Processive cellulases are highly efficient molecular engines involved in the cellulose breakdown process. However, the mechanism that processive bacterial enzymes utilize to recruit and retain cellulose strands in the catalytic site remains poorly understood. Here, integrated enzymatic assays, protein crystallography and computational approaches were combined to study the enzymatic properties of the processive BlCel48B cellulase from Bacillus licheniformis. Hydrolytic efficiency, substrate binding affinity, cleavage patterns, and the apparent processivity of bacterial BlCel48B are significantly impacted by the cellulose size and its surface morphology. BlCel48B crystallographic structure was solved with ligands spanning -5 to -2 and +1 to +2 subsites. Statistical coupling analysis and molecular dynamics show that co-evolved residues on active site are critical for stabilizing ligands in the catalytic tunnel. Our results provide mechanistic insights into BlCel48B molecular-level determinants of activity, substrate binding, and processivity on insoluble cellulose, thus shedding light on structure-activity correlations of GH48 family members in general.Hemostasis is of great significance regardless of the smooth operation or postoperative recovery. Therefore, it is urgent to develop a hemostatic material with excellent biodegradability and biocompatibility. It is well known that both carboxymethyl chitosan and hyaluronic acid with biodegradability and biocompatibility have wound healing promoting property. Here, a degradable chitosan-based hydrogel was prepared based on carboxymethyl chitosan and cross-linked by oxidized hyaluronic acid. The hemostatic performance of the hydrogel in rat liver resection injury was evaluated which results showed that the hydrogel exhibited comparable hemostatic properties compared with Fibrin Sealant. In addition, the hydrogel proved to be rapidly absorbed by the body without significant accumulation in vivo, demonstrating good biodegradability and biocompatibility. The overall results suggested the hydrogel will be a promising hemostatic hydrogel for controlling bleeding.HLA antibodies are typically produced after exposure to transplanted tissue, pregnancy, and blood products. Sensitization delays access to transplantation and preclude utilization of donor organs. Infections and vaccinations have also been reported to result in HLA antibody formation. Adavosertib It is not known if patients develop HLA antibodies after infection with SARS-CoV-2. Here we analyzed a series of eighteen patients waiting for kidney transplantation who had symptomatic COVID-19 disease and recovered. None of the patients in this initial series developed de novo HLA antibodies. Notably, there was no increase in preexisting HLA antibodies in four highly sensitized patients with a CPRA > 80%. These preliminary data suggest that there may not be a need to repeat HLA antibody testing or perform a physical crossmatch on admission serum before kidney transplant for COVID-19 recovered patients. Data from a large number of patients with different demographics needed.Oxalate is a metabolite promoting the formation of calcium oxalate crystals in urine. Hyperoxaluria is a feature of genetic diseases, known as primary hyperoxaluria, leading to chronic kidney disease. Ethylene glycol poisoning induces the crystallization of calcium oxalate crystals in renal tubules, promoting acute renal failure. Urine oxalate results from glyoxylate transformation to oxalate in the liver, due to lactate dehydrogenase (LDH) activity, especially the LDH-5 isoenzyme. Genetic RNA interference therapy targeting lactate dehydrogenase lowers urine oxalate excretion in murine models. Stiripentol is a drug inhibiting neuronal LDH-5 isoenzyme activity. We hypothesized that stiripentol would also reduce hepatic oxalate production and urine oxalate excretion. In vitro Stiripentol decreases oxalate synthesis by hepatocytes. In vivo, stiripentol decreases urine oxalate excretion in rats and protects kidney tissue and function against ethylene glycol intoxication and hydroxyproline-induced calcium oxalate crystalline nephropathy. The use of stiripentol in clinical practice deserves further clinical studies.Kidney stone disease comprising nephrolithiasis and nephrocalcinosis is a clinical syndrome of increasing prevalence with remarkable heterogeneity. Stone composition, age of manifestation, rate of recurrence, and impairment of kidney function varies with underlying etiologies. While calcium-based kidney stones account for the vast majority their etiology is still poorly understood. Recent studies underline the notion that genetic susceptibility together with dietary habits constitutes the major driver of kidney stone formation. In addition to single gene (Mendelian) disorders, which are most likely underestimated in the adult population, common risk alleles explain part of the observed heritability. Interestingly, identified GWAS loci often match those of Mendelian disease genes and vice versa (CASR, SLC34A1, CYP24A1). These findings provide mechanistic links related to renal calcium homeostasis, vitamin D metabolism, and CaSR-signaling regulated by the CaSR-CLDN14-CLDN16/19 axis (paracellular Ca2+ reabsorption) and TRPV5 (transcellular Ca2+ reabsorption). Recent identification of new single gene disorders of calcium-oxalate-nephrolithiasis (SLC26A1, CLDN2) and distal renal tubular acidosis with nephrocalcinosis (FOXI1, WDR72, ATP6V1C2) enabled additional insights into the kidney-gut axis and molecular prerequisites of proper urinary acidification. Implementation of centralized patient registries on hereditary kidney stone diseases are necessary to build up well characterized cohorts for urgently needed clinical studies.In kidney transplantation, the assessment of individual risks remains highly imperfect and highlights the need for robust noninvasive biomarkers with the overall goal to improve patient and graft outcomes. In the field of noninvasive biomarkers discovery, urinary biomarkers are promising tools which use easily accessible biological fluid. During the past decades, the technical revolution in the fields of genetics and molecular biology, and advances in chemistry and data analysis have led to a wealth of studies using urinary cell pellets or supernatants from kidney transplant recipients. Transcriptomic, proteomic and metabonomic analyses have suggested numerous signatures for the diagnoses of acute rejection, delayed-graft function or interstitial fibrosis. Nevertheless, the translation and validation of exploratory findings and their implementation into standard clinical practice remain challenging. This requires dedicated prospective interventional trials demonstrating that the use of these biomarkers avoids invasive procedures and improves patient or transplant outcomes.Adavosertib
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