Development of Innovative Contra-angle Handpiece Device with Piston Movement for Root Canal Preparation.

INTRODUCTION: The purpose of this study was to assess the optimal amplitude and weight of the newly developed contra-angle handpiece. The handpiece uses piston movement without using an endodontic motor and enables a safe, quick, and reliable canal preparation. METHODS: A prototype handpiece was designed. Instrumentation was performed on root canal resin blocks by 20 operators in 3 groups: the prototype handpiece with an H file (a stainless steel #25 manual H file, the piston group), a manually standardized technique with a K file (stainless steel #15-25 K files, the manual group), and a nickel-titanium (NiTi) reciprocating file with an endodontic motor (Reciproc Blue R25 [VDW, Munich, Germany], the NiTi group). Transportation of the canal center line and the time required for preparation were measured and statistically analyzed. RESULTS: The optimal condition was an amplitude of 1.35 mm and a weight of 61.0 g. Transportation of the canal center was observed in all groups. A statistically significant difference was found at 2.0-3.0 mm from the apical foramen between the piston or NiTi group and the manual group, but no significant difference was found between the piston and NiTi groups. The least transportation was found in the NiTi and piston groups. The handpiece with a #25 H file demonstrated a good centering ability, similar to the NiTi file, which enabled speedy preparation. The time required for preparation between the piston or NiTi group and the manual group was statistically different. No significant difference was observed between the piston and NiTi groups (P < .05). CONCLUSIONS: We concluded that the newly designed handpiece achieved efficient canal preparation and negotiation. The handpiece could avoid endodontic accidents, including ledge formation, instrument separation, and perforation.

Characterization of the denitrifying bacterial community in a full-scale rockwool biofilter for compost waste-gas treatment.

The potential denitrification activity and the composition of the denitrifying bacterial community in a full-scale rockwool biofilter used for treating livestock manure composting emissions were analyzed. Packing material sampled from the rockwool biofilter was anoxically batch-incubated with 15N-labeled nitrate in the presence of different electron donors (compost extract, ammonium, hydrogen sulfide, propionate, and acetate), and responses were compared with those of activated sludge from a livestock wastewater treatment facility. Overnight batch-incubation showed that potential denitrification activity for the rockwool samples was higher with added compost extract than with other potential electron donors. The number of 16S rRNA and nosZ genes in the rockwool samples were in the range of 1.64-3.27 × 109 and 0.28-2.27 × 108 copies/g dry, respectively. Denaturing gradient gel electrophoresis analysis targeting nirK, nirS, and nosZ genes indicated that the distribution of nir genes was spread in a vertical direction and the distribution of nosZ genes was spread horizontally within the biofilter. The corresponding denitrifying enzymes were mainly related to those from Phyllobacteriaceae, Bradyrhizobiaceae, and Alcaligenaceae bacteria and to environmental clones retrieved from agricultural soil, activated sludge, freshwater environments, and guts of earthworms or other invertebrates. A nosZ gene fragment having 99% nucleotide sequence identity with that of Oligotropha carboxidovorans was also detected. Some nirK fragments were related to NirK from micro-aerobic environments. Thus, denitrification in this full-scale rockwool biofilter might be achieved by a consortium of denitrifying bacteria adapted to the intensely aerated ecosystem and utilizing mainly organic matter supplied by the livestock manure composting waste-gas stream.

Study of pruritus in chronic hepatitis C patients.

AIM: To investigate the occurrence and severity of pruritus in chronic hepatitis C patients treated with or without interferon (IFN) therapy. METHODS: A total of 89 patients with chronic hepatitis C and 55 control (non-hepatitis) patients were asked to rate their experience of diurnal and nocturnal pruritus in the preceding week using a visual analogue scale (VAS) and a five-point scale, respectively. Blood samples were taken and serum thymus and activation-regulated chemokine (TARC) levels were measured by enzyme-linked immunosorbent assay. RESULTS: A significantly greater proportion of chronic hepatitis C patients experienced nocturnal pruritus compared with control (58.4% vs 5.5%, P < 0.0001). Chronic hepatitis C patients also had more severe pruritus compared with control patients, indicated by the higher mean VAS scores in both the IFN-treated and non-IFN-treated groups. In particular, patients who received combined peginterferon alfa-2b and ribavirin had significantly higher mean VAS scores than those receiving peginterferon alfa-2a or no IFN treatment. Serum TARC levels did not correlate with pruritus scores, and no significant differences in TARC levels were observed between the IFN-treated and non-IFN-treated groups. CONCLUSION: Patients with chronic hepatitis C experience pruritus more than those without. Serum TARC levels do not correlate with pruritus severity in chronic hepatitis C patients.

A proposed core curriculum for dental English education in Japan.

BACKGROUND: Globalization of the professions has become a necessity among schools and universities across the world. It has affected the medical and dental professions in terms of curriculum design and student and patient needs. In Japan, where medicine and dentistry are taught mainly in the Japanese language, profession-based courses in English, known as Medical English and Dental English, have been integrated into the existing curriculum among its 83 medical and 29 dental schools. Unfortunately, there is neither a core curriculum nor a model syllabus for these courses. METHODS: This report is based on a survey, two discussion forums, a workshop, and finally, the drafting of a proposed core curriculum for dental English approved by consensus of the participants from each university. RESULTS: The core curriculum covers the theoretical aspects, including dental English terms and oral pathologies; and practical aspects, including blended learning and dentist-patient communication. It is divided into modules and is recommended to be offered for at least two semesters. CONCLUSIONS: The core curriculum is expected to guide curriculum developers in schools where dental English courses are yet to be offered or are still in their early development. It may also serve as a model curriculum to medical and dental schools in countries in Asia, Europe, Africa, and Central and South America, where English is not the medium of instruction.

Effect of pH on phosphorus, copper, and zinc elution from swine wastewater activated sludge.

With the goal of reducing the amounts of phosphorus (P), copper (Cu), and zinc (Zn) discharged from swine wastewater activated sludge treatment facilities, we studied the elution of these elements from activated sludge at various pH values. Sludge samples with neutral pH collected from three farms were incubated at pH values ranging from 3 to 10. The soluble concentrations of these elements changed dramatically with pH and were highest at pH 3. We assumed that P present in the sludge under neutral and alkaline conditions was in insoluble form bound up with magnesium (Mg) and calcium (Ca), because Ca and Mg also eluted from the sludge at low pH. To clarify forms of Zn and Cu in the sludge, we performed a sequential extraction analysis. Zinc in adsorbed, organically bound, and sulfide fractions made up a large proportion of the total Zn. Copper in organically bound, carbonate, and sulfide fractions made up a large proportion of the total Cu. The soluble P concentrations were lowest at pH 9 or 10 (11-36 mg/L), the soluble Zn concentrations were lowest at pH 8 or 9 (0.07-0.15 mg/L), and the soluble Cu concentrations were lowest at pH 6-9 (0.2 mg/L, the detection limit).

Effect of electron donors on anammox coupling with nitrate reduction for removing nitrogen from nitrate and ammonium.

Anammox coupling with nitrate reduction under various electron donors was studied using sludge acclimatized to have anammox and denitrification activities. Due to a deficiency in electron donors for NO(3)(-) reduction, anammox activity in an inorganic medium containing NO(3)(-) and NH(4)(+) was lower than that in NO(2)(-) and NH(4)(+). Anammox could use NO(2)(-) competitively against denitrifiers under a very limited NO(2)(-) concentration, and additions of swine wastewater or acetate stimulated anammox activity in an inorganic medium containing NO(3)(-) and NH(4)(+) with no inhibition effects. However, a high concentration of swine wastewater caused an exponential increase in denitrification activity. The addition of hydrogen and iron stimulated anammox activity in an inorganic medium containing NO(3)(-) and NH(4)(+), but iron showed an inhibitory effect on anammox in a medium containing NO(2)(-) and NH(4)(+). Hydrogen was shown to be advantageous since it did not increase denitrification even when its addition was increased.

Estimation of Zn and Cu unit output loads from animal husbandry facilities.

Zinc (Zn) and copper (Cu) are toxic to aquatic organisms at very low concentrations that do not affect humans. We measured the daily output of Zn and Cu in wastewater from livestock farms to aquatic environments because waste from animal husbandry operations contains high levels of Zn and Cu. At most pig farms in Japan, a mixture of urine, some faeces, and service water is treated in onsite wastewater treatment facilities and discharged into a water body. Some dairy farms also have wastewater treatment facilities. We surveyed 21 pig farms and six dairy farms. The unit (i.e., per head) output load from piggery wastewater treatment facilities ranged from 0.13 to 17.8 mg/head/d for Zn and from 0.15 to 9.4 mg/head/d for Cu. Over 70% of pig farms had unit output loads of Zn and Cu below 6 and 2 mg/head/d, respectively. For dairy farms, the unit output load from wastewater treatment facilities was estimated at 1.8-3.6 mg/head/d for Zn and 0.6 mg/head/d for Cu. The unit output load for Zn from piggery wastewater treatment facilities was similar to that from treatment facilities for human waste. However, pig farms generally raise several thousand to tens of thousands of pigs; pig farms are therefore presumed to be a significant point source of Zn in rural areas.

Evidence of exponential growth of an anammox population in an anaerobic batch culture.

Twenty-five replicates of growth medium for anaerobic ammonium oxidation (anammox) containing (15)N-labeled ammonium and non-labeled nitrite were inoculated into an anammox enrichment culture at low density, and anaerobically incubated batchwise. In the headspace, (29)N(2) partial pressure linearly increased via anammox in 25 vials, confirming that anammox populations were viable in all subcultures. On prolonged incubation, exponential increases in (29)N(2) were not observed in all but 13 subcultures, suggesting that the anammox population may not proliferate unless all conditions for growth are satisfied. The estimated first-order rate coefficients in those 13 subcultures varied from 0.0029 to 0.0048 h(-1).

Effects of struvite formation and nitratation promotion on nitrogenous emissions such as NH3, N2O and NO during swine manure composting.

To reduce nitrogenous emissions from composting, two different countermeasures were applied simultaneously in swine manure composting. One was forming struvite by adding Mg and P at the start of composting, and the other was to promote nitratation (nitrite being oxidized nitrate) by adding nitrite-oxidizing bacteria after the thermophilic phase of composting. In the laboratory- and mid-scale composting experiments, 25-43% of NH3, 52-80% of N2O and 96-99% of NO emissions were reduced. From the nitrogen balance, it was revealed that the struvite formation reduced not only NH3, but also other nitrogenous emissions except N2O. The amount of total nitrogen losses was reduced by 60% by the two combined countermeasures, against 51% by the struvite formation alone. However, the nitratation promotion dissolved struvite crystals due to the pH decline, diminishing the effect of struvite as a slow-release fertilizer.

Correlation between Changes in Leg Blood Flow and Ankle-Brachial Pressure Index: A Study Using Laser Doppler Flowmeter -The 1st Report-.

OBJECTIVE: The objective of this study was to use non-invasive laser Doppler flowmeter to measure changes in blood flow in peripheral vessels in the legs before and after stress induced by leg elevation stress test and investigate correlations with the ankle-brachial pressure index (ABI). METHODS: Subjects included 28 patients over 20 years of age (mean, 73 years) who reported chiefly of leg symptoms such as intermittent claudication, numbness, chills, or cramps had been examined at the study institution, and agreed to participate in the study. The ABI of both legs was measured, and patients were divided into two groups: low ABI (ABI ≤0.9) and normal ABI (ABI ≥0.9). Blood flow in the big toe was measured using a box-type laser Doppler flowmeter before, during, and after leg-elevation stress. Amplitude of the recorded waveform and changes in blood flow were compared. RESULTS: Average ABI was 1.09 ± 0.10 in the normal ABI group (33 legs) and 0.68 ± 0.17 in the low ABI group (21 legs). Amplitude before and during stress was significantly smaller in the low ABI group than in the normal ABI group (p <0.01), and there was a significant correlation with ABI before and during stresses (r = 0.4606, r = 0.5048, respectively; p <0.05). Change in blood flow during stress was significantly lower in the low ABI group than in the normal ABI group (p <0.05). There was a significant correlation between change in blood flow during stress and ABI in both groups (r = 0.5073; p <0.05). There was also a significant correlation between change in blood flow and change in amplitude in both groups (r = 0.5477; p <0.05). CONCLUSION: RESULTS of this study show, that comparing amplitude and change in blood flow before and after leg extension and elevation stress, there was a correlation between change in blood flow and amplitude, and ABI during stress. A box-type laser Doppler flowmeter may provide a means of screening for peripheral arterial disease.

Effects of late evening snack on diurnal plasma glucose profile in patients with chronic viral liver disease.

AIM: Glycemic control is important to improve the prognosis in cirrhotic patients with complications from diabetes. A late evening snack (LES) has been recommended for cirrhotic patients. We investigated the effects of LES on diurnal plasma glucose levels. METHODS: Subjects comprised 47 patients with chronic viral liver disease (chronic hepatitis, n = 11; cirrhosis, n = 36) treated in the Department of Gastroenterology & Hepatology, Dokkyo Medical University Koshigaya Hospital. Diurnal variations in plasma glucose were first investigated with three meals/day, in accordance with the European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines. Starting the next day, patients were given four meals including a LES, without changing meal content. Diurnal variations in plasma glucose were examined on day 7, and urine C-peptide immunoreactivity (CPR), and homeostasis model assessment insulin resistance (HOMA-IR) were investigated. RESULTS: With a LES, plasma glucose levels in patients with chronic hepatitis were significantly lower 2 hours before and 2 hours after dinner. In cirrhotic patients, significant decreases in plasma glucose levels were seen 2 hours after breakfast, before lunch, and before dinner. Significant decreases were noted in average plasma glucose levels and highest plasma glucose levels with four meals including a LES in patients with liver cirrhosis. This decrease was greater when maximum plasma glucose levels were higher on the three-meal regimen. CONCLUSIONS: Improvements in plasma glucose levels were seen with four meals per day, including a LES, in viral chronic liver disease, particularly cirrhosis.

Iteratively-reweighted local model fitting method for adaptive and accurate single-shot surface profiling.

The local model fitting (LMF) method is one of the useful single-shot surface profiling algorithms. The measurement principle of the LMF method relies on the assumption that the target surface is locally flat. Based on this assumption, the height of the surface at each pixel is estimated from pixel values in its vicinity. Therefore, we can estimate flat areas of the target surface precisely, whereas the measurement accuracy could be degraded in areas where the assumption is violated, because of a curved surface or sharp steps. In this paper, we propose to overcome this problem by weighting the contribution of the pixels according to the degree of satisfaction of the locally flat assumption. However, since we have no information on the surface profile beforehand, we iteratively estimate it and use this estimation result to determine the weights. This algorithm is named the iteratively-reweighted LMF (IRLMF) method. Experimental results show that the proposed algorithm works excellently.

Distribution of phosphorus, copper and zinc in activated sludge treatment process of swine wastewater.

Changes in swine wastewater chemical features during an activated sludge treatment process were surveyed on 11 farms, and analyzed with non-biodegradable elements, i.e., phosphorus (P), copper (Cu), and zinc (Zn). In piggery wastewater, they were linearly correlated with suspended solid (SS) concentrations and the major portion was in solid fractions. After the pretreatment step, they were removed, with 80% for total P, 85% for total Cu, and 84% for total Zn. After the activated sludge process, total P, Cu, and Zn were then removed at 83%, 96%, and 95%, respectively. Removing SS thoroughly at each step was shown to be the most important factor in preventing outflow of these elements, since there are linear correlations or a positive relationship between the removal of SS concentrations and their removal in solid form. Most of the P, Cu, and Zn in activated sludge effluent was in soluble form, and the concentrations of Cu and Zn in the effluent were low enough, while further P removal might be required.

Characteristics of the microbial community associated with ammonia oxidation in a full-scale rockwool biofilter treating malodors from livestock manure composting.

The relationship between the activity and community structure of microbes associated with the oxidation of ammonia in a full-scale rockwool biofilter was examined by kinetic, denaturing gradient gel electrophoresis (DGGE), and sequence analyses. The packing materials were sampled from two different depths at 3 sites. Estimated K(m) values were similar among depths at same sampling sites, while V(max) differed in the mid-point sample. The lower depth of this site had the highest V(max). A correspondence analysis showed the DGGE profile of ammonia-oxidizing bacterial amoA of the lower depth of the mid-point sample to be distinguishable from the others. Banding patterns at other sites were similar among depths. Banding patterns of ammonia-oxidizing archaeal amoA of the mid-point sample were also similar among depths. The results suggested an association between the ammonia-oxidizing bacterial community's composition and ammonium oxidation kinetics in samples. Sequence analysis indicated that the ammonia-oxidizing bacterial community mainly belonged to the Nitrosomonas europaea lineage and Nitrosospira cluster 3. The ammonia-oxidizing archaeal amoA-like sequences were related to those belonging to soil and sediment groups, including one with 84% nucleotide similarity with Nitrosopumilus maritimus.

Rate determination and distribution of anammox activity in activated sludge treating swine wastewater.

This paper presents a quantitative investigation and analysis of anammox activity in sludge taken from biological swine wastewater treatment plants. An incubation experiment using a (15)N tracer technique showed anammox activity in sludge taken from 6 out of 13 plants with the rate ranging from 0.0036 micromol-N(2)/g-VSS/h to 3.1 micromol-N(2)/g-VSS/h, and in a biofilm with the highest activity at 25.8 micromol-N(2)/g-VSS/h. It is notable that 9 out of 11 sludges in which the pH was maintained between 6.6 and 8.1 retained anammox activity, while those with either a lower or higher pH did not. Moreover, anammox-positive sludge had a significantly higher concentration of NO(2)(-)-N plus NO(3)(-)-N than did anammox-negative sludge. A significant difference was not observed between anammox-positive and -negative sludge regarding BOD/NH(4)(+)-N in the influent, DO concentration in aeration tanks, and the concentrations of NH(4)(+)-N, free nitric acid, and free ammonia.

Nitrogen removal by co-occurring methane oxidation, denitrification, aerobic ammonium oxidation, and anammox.

The pathway for removing NO(3)(-) and NH(4)(+) from wastewater in the presence of both CH(4) and O(2) was clarified by studying microbial activity and community. Batch incubation tests were performed to characterize the microbial activity of the sludge, which was acclimatized in a bioreactor in which O(2) and CH(4) were supplied to treat wastewater containing NO(3)(-) and NH(4)(+) . The tests showed that the sludge removed significant amounts of NO(3)(-) and NH(4)(+) in the presence of CH(4) and O(2), and the presence of the activity of methane oxidation, denitrification, nitrification, and anammox in the sludge. It was estimated that the total inorganic nitrogen removal was attributed to denitrification associated with methane oxidation as 53.4%, microbial assimilation as 37.9%, and anammox as 8.7%. Nitrification also contributed to NH(4)(+) decrease as 34.5% and anammox as 6.4%. Anammox activity was unambiguously demonstrated by (29)N(2) production in anaerobic batch incubation with (15)N-labeled inorganic nitrogen compounds. The presence of methane-oxidizing bacteria and candidate denitrifiers in the sludge was shown by denaturing gradient gel electrophoresis of 16S rRNA gene fragments. Clone library analysis of the PCR-amplified 16S rRNA gene fragment using specific primers for aerobic ammonium oxidizer and anammox revealed the presence of these bacteria. The results reveal that complex nitrogen-removal processes occur in the presence of CH(4) and O(2) by methanotroph, denitrifier, aerobic ammonium oxidizer, and anammox.

Interpolated local model fitting method for accurate and fast single-shot surface profiling.

The local model fitting (LMF) method is a useful single-shot surface profiling algorithm based on spatial carrier frequency fringe patterns. The measurement principle of the LMF method relies on the assumption that the target surface is locally flat. In this paper, we first analyze the measurement error of the LMF method caused by violation of the locally flat assumption. More specifically, we theoretically prove that the measurement error is zero at fringe intensity extrema in an interference pattern even when the locally flat assumption is violated. Based on this theoretical finding, we propose a new surface profiling method called the interpolated LMF (iLMF) algorithm, which is more accurate and computationally efficient than the original LMF method. The practical usefulness of the iLMF method is shown through experiments.

Evaluation of full-scale biofilter with rockwool mixture treating ammonia gas from livestock manure composting.

NH3 removal by a full-scale biofilter with rockwool packing materials was studied by measuring the gases and potential nitrification and denitrification activities of those materials in order to improve the biofiltration technology used in livestock farms. The rockwool biofilter was a durable and effective system for removing NH3, which was varied with the turning of manure composts. Furthermore, NH3 could be treated in the absence of an extra increase in two greenhouse gases, N2O and CH4. Potential nitrification and denitrification activities of the packing materials were estimated to be 8.2-12.2 mg N, and 1.42-4.69 mg N/100 g dry samples per day, respectively. The results suggested that potential nitrification and denitrification activities would increase within the biofilter where substrates, NH3 or NO3(-), have accumulated as a result of its operation. However, since percolate water contained high concentrations of NH4(+) and NO3(-), further improvement is required by reducing nitrogenous compounds within both the biofilter and percolate water.

[Three cases with liver metastasis from gastric or colon cancer successfully treated with S-1 combined with CPT- 11].

We report three cases with liver metastasis from gastric or colon cancer successfully treated with S-1 with CPT-11. Case 1: A total gastrectomy was performed for a gastric cancer located in the lower to upper body of the stomach (T3 (SE), N2, H0, P0, por 2, stage III B). Abdominal computed-tomography (CT) revealed a solitary liver metastasis in the S8 subsegment of the liver. We treated the patient with S-1 combined with CPT-11. Abdominal CT revealed a complete response (CR) after 5 courses. Case 2: Sigmoidectomy and partial resection of small intestine and abdominal wall were performed for sigmoid colon cancer. The intraoperative findings revealed liver metastases in left lobe of the liver (Si, N1, H1, P0, M0, tub 1, stage IV). After surgery, the patient was treated with S-1 combined with CPT-11. Abdominal CT demonstrated CR after 5 courses. Case 3: Laparoscopic right hemicolectomy was performed for ascending colon cancer (SE, N1, H0, P0, M0, tub 1, stage III a). Abdominal CT showed a solitary liver metastasis in the S6 subsegment of the liver 3 months after surgery. We treated the patient with S-1 combined with CPT-11. Abdominal CT revealed CR after 3 courses. The three cases are alive without any signs of recurrence.