Intraductal lithotripsy in sialolithiasis with two different Ho:YAG lasers: presetting parameters, effectiveness, success rates.

OBJECTIVE: To compare two different Ho:YAG laser systems in relation to the preset parameters and their effectiveness for intraductal fragmentation of the salivary stones. PATIENTS AND METHODS: We made a retrospective study in two tertiary referral centers (Department of ENT, Head and Neck Surgery, University of Erlangen-Nuremberg, Germany and the MacKay Memorial Hospital, Taipei, Taiwan). Patients with a diagnosis of sialolithiasis were treated in Erlangen and Taipei. The Erlangen patients were treated using the Calculase II™ Ho:YAG laser (Karl Storz, Tuttlingen, Germany) at 4 Hz, 1.2 J (4.8 W) and the MacKay patients were treated using the VersaPulse® PowerSuite™ Ho:YAG laser (Lumenis Ltd., Yokneam, Israel) at 6 Hz, 0.5 J (3 W). RESULTS: A total of 12 patients with 12 stones were treated in Erlangen and 54 with 75 stones in Taipei. The submandibular stones were present in 50% and 86.7% of cases, respectively. The complete fragmentation was achieved in all of the treated stones in both groups; 100% and 92.6% of the patients were stone-free, 100% and 94.4% of the patients became symptom-free, respectively. 33% of the Erlangen patients had multimodal treatments. The glands were preserved in all cases in both centers. CONCLUSIONS: The Ho:YAG laser proved to be effective in the treatment of sialolithiasis. Stone size, location, and involved gland were important additional parameters. Our experience and the literature results show that the laser presetting with a frequency of 3-6 Hz, an energy level of 0.5-1.2 J, and effective power of between 3 and 4.8 W is sufficient to achieve maximum success without any increased risk for complications.

Sudden sensorineural hearing loss is associated with chronic rhinosinusitis: population-based study.

BACKGROUND: This study aimed to evaluate the association of chronic rhinosinusitis with sudden sensorineural hearing loss using a population-based database. METHODS: Sampled subject data were obtained from the Taiwan Longitudinal Health Insurance Database 2000. A total of 3325 patients with sudden sensorineural hearing loss were identified and 9975 controls were randomly selected. A conditional logistic regression was used to calculate the odds ratio for having been previously diagnosed with chronic rhinosinusitis, for cases and controls. RESULTS AND CONCLUSION: The adjusted odds ratio of having prior chronic rhinosinusitis among cases compared to controls was 1.36 (95 per cent confidence interval = 1.16-1.60). The significant relationship between sudden sensorineural hearing loss and chronic rhinosinusitis was most pronounced among those patients aged 44 years or less (compared to controls) (odds ratio = 2.18; 95 per cent confidence interval = 1.63-2.92). However, the significant relationship between sudden sensorineural hearing loss and prior chronic rhinosinusitis was not sustained for patients older than 60 years compared to controls.

Experiences in the treatment of obstructive sialoadenitis with sialendoscopy.

PURPOSE: The success of stone removal with sialendoscopic lithotripsy in the management of lithiasis-related obstructive sialoadenitis has been reported, but the proper management for patients with non-lithiasis obstructive sialoadenitis remains unclear. This study aims to report experiences in sialendoscopy for the management of obstructive sialoadenitis with and without the presence of stones. METHODS: Data from 71 procedures in 66 patients who underwent sialendoscopy for obstructive sialoadenitis were recorded and compared in terms of clinical data, computed tomography (CT) findings, procedural techniques and outcomes. RESULTS: The overall specificity rate of CT for detecting sialolithiasis was 91.6%. The complete remission rate was 100% for patients with confirmed sialolithiasis successfully treated with stone removal after endoscopic lithotripsy. For patients with non-sialolithiasis obstructive sialoadenitis of the submandibular gland, the complete remission rate dropped to 22% if no additional treatments were done after a diagnostic sialendoscopy. If sialostents were inserted, the complete remission rate increased to 55%. However, this improvement was very limited in terms of the overall management of the affected parotid gland. CONCLUSION: For patients with obstructive sialoadenitis and salivary gland stones, removal of the stones under sialendoscopy will most likely provide complete remission. Patients without stones have much worse treatment outcomes compared to those with true sialolithiasis. Sialostent placement may have the potential to improve treatment outcomes in the management of non-lithiasis obstructive sialoadenitis.

Endoscopic Holmium:YAG laser-assisted lithotripsy: A Preliminary Report.

PROBLEM/OBJECTIVE: Laser-assisted lithotripsy under sialendoscopy has the potential to overcome the limitations of traditional sialendoscopic lithotripsy when facing salivary stones. In this preliminary study, we report our experience with Holmium:YAG laser-assisted lithotripsy. METHODS: Data from 11 Asian patients receiving sialendoscopies for laser-assisted lithotripsy performed in our department from August 2013 to June 2014 were recorded and reviewed. RESULTS: A total of 18 procedures were performed in 11 Taiwanese patients with symptoms of obstructive sialoadenitis who were diagnosed with sialolithiasis. The sizes of the stones ranged between 3 mm and 13 mm. The endoscopic lithotomy procedures were performed in all 11 patients, and stone fragmentation with the Holmium:YAG laser was done successfully in all patients. All patients were followed for a minimum of 3 months, and there was no evidence of complications or recurrences over the follow up period. CONCLUSION: The Holmium:YAG laser allowed successful fragmentation of stones in all 11 patients. Our experience with this procedure supports the use of Holmium:YAG laser-assisted lithotripsy through sialendoscopy in Asian patients.

Risk of new-onset type II diabetes after appendicectomy.

BACKGROUND: Altered immune function after appendicectomy has been associated with autoimmune disease, even though the mechanisms are not clearly elucidated. This study aimed to investigate whether the frequency of new-onset type II diabetes was increased after appendicectomy in a case-control study. METHODS: This was a retrospective cohort study from the Taiwan Longitudinal Health Insurance Database 2000. The relative risk was compared with that in the general population using population-based data. Each patient was tracked for a 3-year interval to identify those who developed type II diabetes. Cox proportional hazard regression analysis was used to assess the risk of type II diabetes during follow-up. RESULTS: A total of 31,512 patients were included in the study, of whom 5252 had an appendicectomy (study cohort) and 26,260 were matched for comparison. Some 714 patients (2.3 per cent) developed type II diabetes during the 3-year follow-up, 161 in the study cohort (3.1 per cent) and 553 in the comparison cohort (2.1 per cent). The adjusted hazard ratio (HR) for type II diabetes in the study cohort was 1.45 (95 per cent c.i. 1.22 to 1.74). This increased risk was most pronounced in men (adjusted HR 1.47, 1.16 to 1.88) and in those with a perforated appendix (adjusted HR 2.28, 1.71 to 3.03), and applied only to patients younger than 65 years of age. CONCLUSION: An increased risk of new-onset type II diabetes within 3 years after appendicectomy was found in patients aged less than 65 years. The risk was highest in men and in those with complicated appendicitis.

An unexpected route for otolaryngology bacterial contamination with a Venturi atomizer.

BACKGROUND: The Venturi-principle atomizer is a commonly used device in otolaryngology practices. The purpose of this study is to evaluate the possible route of bacterial contamination from the nasal vestibule to the atomizer tip through the jet airflow created during the use of the Venturi atomizer. METHODS: Thirty nostrils from 15 enrolled volunteers were tested. The aerosols generated by spraying sterilized saline into the nostrils were collected using a specially made aerosol-collecting nozzle cap. The collected samples were sent for bacterial culture, and nasal vestibular swab cultures were performed for comparison. RESULTS: In the aerosol-exposed group, 18 out of 30 samples (60%) were positive for bacterial growth, confirming the bacterial contamination from the nasal vestibule to the atomizer tip through the reverse jet airflow. The bacteria species in 8 of the 18 positive samples were identical to those from the nasal swab culture results from the same nostril. CONCLUSION: In ordinary otolaryngology practices, there are significant risks for bacterial contamination from the nasal vestibule to the tip of the Venturi atomizer even without direct contact. Clinicians must be more aware of this pattern of contamination, which has not been reported in the existing literature.

Epitaxial growth of graphene on 6H-silicon carbide substrate by simulated annealing method.

We grew graphene epitaxially on 6H-SiC(0001) substrate by the simulated annealing method. The mechanisms that govern the growth process were investigated by testing two empirical potentials, namely, the widely used Tersoff potential [J. Tersoff, Phys. Rev. B 39, 5566 (1989)] and its more refined version published years later by Erhart and Albe [Phys. Rev. B 71, 035211 (2005)]. Upon contrasting the results obtained by these two potentials, we found that the potential proposed by Erhart and Albe is generally more physical and realistic, since the annealing temperature at which the graphene structure just coming into view at approximately 1200 K is unambiguously predicted and close to the experimentally observed pit formation at 1298 K within which the graphene nucleates. We evaluated the reasonableness of our layers of graphene by calculating carbon-carbon (i) average bond-length, (ii) binding energy, and (iii) pair correlation function. Also, we compared with related experiments the various distance of separation parameters between the overlaid layers of graphene and substrate surface.

Head mirror versus headlight: illumination, visual identification and visual acuity for otolaryngological examination.

OBJECTIVE: To investigate and compare the performance of head mirrors and headlights during otolaryngological examination. METHODS: The illuminance and illumination field of each device were measured and compared. Visual identification and visual acuity were also measured, in 13 medical students and 10 otolaryngology specialists. RESULTS: The illuminance (mean ± standard deviation) of the LumiView, Kimscope 1 W and Kimscope 3 W headlights and a standard head mirror were 352.3 ± 9, 92.3 ± 4.5, 438 ± 15.7 and 68.3 ± 1.2 lux, respectively. The illumination field of the head mirror (mean ± standard deviation) was 348 ± 29.8 grids, significantly greater than that of the Kimscope 3 W headlight (183 ± 9.2 grids) (p = 0.0017). The student group showed no statistically significant difference between visual identification with the best headlight and the head mirror (score means ± standard deviations: 56.2 ± 9 and 53.3 ± 14.1, respectively; p = 0.3). The expert group scored significantly higher for visual identification with head mirrors versus headlights (59.7 ± 3.3 vs 55.2 ± 5.8, respectively; p = 0.0035), but showed no difference for visual acuity. CONCLUSION: Despite the advantages of headlight illumination, head mirrors provided better, shadow-free illumination. Despite no differences amongst students, head mirrors performed better than headlights in experienced hands.

Simvastatin increases osteoblasts and osteogenic proteins in ovariectomized rats.

BACKGROUND: Previous reports have indicated that statins could prevent bone loss in ovariectomized (OVX) rats and increase the expressions of osteogenic genes in cultured osteoblasts. In this study, we hypothesized that simvastatin might increase osteoblast number and protein expressions of osteogenic markers localized in bones in concomitance with the prevention of bone loss in OVX rats. MATERIALS AND METHODS: Fifty-four 3-month-old OVX and sham-operated (SHAM) female Sprague-Dawley rats were used. Simvastatin (10-20 mg kg(-1) day(-1)) was administrated orally for 6 weeks. Trabecular volume, osteoblast number and osteogenic proteins including BMP2, collagen type I and osteocalcin on bone sections obtained from lumbar vertebral body, distal femur and proximal tibia were measured. RESULTS: The results showed that SHAM rats had significantly less trabecular bone volume and osteoblast number than that of OVX rats 6 weeks after operation. Oral simvastatin treatment (10-20 mg kg(-1) day(-1)) increased bone volume and osteoblast number in the distal femurs, proximal tibiae and vertebrae of OVX rats. Furthermore, the osteoblastic cells with immuno-stained BMP2, collagen type I and osteocalcin in vertebral bones were significantly increased by simvastatin treatment (20 mg kg(-1) day(-1)) in OVX rats. CONCLUSIONS: This study demonstrates that simvastatin enhances the production of osteogenic proteins in bone and this effect may contribute to the prevention of bone loss in OVX rats.

Efficacy of a cell phone-based exercise programme for COPD.

The application of a supervised endurance exercise training programme in a home setting offering convenience and prolonged effects is a challenge. In total, 48 patients were initially assessed by the incremental shuttle walk test (ISWT), spirometry and the Short Form-12 (SF-12) quality-of-life questionnaire, and then every 4 weeks for 3 months thereafter and again after 1 yr. During the first 3 months, 24 patients in the cell phone group were asked to perform daily endurance walking at 80% of their maximal capacity by following the tempo of music from a program installed on a cell phone. The level of endurance walking at home was readjusted monthly according to the result of ISWT. In the control group, 24 patients received the same protocol and were verbally asked to take daily walking exercise at home. Patients in the cell phone group significantly improved their ISWT distance and duration of endurance walking after 8 weeks. The improvements in ISWT distance, inspiratory capacity and SF-12 scoring at 12 weeks persisted until the end of the study, with less acute exacerbations and hospitalisations. In the present pilot study, the cell phone-based system provides an efficient, home endurance exercise training programme with good compliance and clinical outcomes in patients with moderate-to-severe chronic obstructive pulmonary disease.

Thiamine deficiency and unexplained encephalopathy in hemodialysis and peritoneal dialysis patients.

Patients with end-stage renal disease undergoing regular dialysis are prone to encephalopathy, but the cause is often unclear. Dialysis patients are at risk for thiamine deficiency, which may mimic many uremic complications, including encephalopathy. To determine whether unexplained encephalopathy in regular dialysis patients is associated with thiamine deficiency, we conducted a prospective study that enrolled 30 consecutive dialysis patients with altered mental status admitted to a referred hospital during a 1-year period. A complete history, physical and neurological examinations, laboratory investigations, and computed tomographic scans or magnetic resonance imaging of the brain were obtained for each subject. In 10 of the 30 patients, diagnoses remained obscure after the initial workup. Manifestations included confusion, chorea, acute visual loss, rapidly progressive dementia, myoclonus, convulsions, and coma. Intravenous thiamine was administered to these 10 patients. All 10 patients had thiamine deficiency confirmed by a marked response to thiamine supplementation and/or a low serum thiamine concentration (35.3 +/- 6.0 nmol/L; normal, >50 nmol/L). Nine patients recovered, but one patient failed to respond because of delayed treatment. We conclude that in regular dialysis patients, unexplained encephalopathy can be mainly attributed to thiamine deficiency. This condition is fatal if unrecognized and can be successfully treated with prompt thiamine replacement.

Surgical treatment for concomitant fractures of the femoral neck and diaphysis: a treatment protocol.

Concomitant ipsilateral femoral shaft and neck fractures are difficult to treat. The standard protocol in our hospital is plates for diaphyseal fractures and lag screws or dynamic hip screws (DHS) fixations for the femoral neck fractures. We treated 21 patients with these complex fractures between 1988 and 1998 with this protocol. All patients were injured from high-energy trauma. There were 15 males and 6 females with an average age of 44 years. The average follow-up period is 50 months. All except one patient united well. During the follow-up period, neither non-union of the femoral neck fracture nor osteonecrosis of the femoral head was noted. There was also no malunion. There were twenty good results and one poor functional result. We conclude that plate on the shaft and sliding hip screws or separate screws in the hip are a reliable method for concomitant ipsilateral femoral neck and shaft fractures.

Chorea induced by thiamine deficiency in hemodialysis patients.

Thiamine deficiency is mainly encountered in alcoholics or food faddists, but it may complicate chronic dialysis because of low intake and accelerated loss of thiamine in dialysis patients. We report here 2 hemodialysis (HD) patients who developed chorea induced by thiamine deficiency. We propose that thiamine deficiency, with a consequent dysfunction of the basal ganglia, may induce chorea in HD patients.

Ipsilateral fractures of the femoral neck and shaft.

Ipsilateral femoral shaft and neck fractures are difficult to treat. From 1989 to 1998, we treated 18 patients with these complex fractures. There were 14 male and 4 female with an average age of 40 years. Most resulted from high-energy trauma. The average follow-up period is 41 months. All but one of the fractures united well. The mean time to union is 5.2+/-2.3 months in the diaphysis and 4.16+/-2 months in the neck. No cases of the femoral neck fracture or osteonecrosis of the femoral head were observed during the follow-up period. Fourteen cases were treated with a standard protocol of plates for diaphyseal fractures and lag screws or dynamic hip screws (DHS) fixations for the femoral neck fractures. There were 13 good and 1 fair functional results. Two neglected neck fractures were treated with interlocking nailing for diaphyseal fracture with fair results. We conclude that a plate on the shaft and sliding hip screws or separate screws in the hip is a reliable method for ipsilateral femoral neck and shaft fractures.

The role of cell density in the survival of cultured cerebellar granule neurons.

The dependence for survival of cerebellar granule neurons on the cell density was examined both experimentally and theoretically. The results of batch experiments revealed that the cell survival index (CSI) was inappreciable, if cell density was below a critical level. If cell density exceeded this critical value, CSI increased with the increase in cell density. In addition, CSI was significantly increased by using a conditioned medium from the dense cultures. This suggests that not only cell density promotes survival of neurons, but also an increased concentration of growth factors produced by neurons has a direct effect on the survival of the neurons. A quantitative model describing the distribution of the growth factor at different cell densities was proposed to investigate the role of cell density in the survival of the neurons. We showed the existence of a critical level for cell density, and good agreement in the improvement of CSI was found between the theoretical prediction and the experimental result. Finally, the average concentration of growth factor necessary for cell survival based on our model was in a reasonable range compared to the practice of the addition of neurotrophic factors to the medium of cultured cerebellar granule neurons.

Core decompression for osteonecrosis of the femoral head at pre-collapse stage.

Twenty-five patients (27 hips) were retrospectively studied for core decompression in the treatment of osteonecrosis of the femoral heads at pre-collapse stage, Ficat and Alert stages I and II, from Apr. 1984 to Jun. 1998 with follow-up period at least 1 yr (mean 28 months). Eleven hips (10 patients) were considered to have failed due to progressive collapsed more than 2 mm, severe pain or reoperation. We further analyzed the results with regard to the stages, the size of the necrotic area according to the Ohzono classification, the lateral head index (LHI) and the Kerboul combined necrotic angle. The survival rate according to the Ohzono classification was type 1B: 100%, 1C: 44%, 2: 25%, and 3B: 0%. Hips with Kerboul angle less than 250 degrees revealed satisfactory results in all except one hip. All hips with Kerboul angle more than 250 degrees collapsed. Fourteen of the 15 hips (93%) with lateral head index more than 20% did not collapse and all hips except one (7/8) with LHI less than 12% collapsed. We conclude core decompression yields satisfactory results in osteonecrotic femoral heads at pre-collapse stage and with small necrotic area or good lateral buttress.

The surgical treatment for degenerative disease of the ankle.

Although a variety of surgical techniques are available for the surgical treatment of early degenerative disease of the ankle, arthrodesis remains the preferred treatment for severe cases. We studied 126 ankles with an average follow up of 39 months of whom 25 with early disease underwent debridement and cheilectomy, 18 with intermediate disease underwent lower tibial osteotomy and 83 with severe disease underwent either arthrodesis (78) or total ankle replacement (5). In 96% of cases there was a satisfactory functional outcome.

Active site specificity of plasmepsin II.

Members of the aspartic proteinase family of enzymes have very similar three-dimensional structures and catalytic mechanisms. Each, however, has unique substrate specificity. These distinctions arise from variations in amino acid residues that line the active site subsites and interact with the side chains of the amino acids of the peptides that bind to the active site. To understand the unique binding preferences of plasmepsin II, an enzyme of the aspartic proteinase class from the malaria parasite, Plasmodium falciparum, chromogenic octapeptides having systematic substitutions at various positions in the sequence were analyzed. This enabled the design of new, improved substrates for this enzyme (Lys-Pro-Ile-Leu-Phe*Nph-Ala/Glu-Leu-Lys, where * indicates the cleavage point). Additionally, the crystal structure of plasmepsin II was analyzed to explain the binding characteristics. Specific amino acids (Met13, Ser77, and Ile287) that were suspected of contributing to active site binding and specificity were chosen for site-directed mutagenesis experiments. The Met13Glu and Ile287Glu single mutants and the Met13Glu/Ile287Glu double mutant gain the ability to cleave substrates containing Lys residues.

Ankle arthrodesis: internal non-compression arthrodesis versus internal compression arthrodesis.

Ankle arthrodesis is still considered to be the standard treatment for most disabling types of ankle arthritis, but fusion methods are varied. We report our experience of ankle arthrodesis and compare a group of 34 cases treated by Blair's non-compression arthrodesis to another group of 32 cases treated by internal compression arthrodesis using two crossed screws. The same surgeon performed all the operations. The Blair's non-compression arthrodesis group included 21 males and 13 females with an average age of 42 y/o (range 18-70 y/o) and an average follow up period of 38.6 months (range 26-62 months). The union rate was 91.2% and the average union time was 5.6 months (range 2-10 months). There were three cases of non-union. The cross-screw compression arthrodesis group included 20 males and 12 females with an average age of 45 y/o (range 20-86 y/o) and an average follow up period of 38.3 months (range 15-81 months). The union rate was 96.9% and the average union time was 2.7 months (range 1.5-4.4 months). There was one case of non-union. We conclude that our cross-screws compression arthrodesis with its shorter fusion time was found to be superior to the Blair's non-compression arthrodesis.