Effects of poloxamer-based thermo-sensitive sol-gel agent on urethral stricture after transurethral resection of the prostate for benign prostatic hyperplasia: a multicentre, single-blinded, randomised controlled trial.

OBJECTIVE: To evaluate the effectiveness of poloxamer-based thermo-sensitive sol-gel instillation, after transurethral resection of the prostate (TURP), for preventing urethral stricture. PATIENTS AND METHODS: In all, 198 patients underwent TURP for benign prostatic hyperplasia. Recruited patients were randomly divided into two groups: groups A and B. Patients in Group A (100 patients, experimental group) received poloxamer-based thermo-sensitive sol-gel instillation and patients in the Group B (98 patients, control group) received lubricant instillation after TURP. Each patient was evaluated at 4 (V1), 12 (V2), and 24 weeks (V3) after TURP. The effectiveness of poloxamer-based thermo-sensitive sol-gel instillation was evaluated based on the International Prostate Symptom Score (IPSS), IPSS-Quality of Life (QoL), Overactive bladder questionnaire (OAB-q), maximum urinary flow rate (Qmax ), post-void residual urine volume (PVR), and cystoscopy. RESULTS: Amongst the initial 198 participants, 80 patients in Group A and 83 in Group B completed the study. There were no significant differences in IPSS-QoL and OAB-q between the groups. However, Qmax was significantly different between groups A and B, at a mean (SD) of 18.92 (9.98) vs 15.58 (9.24) mL/s (P = 0.028) at 24 weeks after TURP. On cystoscopic examination, urethral stricture after TURP was found in two of the 80 patients in Group A and 10 of 83 in Group B (P = 0.023). CONCLUSIONS: Poloxamer-based thermo-sensitive sol-gel instillation after TURP lowered the incidence of urethral stricture.

Preparation of Pincer Hafnium Complexes for Olefin Polymerization.

Pincer-type [Cnaphthyl, Npyridine, Namido]HfMe2 complex is a flagship among the post-metallocene catalysts. In this work, various pincer-type Hf-complexes were prepared for olefin polymerization. Pincer-type [Namido, Npyridine, Namido]HfMe2 complexes were prepared by reacting in situ generated HfMe4 with the corresponding ligand precursors, and the structure of a complex bearing 2,6-Et2C6H3Namido moieties was confirmed by X-ray crystallography. When the ligand precursors of [(CH3)R2Si-C5H3N-C(H)PhN(H)Ar (R = Me or Ph, Ar = 2,6-diisopropylphenyl) were treated with in situ generated HfMe4, pincer-type [Csilylmethyl, Npyridine, Namido]HfMe2 complexes were afforded by formation of Hf-CH2Si bond. Pincer-type [Cnaphthyl, Sthiophene, Namido]HfMe2 complex, where the pyridine moiety in the flagship catalyst was replaced with a thiophene unit, was not generated when the corresponding ligand precursor was treated with HfMe4. Instead, the [Sthiophene, Namido]HfMe3-type complex was obtained with no formation of the Hf-Cnaphthyl bond. A series of pincer-type [Cnaphthyl, Npyridine, Nalkylamido]HfMe2 complexes was prepared where the arylamido moiety in the flagship catalyst was replaced with alkylamido moieties (alkyl = iPr, cyclohexyl, tBu, adamantyl). Structures of the complexes bearing isopropylamido and adamantylamido moieties were confirmed by X-ray crystallography. Most of the complexes cleanly generated the desired ion-pair complexes when treated with an equivalent amount of [(C18H37)2N(H)Me]+[B(C6F5)4]-, which showed negligible activity in olefin polymerization. Some complexes bearing bulky substituents showed moderate activities, even though the desired ion-pair complexes were not cleanly afforded.

A method for mandibular dental arch superimposition using 3D cone beam CT and orthodontic 3D digital model.

OBJECTIVE: The purpose of this study was to develop superimposition method on the lower arch using 3-dimensional (3D) cone beam computed tomography (CBCT) images and orthodontic 3D digital modeling. METHODS: Integrated 3D CBCT images were acquired by substituting the dental portion of 3D CBCT images with precise dental images of an orthodontic 3D digital model. Images were acquired before and after treatment. For the superimposition, 2 superimposition methods were designed. Surface superimposition was based on the basal bone structure of the mandible by surface-to-surface matching (best-fit method). Plane superimposition was based on anatomical structures (mental and lingual foramen). For the evaluation, 10 landmarks including teeth and anatomic structures were assigned, and 30 times of superimpositions and measurements were performed to determine the more reproducible and reliable method. RESULTS: All landmarks demonstrated that the surface superimposition method produced relatively more consistent coordinate values. The mean distances of measured landmarks values from the means were statistically significantly lower with the surface superimpositions method. CONCLUSIONS: Between the 2 superimposition methods designed for the evaluation of 3D changes in the lower arch, surface superimposition was the simpler, more reproducible, reliable method.