 5.6 and 16.7 [micro]mol*[kg.sup.-l]*[min.sup.-1], along with the increase in plasma glucose, GK was exported to the cytoplasm. EGP (23 [+ or -] 19 and 12 [+ or -] 5 [micro]mol*[kg.sup.-1]*[min.sup.-1]) was suppressed without a decrease in glucose 6-phosphatase flux (145 [+ or -] 23 and 126 [+ or -] 16 vs. 122 [+ or -] 10 [micro]mol*[kg.sup.-l]*[min.sup.-1] without sorbitol) but increased in glucose phosphorylation as indicated by increases in glucose recycling (122 [+ or -] 17 and 114 [+ or -] 19 vs. 71 [+ or -] 11 [micro]mol*[kg.sup.-l]*[min.sup.-1]), glucose-6-phosphate content (254 [+ or -] 32 and 260 [+ or -] 35 vs. 188 [+ or -] 20 nmol/g liver), fractional contribution of plasma glucose to uridine 5'-diphosphateglucose flux (43 [+ or -] 8 and 42 [+ or -] 8 vs. 27 [+ or -] 6%), and glycogen synthesis from plasma glucose (20 [+ or -] 4 and 22 [+ or -] 5 vs. 9 [+ or -] 4 [micro]mol glucose/g liver). The decreased glucose effectiveness to suppress EGP and stimulate hepatic glucose uptake may result from failure of the sugar to activate GK by stimulating the translocation of the enzyme. obese-type 2 diabetes; glucokinase regulatory protein

Background: Although pancreatic islet transplantation is becoming an effective therapeutic option for patients with type 1 diabetes (T1D) who suffer from a substantially impaired awareness of hypoglycemia, its application is limited due to the lack of donors. Thus, pig‐to‐human islet xenotransplantation has been regarded as a promising alternative due to the unlimited number of "donor organs." Long‐term xenogeneic islet graft survival in pig‐to‐non‐human primate (NHP) models has mainly been achieved by administering the anti‐CD154 mAb‐based immunosuppressant regimen. Since the anti‐CD154 mAb treatment has been associated with unexpected fatal thromboembolic complications in clinical trials, the establishment of a new immunosuppressant regimen that is able to be directly applied in clinical trials is an urgent need. Methods: We assessed an immunosuppressant regimen composed of clinically available agents at porcine islet transplantation in consecutive diabetic NHPs. Results: Porcine islet graft survival in consecutive diabetic NHPs (n = 7; >222, >200, 181, 89, 62, 55, and 34 days) without severe adverse events. Conclusion: We believe that our study could contribute greatly to the initiation of islet xenotransplantation clinical trials. [ABSTRACT FROM AUTHOR]