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PurposeProstatic abscess is an uncommon urologic disease but has a high mortality rate if not treated properly. Furthermore, diagnosis and proper treatment of prostatic abscesses remains a challenge for physicians. Therefore, we compared data on conservative treatments, transurethral resection of prostatic abscess, and transrectal ultrasound (TRUS)-guided needle aspiration in 52 cases over a 10-year period.Materials and MethodsThe records of 52 patients diagnosed with prostatic abscess by computed tomography at Gangnam Severance Hospital between January 2000 and September 2010 were retrospectively reviewed. All patients were discharged when their leukocytosis had normalized and they had been free of fever for 2 days. Multivariate regression analysis was done to determine independent risk factors for the length of hospitalization.ResultsAt the time of diagnosis, the average age of the 52 patients was 61.3 years (range, 33 to 81 years), the average volume of the prostate was 56.3 ml (range, 21 to 223 ml), the average prostate-specific antigen was 18.54 ng/ml (range, 2.0 to 57.0 ng/ml), and the average abscess size was 3.8 cm (range, 2.1 to 5.5 cm). All patients were treated with parenteral antibiotics during their hospital stay with intravenous antibiotics (fluoroquinolone monotherapy or 3rd-generation cephalosporin in combination with an aminoglycoside). Of 52 patients, 22 had diabetes mellitus (42.3%), 19 had hypertension (36.5%), and 7 (13.5%) had paraplegia due to spinal cord injury. The most common symptoms were fever (47, 90.4%), perineal discomfort (43, 82.7%), dysuria (40, 76.9%), and urinary retention (29, 55.8%). Prostatic abscesses were treated by conservative treatment (11 cases), transurethral resection of prostatic abscess (23 cases), and TRUS-guided needle aspiration (18 cases). The average hospitalization stay was 17.5 days (range, 6 to 39 days); that of conservative treatment patients was 19.1 days (range, 9 to 39 days). Patients treated by transurethral resection of prostatic abscess and TRUS-guided needle aspiration stayed 10.2 days (range, 6 to 15 days) and 23.25 days (range, 18 to 34 days), respectively. Of the 18 cases who underwent needle aspiration, prostatic abscesses recurred in 4 cases (22.2%) within 1 month after patient discharge. The 2 patients subjected to conservative treatment died due to sepsis. We found no independent factors that affected the average hospitalization period.ConclusionsPatients with prostatic abscess treated by transurethral resection of the prostate had a significantly shorter hospitalization length compared with needle aspiration.

The van der Waals (vdW) materials with low dimensions have been extensively studied as a platform to generate exotic quantum properties [1][2][3][4][5][6]. Advancing this view, a great deal of attention is currently paid to topological quantum materials with vdW structures, which give new concepts in designing the functionality of materials. Here, we present the first experimental realization of a higher-order topological insulator by investigating a quasi-one-dimensional (quasi-1D) bismuth bromide Bi 4 Br 4 [7][8][9][10][11] built from a vdW stacking of quantum spin Hall insulators (QSHI) [12] with angle-resolved photoemission spectroscopy (ARPES). The quasi-1D bismuth halides can select various topological phases by different stacking procedures of vdW chains, offering a fascinating playground for engineering topologically non-trivial edge-states toward future spintronics applications.The Z 2 weak topological insulator (WTI) phases have been confirmed in the materials with stacked QSHI layers, where the side-surface becomes topologically non-trivial by accumulating helical edge states of QSHI layers [13,14]. Similarly, higher-order topological insulators (HOTIs) are expected to be built from stacking QSHIs, which, however, accumulate the 1D edge-states to develop 1D helical hinge-states in a 3D crystal [15,16]. Such HOTI phases have been theoretically predicted recently in materials previously regarded as trivial insulators under the Z 2 criterion by extending the topological classification to the Z 4 topological index [17][18][19][20][21][22]. To date, only one material has been experimentally confirmed to be in the higher-order topological phase, which is bulk bismuth [23]. However, bulk bismuth is a semimetal, which cannot become insulating even by carrier doping. Materials science is, therefore, awaiting the first experimental realization of a HOTI, which enables one to explore various quantum phenomena including spin currents around hinges and quantized conductance under the external fields.A quasi-1D bismuth bromide, Bi 4 Br 4 , with a bilayer structure of chains (Fig. 1b) is theoretically predicted to be a topological crystalline insulator of Z 2,2,2,4 = {0, 0, 0, 2}, protected by the C 2 -rotation symmetry [10,11,[19][20][21]. This state should develop 2D topological surface states in the cross-section (010) of the chains [24,25]. Significantly, theory also categorizes this system as a HOTI, and expects that 1D helical hinge-states emerge between the top-surface (001) and the side-surface (100) of a crystal due to the second-order bulk-boundary correspondence [10,11]. Nevertheless, the topological phase of Bi 4 Br 4 has

We investigated whether stone heterogeneity index (SHI), which a proxy of such variations, was defined as the standard deviation of a Hounsfield unit (HU) on non-contrast computed tomography (NCCT), can be a novel predictor for shock-wave lithotripsy (SWL) outcomes in patients with ureteral stones. Medical records were obtained from the consecutive database of 1,519 patients who underwent the first session of SWL for urinary stones between 2005 and 2013. Ultimately, 604 patients with radiopaque ureteral stones were eligible for this study. Stone related variables including stone size, mean stone density (MSD), skin-to-stone distance, and SHI were obtained on NCCT. Patients were classified into the low and high SHI groups using mean SHI and compared. One-session success rate in the high SHI group was better than in the low SHI group (74.3% vs. 63.9%, P = 0.008). Multivariate logistic regression analyses revealed that smaller stone size (OR 0.889, 95% CI: 0.841–0.937, P < 0.001), lower MSD (OR 0.995, 95% CI: 0.994–0.996, P < 0.001), and higher SHI (OR 1.011, 95% CI: 1.008–1.014, P < 0.001) were independent predictors of one-session success. The radiologic heterogeneity of urinary stones or SHI was an independent predictor for SWL success in patients with ureteral calculi and a useful clinical parameter for stone fragility.

We first report graphene-assisted chemical etching (GaCE) of silicon by using patterned graphene as an etching catalyst. Chemical-vapor-deposition-grown graphene transferred on a silicon substrate is patterned to a mesh with nanohole arrays by oxygen plasma etching using an anodic- aluminum-oxide etching mask. The prepared graphene mesh/silicon is immersed in a mixture solution of hydrofluoric acid and hydro peroxide with various molecular fractions at optimized temperatures. The silicon underneath graphene mesh is then selectively etched to form aligned nanopillar arrays. The morphology of the nanostructured silicon can be controlled to be smooth or porous depending on the etching conditions. The experimental results are systematically discussed based on possible mechanisms for GaCE of Si.

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Graphene/Si quantum dot (QD) heterojunction diodes are reported for the first time. The photoresponse, very sensitive to variations in the size of the QDs as well as in the doping concentration of graphene and consistent with the quantum-confinement effect, is remarkably enhanced in the near-ultraviolet range compared to commercially available bulk-Si photodetectors. The photoresponse proves to be dominated by the carriertunneling mechanism.

Possible role of metabolism by the intestinal bacteria in geniposide-induced cytotoxicity was investigated in human hepatoma HepG2 cells. Initially, toxic effects of geniposide and its metabolite genipin were compared. Genipin, a deglycosylated form of geniposide, was cytotoxic at the concentrations that geniposide was not. As metabolic activation systems for geniposide, human intestinal bacterial cultures, fecal preparation (fecalase) and intestinal microbial enzyme mix were employed in the present study. When geniposide was incubated with human intestinal bacteria, either Bifidobacterium longum HY8001 or Bacteroides fragilis, for 24 h, the cultured media caused cytotoxicity in HepG2 cells. Fecalase and intestinal enzyme mix were also effective to metabolically activate geniposide to its cytotoxic metabolite. The present results indicated that genipin, a metabolite of geniposide, might be more toxic than geniposide, and that intestinal bacteria might have a role in biotransformation of geniposide to its toxic metabolite. In addition, among three activation systems tested, intestinal microbial enzyme mix would be convenient to use in detecting toxicants requiring metabolic activation by intestinal bacteria.