Evaluating the effects of preoperative treatment with 5-alpha reductase inhibitors in holmium laser enucleation of the prostate

INTRODUCTION AND AIM

Patients treated with HoLEP are frequently treated with previous treatments, including 5-alpha-reductase inhibitors (5-ARIs). We investigated the impact of pretreatment with 5-ARIs on perioperative and immediate postoperative parameters in patients treated with HoLEP.

MATERIAL AND METHODS

A retrospective study was performed using a prospectively collected database including all patients treated with HoLEP at our center between January 2017 and January 2023. The resected tissue weight, enucleation and morcellation efficiency (enucleation weight/time and morcellation weight/ time), postoperative complications, hospital stay and hemoglobin drop have been analyzed.

RESULTS

A total of 327 patients were included. Of these, 173 (52.9%) were treated with 5-ARIs. No differences were found among the perioperative parameters investigated to determine efficiency. No differences were observed in peri- or postoperative complications, hospital stay or hemoglobin drop.

CONCLUSIONS

Therapy with 5-ARIs had no impact on the immediate postoperative outcomes of patients treated with HoLEP. In our cohort, we observed that the use of 5-ARIs did not affect surgical efficiency, enucleation or morcellation. Further multicenter studies will be necessary to validate these findings.

UDP-N-trifluoroacetylglucosamine as an alternative substrate in N-acetylglucosaminyltransferase reactions

The synthesis of UDP-N-trifluoroacetylglucosamine [uridine 5'-(2-trifluoroacetamido-2-deoxy-alpha-D-glucopyranosyl diphosphate, UDP-GlcNAc-F3] is reported. The compound is found to serve as a substrate for the core-2 GlcNAc transferase (EC 2.4.1.102) that is involved in the biosynthesis of O-linked glycoproteins and for the GlcNAcT-V transferase (EC 2.4.1.155) that is a key biosynthetic enzyme controlling the branching pattern of cell surface complex Asn-linked oligosaccharides. The trisaccharide beta-D-Galp-(1-->3) -[beta-D-GlcpNAc-F3(1-->6)] alpha-D-GalpNAc-OR [R = (CH2)8CO2Me] was prepared from beta-D-Galp-(1-->3) -alpha-D- GalpNAc-OR using the core-2 GlcNAc transferase. The tetrasaccharide beta-D-GlcpNAc-(1 -->2)-[beta-D-GlcpNAc-F3-(1-->6)]-alpha-D-Manp-(1-->6)-beta-D-Glcp -OR [R = (CH2)7CH3] using the GlcNAcT-V transferase. Removal of the trifluoroacetyl group was achieved under mild basic conditions to give the corresponding glucosamine containing tetrasaccharide. These examples demonstrate the feasibility of introducing masked forms of glucosamine residues into oligosaccharides using GlcNAc-specific transferases. The requirement for the trifluoroacetamido group as a specific recognition element was evident in the observation that neither UDP-glucosamine nor UDP-glucose served as a donor substrates for the core-2 GlcNAc transferase.

Properties and kinetic analysis of UDP-glucose dehydrogenase from group A streptococci. Irreversible inhibition by UDP-chloroacetol

UDP-glucuronic acid is used by many pathogenic bacteria in the construction of an antiphagocytic capsule that is required for virulence. The enzyme UDP-glucose dehydrogenase catalyzes the NAD+-dependent 2-fold oxidation of UDP-glucose and provides a source of the acid. In the present study the recombinant dehydrogenase from group A streptococci has been purified and found to be active as a monomer. The enzyme contains no chromophoric cofactors, and its activity is unaffected by the presence of EDTA or carbonyl-trapping reagents. Initial velocity and product inhibition kinetic patterns are consistent with a bi-uni-uni-bi ping-pong mechanism in which UDP-glucose is bound first and UDP-glucuronate is released last. UDP-xylose was found to be a competitive inhibitor (Ki, 2.7 microM) of the enzyme. The enzyme is irreversibly inactivated by uridine 5'-diphosphate-chloroacetol due to the alkylation of an active site cysteine thiol. The apparent second order rate constant for the inhibition (ki/Ki) was found to be 2 x 10(3) mM-1 min-1. Incubation with the truncated compound, chloroacetol phosphate, resulted in no detectable inactivation when tested under comparable conditions. This supports the notion that uridine 5'-diphosphate-chloroacetol is bound in the place of UDP-glucose and is not simply acting as a nonspecific alkylating agent.