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Quantum electron microscopy (QEM) is a measurement approach that could reduce sample radiation damage, which represents the main obstacle to sub-nanometer direct imaging of molecules in conventional electron microscopes. This method is based on the exploitation of interaction-free measurements in an electron resonator. In this work, we present the design of a linear resonant electron cavity, which is at the core of QEM. We assess its stability and optical properties during resonance using ray-tracing electron optical simulations. Moreover, we analyze the issue of spherical aberrations inside the cavity and we propose and verify through simulation two possible approaches to the problem. Finally, we discuss some of the important design parameters and constraints, such as conservation of temporal coherence and effect of alignment fields., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this study, we investigated the effect of hydrocarbon species composition on carbon nanotube (CNT) growth using an iron catalyst by chemical vapor deposition. The atomic hydrogen and active carbon species from hydrocarbon affect to the nucleation and growth of CNT arrays. With increasing atomic hydrogen content, the interface layer distance of the CNTs decreased from 3.7 to 3.4 Å. The shifts in the G-band in the Raman spectra of the CNTs indicated that the hydrogen atoms affected the generation of C-C bonds in graphene layers., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Biological materials are the result of years of evolution and possess a number of efficient features and structures. Researchers have investigated the possibility of designing biomedical structures that take advantage of these structural features. Insect shells, such as beetle shells, are among the most promising types of biological material for biomimetic development. However, due to their intricate geometries and small sizes, it is challenging to measure the mechanical properties of these microscale structures. In this study, we developed an in-situ testing platform for site-specific experiments in a focused ion beam (FIB) system. Multi-axis nano-manipulators and a micro-force sensor were utilized in the testing platform to allow better results in the sample preparation and data acquisition. The entire test protocol, consisting of locating sample, ion beam milling and micro-mechanical bending tests, can be carried out without sample transfer or reattachment. We used our newly devised test platform to evaluate the micromechanical properties and structural features of each separated layer of the beetle horn shell. The Young's modulus of both the exocuticle and endocuticle layers was measured. We carried out a bending test to characterize the layers mechanically. The exocuticle layer bent in a brick-like manner, while the endocuticle layer exhibited a crack blunting effect., Statement of Significance: This paper proposed an in-situ manipulation/test method in focused ion beam for characterizing micromechanical properties of beetle horn shell. The challenge in precise and accurate fabrication for the samples with complex geometry was overcome by using nano-manipulators having multi-degree of freedom and a micro-gripper. With the aid of this specially designed test platform, bending tests were carried out on cantilever-shaped samples prepared by focused ion beam milling. Structural differences between exocuticle and endocuticle layers of beetle horn shell were explored and the results provided insight into the structural advantages of each biocomposite structure., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Background: The purpose of this study was to evaluate the long-term swallowing function in patients with vertical hemipharyngolaryngectomy (VHPL) for hypopharyngeal cancer., Methods: A retrospective review of 30 patients followed for more than 2 years with VHPL between 1998 and 2011 was performed., Results: Five patients (16.7%) experienced gastrostomy tube placement, 4 patients (13%) had pharyngoesophageal stricture, and 13 patients (45%) had aspiration pneumonia. There was a significant difference in the fraction of gastrostomy tube placement among type II VHPL (35.7%), type I VHPL (0%), and type III VHPL (0%; p = .014). Gastrostomy tube dependence was significantly associated with flap size (larger than 70 cm(2) ; p = .043) and aspiration pneumonia (p = .009). A significant positive correlation was found between current smokers and aspiration pneumonia (p = .030)., Conclusion: Type II VHPL, large flap reconstruction, and aspiration pneumonia had predictable values for gastrostomy tube dependence. Smoking status correlated with aspiration pneumonia. Better counseling and vigilance concerning swallowing difficulties may be possible., (© 2015 Wiley Periodicals, Inc.)

The objective of this study was to investigate the efficacy of early management of post-thyroidectomy unilateral vocal cord palsy (UVCP) and the clinical utility of the thyroidectomy-related voice questionnaire (TVQ) when planning UVCP treatment. The study group comprised 48 consecutive patients diagnosed with UVCP after thyroidectomy. Laryngoscopic examination and voice analysis were conducted, and the TVQ was administered pre-thyroidectomy and at 2 weeks and 1, 3, 6, and 12 months post-thyroidectomy. Twenty-five patients with aspiration symptoms and severe vocal difficulties received injection laryngoplasty, and 23 with no aspiration symptoms and relatively mild vocal difficulties underwent voice therapy. We performed a video fluoroscopic swallowing study on each patient 2 weeks after thyroidectomy and 1 month following the procedure. The average total TVQ scores 2 weeks post-thyroidectomy were 51.92 ± 11.42 in the injection laryngoplasty group and 35.78 ± 12.99 in the voice therapy group. Both subjective and objective parameters improved significantly at 1 month after treatment and continued to improve slowly over the next 12 months (p < 0.01) in both groups. TVQ scores were significantly lower in the injection laryngoplasty group than in the voice therapy group 1 month post-intervention (p < 0.01). At the study end point, the greatest improvement in subjective symptoms occurred in temporary VCP patients who underwent injection laryngoplasty. The optimal TVQ score cut-off distinguishing the two groups was 45 (68.0 % sensitivity, 78.3 % specificity). In conclusion, early management following timely diagnosis of post-thyroidectomy UVCP can improve symptoms within 1 month. Moreover, application of TVQ will aid clinicians to plan treatment for postoperative VCP patients.

(18)F-FDG PET/CT is clinically useful in the initial staging and follow-up of patients with head and neck squamous cell carcinoma (HNSCC). We studied the potential prognostic significance of preoperative (18)F-FDG PET/CT in HNSCC. The medical records of 294 patients who underwent preoperative (18)F-FDG PET/CT for HNSCC were retrospectively reviewed. The median SUVmax of the primary lesions (SUVmax-p) and cervical lymph nodes (SUVmax-n) was 7.98 ± 5.04 (range 1.2-28.7) and 3.34 ± 3.70 (range 1.0-20.4), respectively. There was a significant difference between with and without recurrence in SUVmax-p (11.14 ± 5.36 vs. 6.78 ± 4.35, p < 0.001) and SUVmax-n (5.60 ± 4.22 vs. 1.75 ± 1.46, p < 0.001). The cut-off values of SUVmax-p and SUVmax-n in the context of recurrence and cancer-related death were 8.5 and 3.5. The 5-year disease-free survival of patients with SUVmax-p < 8.5 and SUVmax-n < 3.5 was 79 and 79%, respectively, whereas that of patients with SUVmax-p ≥ 8.5 and SUVmax-n ≥ 3.5 was 39 and 30 %, respectively. Multivariate analysis confirmed the significant association between 5-year disease-free survival and SUVmax-p ≥ 8.5 (hazard ratio (HR) 2.68, p < 0.001) and SUVmax-n ≥ 3.5 (HR 2.29, p = 0.007). Furthermore, SUVmax-p ≥ 8.5 (HR 3.20, p = 0.012) and SUVmax-n ≥ 3.5 (HR 2.14, p < 0.001) were associated with 5-year overall survival. (18)F-FDG PET/CT cut-off values of SUVmax-p ≥ 8.5 or SUVmax-n ≥ 3.5 are associated with a recurrence and survival in HNSCC.

Conclusion: (18)F-FDG PET/CT is a useful technique for the evaluation of paraglottic space invasion and lymph node metastasis in patients with supracricoid partial laryngectomy (SCPL). Primary SUVmax values (using 7.0 as a cut-off) and nodal SUVmax values (using 2.2 as a cut-off) are important for recurrence and poor prognosis., Objectives: The purpose of this study was to evaluate the usefulness of (18)F-FDG PET/CT for paraglottic space invasion and lymph node metastasis and the prognostic significance in SCPL., Methods: The medical records of 42 patients who underwent (18)F-FDG PET/CT for SCPL before surgery were reviewed., Results: The median primary SUVmax was 6.63 ± 5.07 and the median nodal SUVmax was 1.25 ± 1.86. The primary SUVmax values with paraglottic space invasion (8.34 ± 5.92) and without (4.57 ± 2.74) were significantly different (p = 0.015). The (18)F-FDG PET/CT had an accuracy of 87% for the identification of cervical metastases on a level-by-level basis. A median primary SUVmax value of 7.0 and nodal SUVmax of 2.2 were associated with recurrence (p = 0.022 and p = 0.009, respectively) and 5-year disease-specific survival (p = 0.021 and p = 0.041, respectively).

Objective: To survey cases of benign prostatic hyperplasia (BPH) among patients visiting urologists with lower urinary tract symptoms (LUTS) at general hospitals in Korea and to investigate treatment outcomes in current clinical practice., Methods: This was a multicenter, prospective study conducted in 18 urology centers in Korea. The symptoms of BPH were observed via the International Prostate Symptoms Score (IPSS), transrectal ultrasonography, uroflometry, prostate, specific, antigen, PSA) and postvoid residual volume at the baseline, 1 week, 4 weeks, 12 weeks, 24 weeks, and 52 weeks after initial evaluation. The patients were divided into three groups according to age (group I: 50-59; group II: 60-69; group III: 70 years or older)., Results: Of the 1054 screened men, 966 were enrolled and 917 were diagnosed with BPH. Total IPSS and storage subscores were significantly higher in group III than in group II or I. By month 12, significant improvements on total IPSS and voiding subscores were demonstrated in group I over groups II and III (P = .02. 03, respectively). The incidence of dual combination therapy was significantly higher in the patients whose prostate volume was ≥30 mL and whose PSA was ≥1.5., Conclusion: At the initial visit, patients with LUTS/BPH, especially those who were relatively young, visited urologic centers because of to voiding symptoms rather than storage symptoms. In contrast, elderly men who visited the urologic centers complained not only of voiding symptoms but also storage symptoms. However, at 12 months' follow up, all of the age groups showed improvement in both storage and voiding symptoms., (Copyright © 2012 Elsevier Inc. All rights reserved.)

This experiment was performed to investigate whether apigenin has hypnotic effects and/or enhances pentobarbital-induced sleep behaviors through the GABAergic systems. Apigenin prolonged sleep time induced by pentobarbital similar to muscimol, a GABA(A) receptors agonist. Apigenin also increased sleep rate and sleep time in the combined administration with pentobarbital at the sub-hypnotic dosage, and showed synergic effects with muscimol in potentiating sleep onset and enhancing sleep time induced by pentobarbital. In addition, both of apigeinin and pentobarbital increased chloride influx in primary cultured cerebellar granule cells. Apigenin increased glutamate decarboxylase (GAD) and had no effect on the expression of GABA(A) receptor α-, β-, γ-subunits in n hippocampus of mouse brain, showing different expression of subunits from pentobarbital treatment group. In conclusion, it is suggested that apigenin augments pentobarbital-induced sleep behaviors through chloride ion channel activation.

This study was performed to investigate whether magnolol enhances pentobarbital-induced sleeping behaviors through the GABAergic systems. Magnolol prolonged the sleeping time induced by pentobarbital. In addition, magnolol increased chloride influx in primary cultured cerebellar granule cells. The expression of the GABA(A) receptor alpha-subunit was increased selectively by magnolol, but magnolol had no effect on the abundance of beta- or gamma-subunits. The expression of glutamic acid decarboxylase (GAD) was not influenced by magnolol. It is suggested that magnolol may enhance pentobarbital-induced sleeping behaviors through the activation of GABAergic systems.

Objective: The objective of this study was to evaluate the usefulness of virtual cystoscopy of the contrast material-filled bladder in evaluating patients with gross hematuria., Subjects and Methods: Seventy-three consecutive patients who had gross hematuria and whose upper urinary tracts had a normal appearance on single-detector helical CT scans were prospectively evaluated with virtual cystoscopy. Source CT data for virtual cystoscopy were obtained on a multidetector CT scanner with 1.25-mm slice thickness and transferred to a workstation for interactive navigation using volume rendering. Two radiologists independently interpreted the virtual cystoscopic images, and discrepancies were resolved by consensus. All patients also underwent conventional cystoscopy. We assessed the agreement between the findings on virtual and conventional cystoscopy. Using conventional cystoscopy as the gold standard, we evaluated the usefulness of virtual cystoscopy as an aid in identifying bladder lesions and detecting abnormal bladders., Results: Virtual cystoscopy depicted 60 lesions in the bladders of 43 patients. Fifty-six lesions (in 41 bladders) revealed on virtual cystoscopy were true-positive findings. Four lesions in two bladders with abnormal findings were false-positive. On virtual cystoscopy, the radiologists missed three lesions in two abnormal bladders that were identified on conventional cystoscopy. On virtual cystoscopy, 15 (88%) of 17 lesions smaller than 0.5 cm were identified. The agreement between the findings of virtual and conventional cystoscopy was excellent in the reviewers' identification of bladder lesions (kappa = 0.83) and detection of abnormal bladders (kappa = 0.89). The sensitivity and specificity of virtual cystoscopy were 95% and 87% for identifying bladder lesions and 95% and 93% for detecting abnormal bladders., Conclusion: Virtual cystoscopy of the contrast material-filled bladder is useful for the evaluation of the bladder in patients with gross hematuria.

Objective: The purpose of our study was to differentiate subtypes of renal cell carcinoma on helical CT scans., Materials and Methods: We reviewed CT scans of four subtypes of renal cell carcinoma: 76 conventional (clear cell), 19 papillary, 13 chromophobe, and two collecting duct. Biphasic CT scans (unenhanced, corticomedullary, and excretory phase scans) were obtained in 61 patients, and monophasic CT scans (unenhanced and excretory phase scans) in 49. We compared patient age and sex; tumor size; degree and pattern (homogeneous, heterogeneous, predominantly peripheral) of enhancement; presence or absence of calcification; and tumor-spreading patterns including perinephric change, venous invasion, and lymphadenopathy in four subtypes., Results: Conventional renal carcinoma showed stronger enhancement than the other subtypes (p < 0.05): 106 +/- 48 H (mean +/- SD) in the corticomedullary phase and 62 +/- 25 H in the excretory phase. The sensitivity and specificity for differentiating conventional renal carcinoma from the other subtypes were 74% and 100% when 84 H was used as the cutoff value in the corticomedullary phase and 84% and 91% when 44 H was used as the cutoff value in the excretory phase. Conventional (84%), papillary (74%), and collecting duct (100%) renal carcinomas tended to show heterogeneous or predominantly peripheral enhancement, whereas chromophobe renal carcinoma (69%) usually showed homogeneous enhancement. Calcification was more common in papillary (32%) and chromophobe (38%) renal carcinomas than in conventional renal carcinoma (11%) (p < 0.05). Perinephric change and venous invasion were not noted in chromophobe renal carcinoma, whereas both were common in collecting duct renal carcinoma., Conclusion: For the differentiation of the subtypes of renal cell carcinoma, degree of enhancement is the most valuable parameter; enhancement pattern, the presence or absence of calcification, and tumor-spreading patterns can serve supplemental roles in the identification of the subtype of renal cell carcinoma.

The authors reported a case of ectopic paragonimiasis in a 40 year old Korean housewife who came to the hospital because of abdominal mass and pain. She was proved to have multiple parasitic granulomas involving lung, uterus, uterine tube and subcutaneous tissue. The ovary was also the site of parasitism. The past history revealed an episode of ingestion of fresh water crabs soaked in soybean sauce which were obtained in a market of Seoul City 2 years prior to the present illness. The patient was treated for tuberculosis for a year without confirmation of etiologic agent. After surgical removal of all abdominal and most of pelvic granulomas, the patient was treated with praziquantel 25 mg/kg t.i.d. for 3 days, and was judged to be cured after 4 months.