Rabbit model of tracheal stenosis using cylindrical diffuser.

BACKGROUND AND OBJECTIVE: Variable methods of animal model have been introduced to develop tracheal stenosis. However, none of the prior models allow for predictable determination of the grade of stenosis. This study sought to establish an animal model of tracheal stenosis by using a cylindrical diffuser and to evaluate the feasibility of a reproducible model. STUDY DESIGN/MATERIALS AND METHODS: A cylindrical diffuser was developed to have a 5 mm active segment to emit laser light circumferentially. Twenty one New Zealand white rabbits were enrolled in this study. The cylindrical diffuser was inserted transorally under bronchoscopic view and the diffused light was delivered to tracheal mucosa 2 cm below the level of vocal cord. Input power of irradiation was 10 W, 5 seconds in group A (n = 7), 10 W, 7 seconds in group B (n = 7), and 8 W, 5 seconds in group C (n = 7). The degree of tracheal stenosis was observed weekly and the rabbits were euthanized 4 weeks after the laser irradiation. RESULTS: The degree of stenosis in group B (90-98%) was significantly larger than that of group A (75-92%) (P = 0.004), while degree in group C (24-35%) was significantly smaller than that of group A (P < 0.001). Two rabbits of group A were euthanized at 3 weeks due to costal retraction. In group B, six rabbits died within 3 weeks after laser irradiation due to severe tracheal stenosis and tracheal malacia, while one rabbit was euthanized 16 days after the irradiation. All rabbits in group C survived up to 4 weeks. Survival between three groups showed significant difference (P = 0.001). CONCLUSION: The degree of stenosis was significantly different according to the delivered optical energy to tracheal mucosa. Therefore, the proposed model may be used in animal studies to emulate variable grades of tracheal stenosis. Lasers Surg. Med. 49:372-379, 2017. © 2016 Wiley Periodicals, Inc.

Therapeutic effects of a novel synthetic α-secretase.

Excessive accumulation of amyloid-ß (Aß) has been associated with the pathogenesis of Alzheimer's disease (AD). Clinical studies have further proven that elimination of Aß can be a viable therapeutic option. In the current study, we conceptualized a fusion membrane protein, referred to as synthetic α-secretase (SAS), that can cleave amyloid precursor protein (APP) and Aß specifically at the α-site. In mammalian cells, SAS indeed cleaved APP and Aß at the α-site. Overexpression of SAS in the hippocampus was achieved by direct injection of recombinant adeno-associated virus serotype 9 (AAV9) that expresses SAS (AAV9-SAS) into the bilateral ventricles of mouse brains. SAS enhanced the non-amyloidogenic processing of APP, thus reducing the levels of soluble Aß and plaques in the 5xFAD mice. In addition, SAS significantly attenuated the cognitive deficits in 5xFAD mice, as demonstrated by novel object recognition and Morris water maze tests. Unlike other Aß-cleaving proteases, SAS has highly strict substrate specificity. We propose that SAS can be an efficient modality to eliminate excessive Aß from diseased brains.

Prostate volume measurement by transrectal ultrasonography: comparison of height obtained by use of transaxial and midsagittal scanning.

PURPOSE: The purpose of this study was to compare prostate volume measured by transrectal ultrasonography (TRUS) between transaxial scanning and midsagittal scanning. We tried to determine which method is superior. MATERIALS AND METHODS: A total of 968 patients who underwent TRUS for diagnosis of any diseases related to the prostate were included in this study. When measuring prostate volume by TRUS, we conducted the measurements two ways at the same time in all patients: by use of height obtained by transaxial scanning and by use of height obtained by midsagittal scanning. Prostate volume was calculated by using the ellipsoid formula ([height×length×width]×π/6). RESULTS: For prostate volume measured by TRUS, a paired t-test revealed a significant difference between using height obtained by transaxial scanning and that obtained by midsagittal scanning in all patients (28.5±10.1 g vs. 28.7±9.9 g, respectively, p=0.004). However, there were no significant differences in the prevalence of prostate volume more than 20 g (known benign prostatic enlargement [BPE]) between the two methods by chi-square test (90.5% [n=876], 90.8% [n=879], respectively; p=0.876). When analyzed in the same way, there were no significant differences in the prevalence of prostate volume more than 30 g (generally, high-risk BPE) between the two methods (34.5% [n=334], 36.3% [n=351], respectively; p=0.447). CONCLUSIONS: Although prostate volume by TRUS differed according to the method used to measure height, that is, transaxial or midsagittal scanning, we conclude that there are no problems in diagnosing BPE clinically by use of either of the two methods.

Development of solvent-free offset ink using vegetable oil esters and high molecular-weight resin.

In the development of solvent-free offset ink, the roles of resin molecular weight and used solvent on the ink performance were evaluated by examining the relationship between the various properties of resin and solvent and print quality. To find the best performing resin, the soy-oil fatty acid methyl ester (FAME) was applied to the five modified-phenolic resins having different molecular weights. It is found from the experimental results that the ink made of higher molecular weight and better solubility resin gives better printability and print quality. It is because larger molecular weight resin with better solubility gives higher rate of ink transfer. From the ink application of different esters to high molecular weight resin, the best printing performance was yielded from the soy-oil fatty acid butyl ester (FABE). It is due to its high kinematic viscosity resulting in the smallest change of ink transfer weight upon multiple number of printing, which improves the stability of ink quality.

The relationship between lower urinary tract symptoms/benign prostatic hyperplasia and the number of components of metabolic syndrome.

OBJECTIVE: To investigate the relationship between lower urinary tract symptoms (LUTS)/benign prostate hyperplasia (BPH) and a number of components of metabolic syndrome (MetS). METHODS: A total of 1224 male police officers aged 50-59 years who had participated in a health examination were included. LUTS/BPH were assessed by prostate-specific antigen, international prostate symptom score (IPSS), total prostate volume (TPV), maximum urinary flow rate (Qmax), and postvoid residual (PVR) urine volume. Testosterone levels were also examined. MetS was defined using National Cholesterol Education Program-Adult Treatment Panel III guidelines. The subjects were classified into 4 groups according to the number of exhibited MetS components (0, 1-2, 3, and 4-5). We used the Mantel-Haenszel extension test and logistic regression analyses. RESULTS: MetS was diagnosed in 29.0% of the patients. The BPH ratio (IPSS >7, TPV ≥30 mL, and/or Qmax <15 mL/sec), TPV ≥30 mL, and PVR ≥50 mL significantly increased with an increasing number of metabolic abnormalities. The odds ratio (OR) in relation to a TPV ≥30 mL and a PVR ≥50 mL significantly rose as the number of positive MetS components increased after adjusting for age and testosterone. Additionally, the ORs (adjusting for age and testosterone) in relation to BPH also increased as the number of positive MetS components increased, with a suggestive threshold effect associated with 4-5 positive components (BPH: IPSS >7 + TPV ≥30 mL; 4 and 5 components, 3.496, 1.805-6.769, P = .001; BPH: IPSS >7 + TPV ≥30 mL + Qmax <15 mL/sec; 4 and 5 components, 5.458, 1.777-16.764, P = .002). CONCLUSION: According to our results, the cases of LUTS/BPH were positively associated with the number of MetS components.

Spontaneous and serial rupture of both Achilles tendons associated with secondary hyperparathyroidism in a patient receiving long-term hemodialysis.

The spontaneous and serial rupture of the bilateral Achilles tendons without history of significant trauma is an uncommon complication in long-term hemodialysis (HD) patients. The majority of these patients have additional predisposing factors, such as previous use of fluoroquinolone antibiotics or corticosteroids. In general, this condition is associated with a coexisting systemic disease, including chronic kidney disease (CKD), secondary hyperparathyroidism, systemic lupus erythematosus (SLE), and diabetes mellitus (DM). Here, we report a 46-year-old man who had been undergoing regular HD for 11 years. He developed a spontaneous and consecutive rupture of both Achilles tendons. Based on previous reports of tendon ruptures in uremic patients and on the patient's lack of corticosteroid or fluoroquinolone use, we believe that secondary hyperparathyroidism was the predisposing factor in this patient. The mechanism seems to be related to a high parathyroid hormone (PTH) level, which results in osteolytic bone resorption at the tendon insertion site. Treatment and prevention of such tendon ruptures include early surgical repair and control of secondary hyperparathyroidism, by use of vitamin D analogs, and total parathyroidectomy, with or without autotransplantation of a parathyroid gland.

Geriatric nutritional risk index may be a significant predictor of mortality in Korean hemodialysis patients: a single center study.

Our objective was to examine the association between the Geriatric Nutritional Risk Index (GNRI) and mortality in Korean hemodialysis (HD) patients. We examined the GNRI of 120 maintenance HD patients and followed these patients for 120 months. Predictors for all-cause death were examined using life table analysis and the Cox proportional hazards model. Life table analysis revealed that subjects with a GNRI < 90 (n = 19) had a marginally lower survival rate than did those with a GNRI ≥ 90 (n = 101) (Wilcoxon test, P = 0.048). Multivariate Cox proportional hazards analyses demonstrated that the GNRI was a significant predictor of mortality (hazard ratio 0.966, 95% confidence interval 0.945-0.995, P = 0.018), after adjusting for age, sex, presence of diabetes mellitus, and body weight. These results demonstrate that the GNRI may be a significant predictor of mortality in Korean HD patients.

Herpesviridae viral infections after chemotherapy without antiviral prophylaxis in patients with malignant lymphoma: incidence and risk factors.

OBJECTIVES: The herpesviridae family includes, among others, herpes simplex virus, varicella zoster virus, Epstein-Barr virus, and cytomegalovirus. Herpesviridae viral infections (HVIs) can lead to serious complications in lymphoma patients undergoing chemotherapy. There is no consensus on the dose and duration of antiviral prophylaxis in these patients. We retrospectively analyzed the incidence and risk factors for HVI in lymphoma patients undergoing chemotherapy. METHODS: We reviewed the records of 266 patients who were newly diagnosed with lymphoma and received chemotherapy without acyclovir prophylaxis between June 1996 and August 2009. RESULTS: The cumulative incidence rate of HVI was 20.16% for 5 years from the start of chemotherapy. Independent predictive factors for HVI in lymphoma patients were: female sex [hazard ratio (HR) 2.394; 95% confidence interval (CI): 1.245-4.607; P=0.009], cumulative dose of steroids per body surface area of at least 2500 mg/m(2) (HR 7.717; 95% CI: 3.814-18.703; P<0.001), and history of neutropenic fever (HR 0.297; 95% CI: 0.150-0.588; P<0.001). CONCLUSIONS: Female sex, high dose of steroids per body surface area, and neutropenic fever were risk factors for HVI in patients with lymphoma undergoing chemotherapy without acyclovir prophylaxis.

Effects of Helicobacter pylori eradication in patients with immune thrombocytopenic purpura.

BACKGROUND: The relationship between Helicobacter pylori (H. pylori) infection and chronic idiopathic thrombocytopenic purpura (ITP) has been confirmed; however, no clear evidence for the effectiveness of H. pylori eradication on ITP exists thus far. The purpose of this study was to investigate platelet recovery in chronic ITP after H. pylori eradication. METHODS: A total of 25 patients (18 male, 7 female; the median age of 55 years) diagnosed with ITP, whose platelet counts were less than 100×10(3)/µL, were enrolled. They were tested for H. pylori infection by the rapid urea test or urea breath test. All patients received triple therapy for 7 or 14 days to eradicate H. pylori infection. RESULTS: Of the 25 patients, 23 (92%) were diagnosed with H. pylori infection. Of all the ITP patients, 11 (44%) exhibited a complete response (CR) to H. pylori eradication therapy; 6 (24%), a partial response (PR); and 8 (32%) were nonresponsive (NR). Predictive factors of response after H. pylori eradication therapy were platelet counts at the initial response (27.3% responders among patients with platelet counts <100×10(3)/µL vs 100% responders among patients with platelet counts ≥100×10(3)/µL, P<0.001) and H. pylori infectivity (73.9% responders among the H. pylori positive patients vs 0% responders among the H. pylori negative patients, P=0.032). CONCLUSION: This study confirmed the efficacy of H. pylori eradication in increasing the platelet count in ITP patients. Further studies with a larger number of patients are necessary to identify the crucial predictive factors responsible for platelet recovery in chronic ITP patients with the H. pylori infection.