Examination of the traction effect in an artificial muscle-type dynamic traction orthosis using computed tomography

BACKGROUND

Dart-throwing motion from radial dorsiflexion to palmar flexion has recently attracted attention as a functional movement direction of the wrist joint. We developed a novel artificial muscle-type dynamic traction orthosis (DTSaM) that includes these movements. This prospective crossover controlled study aimed to compare the traction effects in the presence and absence of DTSaM using computed tomography.

METHODS

Healthy participants with no history of finger disease (6 men: 6 fingers, 4 women: 4 fingers; average age [range]: 29.4 [34-24] years) were examined. The distance and area of the joint space between the radiolunate (RL) and capitolunate (CL) joints were evaluated using 2 types of computed tomography: automatic movement and DTSaM.

RESULTS

Participants with DTSaM showed more dilated joint space distance on the dorsal and central sides (p < 0.05) and larger joint space areas on the dorsal side (p < 0.05) of the RL and CL joints than those without orthosis. Significant differences in the magnitude of change in each joint were observed between the RL and CL joints regarding the joint space distance on the dorsal (p = 0.021) and central (p = 0.038) sides and the joint space area on the dorsal side (p = 0.044).

CONCLUSIONS

The movement of the CL joint is important in the dorsiflexion direction. Our results suggest that the dilated CL joint allows dorsiflexion and that combined traction and dart-throwing motion exercises may be possible for wrist joint contracture.

Occupational Fall Risk Assessment Tool for older workers

BACKGROUND

No easy-to-use fall risk assessment tools have been devised to assess occupational fall risk in older workers.

AIMS

To develop an Occupational Fall Risk Assessment Tool (OFRAT) and report its predictive validity and reliability in older workers.

METHODS

The baseline fall risk assessment was completed by 1113 participants aged ≥60 years who worked ≥4 days/month in Saitama, Japan. Participants were followed up for falls during occupational activities for 1 year, and 30 participants were assessed twice for test-retest reliability. The following assessment measures were summed to form the OFRAT risk score: older age, male sex, history of falls, physical work participation, diabetes, use of medications increasing fall risk, reduced vision, poor hearing, executive dysfunction and slow stepping. The scores were then classified into four grades (0-2 points: very low, 3 points: low, 4 points: moderate and ≥5 points: high).

RESULTS

During follow-up, 112 participants fell 214 times during work. The negative binomial regression model showed that participants with higher grades had a higher incidence rate ratio [95% confidence interval] for falls than those with very low grades (low: 1.64 [1.08-2.47], moderate: 4.23 [2.82-6.34] and high: 6.12 [3.83-9.76]). The intraclass correlation coefficient for risk score was 0.86 [0.72-0.93], and the weighted kappa coefficient for grade assessment was 0.74 [0.52-0.95].

CONCLUSIONS

The OFRAT is a valid and reliable tool for estimating the occupational fall risk in older workers. It may assist occupational physicians implement strategies to prevent falls in this group.

AB0439 COMPARATIVE EFFECTIVENESS OF RAPID AND CONVENTIONAL GLUCOCORTICOID TAPERING REGIMENS IN TREATING PATIENTS WITH PROLIFERATIVE LUPUS NEPHRITIS IN THE REAL WORLD SETTING

Background

Rapid glucocorticoid (GC) tapering is recommended for lupus nephritis (LN) by 2019 EULAR/ERA-EDTA recommendations [1]. However, slower conventional GC tapering regimen is still common in the real world setting, and it is controversial whether a rapid GC tapering regimen is as effective as the conventional regimen.

Objectives

We aimed to compare the renal outcomes between rapid and slower GC tapering regimens in patients with LN.

Methods

We retrospectively surveyed the medical records of 27 patients with proliferative LN (class Ⅲ or Ⅳ) at Kobe City Medical Center General Hospital. These patients were divided into two groups (rapid GC tapering group and conventional GC tapering group) according to GC dosage at month 6. Logistic regression analyses were performed to examine the association of GC tapering regimens with achievement of primary efficacy renal response (PERR) and complete renal response (CRR) which were defined by Furie et al. [2] at month 24.

Results

Twenty-seven patients (19 women and 8 men) with class Ⅲ or Ⅳ LN were included. The mean age was 43 years. The mean eGFR and urine protein-to-creatinine ratio at baseline were 66.7 mL/min/1.73m2 and 3.125 g/gCr, respectively. Concomitant class Ⅴ LN was present in 26.0%. The rapid GC tapering group (PSL≦10 mg/day at month 6) and the conventional GC tapering group (PSL>10 mg/day at month 6) were 11 and 16 patients, respectively. Baseline characteristics were balanced between the two groups except for use of cyclophosphamide or mycophenolate mofetil. Mean urine protein-to-creatinine ratio at month 24 were 0.46 g/gCr in the rapid GC tapering regimen group and 1.08 g/gCr in the conventional GC tapering regimen group (p=0.790). Achievements of PERR and CRR at month 24 were 54.0% and 43.8% in the rapid GC tapering group and 54.5% and 25.0% in the conventional GC tapering group, respectively. After adjustment of cyclophosphamide or mycophenolate mofetil usage and urine protein-to-creatinine ratio at baseline, adjusted odds ratio was 1.52 (95% confidence interval [0.126 to 18.29], p=0.743) and 2.99 (95% confidence interval [0.34 to 28.52], p=0.341), respectively.

Conclusion

Our results suggest rapid GC tapering regimen is as effective as conventional slower tapering regimen for patients with proliferative LN.

References

[1]Fanouriakis A, Kostopoulou M, Cheema K, et al. 2019 Update of the Joint European League Against Rheumatism and European Renal Association-European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of lupus nephritis. Ann Rheum Dis 2020;79:713–723.

[2]Furie R, Rovin BH, Houssiau F, et al. Two-Year, Randomized, Controlled Trial of Belimumab in Lupus Nephritis. N Engl J Med 2020;383:1117–1128.

Table 1.

Baseline patients characteristics.

Rapid GC tapering group(n=11)Conventional GC tapering group(n=16)P valueAge – years41.7 ± 14.743.9 ± 16.20.863Female – no. (%)9 (81.8)10 (62.5)0.405Class Ⅲ LN – no. (%)6 (54.5)7 (43.8)0.704Class Ⅳ LN – no. (%)6 (45.5)9 (56.3)0.704Concomitant Class Ⅴ LN – no. (%)4 (36.4)3 (18.8)0.391Induction therapy (use of CY or MMF) – no. (%)10 (90.9)8 (50.0)0.042Serum creatinine – mg/dL1.15 ± 0.721.14 ± 0.800.882eGFR – mL/min/1.73m265.2 ± 39.067.8 ± 34.50.835UPCR – g/gCr3.29 ± 2.963.01 ± 3.250.604C3 – mg/dL41.1 ± 20.145.0 ± 21.50.639C4 – mg/dL6.8 ± 4.710.1 ± 8.00.346

GC, glucocorticoid; LN, lupus nephritis; UPCR, urine protein-to-creatinine ratio; CY, cyclophosphamide; MMF, mycophenolate mofetil

Disclosure of Interests

None declared

The cumulative incidence of and risk factors for morphometric severe vertebral fractures in Japanese men and women: the ROAD study third and fourth surveys

This population-based cohort study with a 3-year follow-up revealed that the annual incidence rates of vertebral fracture (VF) and severe VF (sVF) were 5.9%/year and 1.7%/year, respectively. The presence of mild VF at the baseline was a significant risk factor for incident sVF in participants without prevalent sVF.

INTRODUCTION

This study aimed to estimate the incidence of morphometric vertebral fracture (VF) and severe VF (sVF) in men and women and clarify whether the presence of a mild VF (mVF) increases the risk of incident sVF.

METHODS

Data from the population-based cohort study, entitled the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) study, were analyzed. In total, 1190 participants aged ≥ 40 years (mean age, 65.0 ± 11.2) years completed whole-spine lateral radiography both at the third (2012-2013, baseline) and fourth surveys performed 3 years later (2015-2016, follow-up). VF was defined using Genant's semi-quantitative (SQ) method: VF as SQ ≥ 1, mVF as SQ = 1, and sVF as SQ ≥ 2. Cumulative incidence of VF and sVF was estimated. Multivariate logistic regression analyses were performed to evaluate risk factors for incident sVF.

RESULTS

The baseline prevalence of mVF and sVF were 16.8% and 6.0%, respectively. The annual incidence rates of VF and sVF were 5.9%/year and 1.7%/year, respectively. The annual incidence rates of sVF in participants without prevalent VF, with prevalent mVF, and with prevalent sVF were 0.6%/year, 3.8%/year, and 11.7%/year (p < 0.001), respectively. Multivariate logistic regression analyses in participants without prevalent sVF showed that the adjusted odds ratios for incident sVF were 4.12 [95% confident interval 1.85-9.16] and 4.53 [1.49-13.77] if the number of prevalent mVF at the baseline was 1 and ≥ 2, respectively.

CONCLUSIONS

The annual incidence rates of VF and sVF were 5.9%/year and 1.7%/year, respectively. The presence of prevalent mVF was an independent risk factor for incident sVF.

Analysis of a New Artificial Muscle Type Dynamic Orthosis for Wrist Joint Disease Using a Three-dimensional Motion Analyzer

Objectives:

Recently, the dart-throwing motion (DTM) has attracted attention as a functional direction of wrist joint motion. Consequently, we devised a new artificial muscle-type dynamic orthosis (Dynamic Traction Splint by Artificial Muscle, DTSaM) to reproduce DTM. This study analyzed the automatic motion of the wrist joint using a three-dimensional motion analysis system to assess how closely the DTSaM replicates DTM.

Methods:

The DTSaM orthosis incorporates two McKibben-type rubber artificial muscles, and measurements were performed using image analysis software and a three-dimensional motion analysis system. The wrist radial angle (WRA) was defined as the angle between the line connecting the head of the index finger metacarpal to the radial styloid process and the line connecting the radial styloid process to the lateral epicondyle of the humerus. WRAs were investigated from 60° of palmar flexion to 60° of dorsiflexion.

Results:

For dorsiflexion, comparisons of radial deviation and wrist ulnar angle (WUA) between the motion obtained using the DTSaM orthosis and active DTM showed a significant difference (P <0.05) at 30° and 60°, respectively. For palmar flexion, the same comparison showed a significant difference for both the ulnar and radial deviations (30°, P <0.05; and 60°, P <0.01, respectively). Furthermore, WUA showed a significant difference at 50° (P <0.05). Intraclass correlation coefficient analyses yielded good reliability with an average value of ≥0.8.

Conclusion:

The DTSaM orthosis produces a motion similar to the DTM. It is hoped that the use of the DTSaM orthosis will help to shorten the treatment period for patients with wrist disease.

Indices reflecting muscle contraction performance during exercise based on a combined electromyography and mechanomyography approach

Electromyography (EMG) and mechanomyography (MMG) have been used to directly evaluate muscle function through the electromechanical aspect of muscle contraction. The purpose of this study was to establish new absolute indices to describe muscle contraction performance during dynamic exercise by combining EMG and displacement MMG (dMMG) measured simultaneously using our previously developed MMG/EMG hybrid transducer system. Study participants were eight healthy male non-athletes (controls) and eight male athletes. EMG and dMMG of the vastus medialis were measured for 30 s during four cycles of recumbent bicycle pedaling (30, 60, 90, and 120 W) and on passive joint movement. Total powers were calculated based on the time domain waveforms of both signals. Muscle contraction performance was verified with the slope of regression line (SRL) and the residual sum of squares (RSS) obtained from EMG and dMMG correlation. EMG and dMMG has increased with the work rate. Force and EMG were similar between groups, but dMMG showed a significant difference with load increase. Athletes had significantly higher SRL and significantly lower RSS than controls. The average value divided by SRL and RSS was higher in athletes than in controls. The indices presented by the combined approach of EMG and dMMG showed a clear contrast between the investigated groups and may be parameters that reflect muscle contraction performance during dynamic exercise.

Molecular Structure of Gardenia Blue Pigments by Reaction of Genipin with Benzylamine and Amino Acids

Genipin was reacted with benzylamine and several amino acids to prepare gardenia blue (GB). The time-course of GB formation with benzylamine was monitored by high-performance liquid chromatography (HPLC), liquid chromatography time-of-flight mass spectrometry (LC-TOFMS), and ¹H and ¹³C NMR measurements. In this experiment, we determined the molecular structures of some intermediates using accurate masses and additional NMR techniques such as heteronuclear multiple bond correlation (HMBC). GBs with amino acids (GB-AAs) were characterized by both liquid and solid-state NMR measurements. Interestingly, many significant peaks appeared in the solid-state NMR spectra, although the ¹³C NMR spectra from solution samples did not show any distinct peaks. Therefore, we determined that GB-AAs had an alternating copolymer structure composed of methyne and 5H-2-pyrindine, which was substituted by amino acids at N atom and linked with methyne at 5 and 7 positions. To confirm this molecular structure, the pyrolysis gas chromatography-mass spectrometry (GC-MS) measurement of GB-AAs was carried out, and 5H-2-pyrindine and its methyl derivatives were formed as main pyrolysis products from the polymer chains.

Incidence rate and risk factors for radiographic hip osteoarthritis in Japanese men and women: a 10-year follow-up of the ROAD study

OBJECTIVE

To investigate the incidence and progression rate of radiographic hip osteoarthritis (OA) and its risk factors in Japanese men and women using a large-scale population of a nationwide cohort study, Research on Osteoarthritis/osteoporosis Against Disability (ROAD).

METHODS

From the baseline survey of the ROAD study, 2,975 participants (1,043 men and 1,932 women) aged 23-94 years (mean, 70.2 years) living in urban, mountainous, and coastal communities were followed up with hip radiography at 3, 7, and 10 years (mean follow-up, 7.1 years). Radiographs were scored using the Kellgren/Lawrence (K/L) grading system, and radiographic hip OA was defined as K/L ≥ 2. The incidence and progression rate of hip OA were examined. Acetabular dysplasia was defined as a central-edge angle <20°. Cox's proportional hazard model was used to assess risk factors for incident and progressive radiographic hip OA.

RESULTS

The incidence rate of radiographic hip OA was 5.6/1,000 person-years and 8.4/1,000 person-years in men and women, respectively. The progression rate of hip OA was 2.2/1,000 person-years and 6.0/1,000 person-years in men and women, respectively. The significant risk factors for incident hip OA were age, obesity, and acetabular dysplasia at baseline (hazard risk [HR] 1.05, 95% confidence interval [CI] 1.03-1.08; 1.78, 1.10-2.75; 2.06, 1.30-3.17, respectively). The significant risk factors for progressive hip OA were baseline hip pain and acetabular dysplasia (HR 5.68, 95%CI 1.07-22.61; 14.78, 3.66-56.06, respectively).

CONCLUSION

Continued longitudinal surveys of the ROAD study will contribute to knowledge about and potential prevention of incident and progressive hip OA.

Limited Survey of Residual Tetracyclines in Tissues Collected from Diseased Animals in Aichi Prefecture, Japan

Tissues were collected to survey the actual conditions of tetracycline antibiotics (TCs) residues in slaughtered animals that did not pass inspection at slaughterhouses in Aichi Prefecture, Japan, because of the presence of disease symptoms. Tissues were analyzed by liquid chromatography. Among 271 samples, 49 (18.1%) were positive for oxytetracycline (OTC), 5 (1.8%) for chlortetracycline (CTC), and 5 (1.8%) for doxycyclfne (DC), respectively. One sample (cattle kidney) was positive for both OTC and DC. However, tetracycline was not detected in any samples. Percentage frequencies of TCs residues were 29.1% (37/127) and 15.2% (22/144) for cattle and hogs, respectively. Kidney samples showed higher incidence of TCs residues and 1.5-7 times higher residual concentrations than liver and miscellaneous samples.

Improvement of Chemical Analysis of Antibiotics. Part XIX1: Determination of Tetracycline Antibiotics in Milk by Liquid Chromatography and Thin-Layer Chromatography/Fast Atom Bombardment Mass Spectrometry

A precise liquid chromatographic (LC) determination with high sensitivity and a reliable mass spectrometric (MS) confirmation were established for the determination of tetracycline antibiotics (TCs) in milk. The determination of the TCs was based on C18 cartridge cleanup followed by LC separation. Recoveries of TCs from milk fortified at 20 ppb were 73.0–81.8%, and coefficients of variation were 2.6–4.6%. With this method, concentrations of oxytetracycline and tetracycline as low as 10 ppb and chlortetracycline and doxycycline as low as 20 ppb were determined readily. Thin-layer chromatography (TLC)Zfast atom bombardment (FAB) MS with a condensation technique was used to confirm TCs in milk. After the C18 cartridge cleanup, separation on a C18 TLC plate, and application of the sample condensation technique, FAB mass spectra were measured. TCs in milk at 50 ppb were reliably confirmed by TLC/FABMS.

Analysis of Methyl Isothiocyanate in Wine by Gas Chromatography with Dual Detection

Methyl isothiocyanate (MITC) was extracted from a 5 mL wine sample with 2 mL dichloromethane, and the extract was washed with 5% sodium chloride solution. MITC was determined by gas chromatography with a dual nitrogen-phosphorus detector (NPD) and a flame photometric detector (FPD, S mode) (DB-210 column, 30 m × 0.53 mm id, column temperature, 70°C). The limit of detection and quantitation of MITC with NPD–GC were 0.003 and 0.01 ppm, respectively. Average recoveries of MITC added to wine at 1 and 0.1 ppm were over 95%. This method is simple and rapid for routine analysis of MITC in wine.

Chlortetracycline, Oxytetracycline, and Tetracycline in Edible Animal Tissues, Liquid Chromatographic Method: Collaborative Study

Thirteen laboratories analyzed samples of edible animal tissues for tetracycline residues. The method included extraction of analytes into buffer, elution from a C18 solid-phase extraction (SPE) cartridge, and reversed-phase liquid chromatographic (LC) analysis, including use of a confirmation column. An additional laboratory, using an alternative LC assay based on a different sample cleanup, also analyzed the samples. Results showed the 2 methods are comparable. The LC method for determination of cholortetracycline, oxytetracycline, and tetracycline in edible animal tissues has been adopted by AOAC INTERNATIONAL. Results from 13 laboratories indicate that the method under study provides generally better results at the higher concentrations tested than at concentrations near the detection limit and that there is less problem with interferences in muscle tissue than in kidney. The method can achieve reliable results for analytes and matrixes studied at concentrations from 0.1 to 0.6 ppm and above, depending on the analyte-matrix combination, with generally better performance to be expected with muscle than with kidney. The poorer performance for fortified samples, particularly kidney, was attributed to additional homogenization steps required to prepare these samples. Recovery of analytes from different

Preparation of Samples for Gas Chromatography/Mass Spectrometry Analysis of Phthalate and Adipate Esters in Plasma and Beverages by Steam Distillation and Extraction

Phthalate and adipate esters are present in relatively large amounts in the environment, resulting in their large blank values at analysis and making precise analysis difficult. We developed a highly sensitive analytical method for phthalate and adipate esters in plasma and beverages by lowering the blank values that interfere with analysis. The method uses a closed distillation cleanup system in which steam distillation and extraction are performed simultaneously. The recoveries from beverages and plasma were both satisfactory, ranging from 90.2 to 118.3%, relative standard deviation (RSD) = 2.8–5.3%, and 96.2–134.4%, RSD = 2.2–6.5%, respectively. The detection limits of dibutyl phthalate and di-2-ethyl hexyl phthalate were 5 ng/mL, and those of diethyl phthalate, butyl benzyl phthalate, and di-2-ethyl hexyl adipate were 10 ng/mL in rabbit plasma and beverages.

Survey of Residual Tetracycline Antibiotics and Sulfa Drugs in Kidneys of Diseased Animals in the Aichi Prefecture, Japan (1995–1999)

Animal kidneys were collected in order to survey the incidence of tetracycline (TC) antibiotics and sulfa (SA) drug residues in slaughtered animals that did not pass inspection for human consumption by the Japanese Food Sanitation Law and the Meat Inspection Law at the slaughterhouses in Aichi Prefecture, Japan, from April 1995 to March 2000. The kidneys were analyzed by AOAC Official Method 995.09 for TCs and our previously reported liquid chromatographic method for SAs. Among 292 animals (94 cattle and 198 pigs), 106 (36.6%) and 41 (14.0%) contained TCs and SAs, respectively, including chlortetracycline, 59 (20.2%); oxytetracycline, 47 (16.1%); sulfamonomethoxine, 35 (12.0%); sulfadimethoxine and sulfamethoxazole, each 2 (0.7%); and sulfamerazine and sulfisoxazole, each 1 (0.3%). A small number of animals (5 cattle and 9 pigs) contained more than one drug residue. The frequency of residue detections was significantly higher for TCs than SAs in both cattle and pig kidneys (p &lt; 0.001).

Survey of Residual Tetracyclines in Kidneys of Diseased Animals in Aichi Prefecture, Japan (1985–1997)

A survey was conducted to determine the incidence of tetracycline antibiotic (TCAs) residues in the kidneys of slaughtered animals that did not pass inspection for human consumption by the Japanese Food Sanitation Law and the Meat Inspection Law at the slaughterhouses in Aichi Prefecture, Japan, from April 1985 to March 1998. The kidneys were analyzed by the AOAC Official Method 995.09. Among 424 animals (147 cattle and 277 pigs), 131 (30.9%) were contaminated with TCAs, including 69 (16.3%) with chlortetracycline (CTC), 61 (14.4%) with oxytetracycline (OTC), 3 (0.7%) with tetracycline (TC), and 1 (0.2%) with doxycycline (DC). One sample (cattle kidney) was contaminated with both OTC and DC. The frequencies of OTC and TC residues were significantly higher ( p&lt; 0.05) in cattle than in pigs, whereas, the frequency of CTC was significantly higher ( p&lt; 0.01) in pigs. Pig kidney samples collected in 1991–1997 had significantly higher incidences of TCAs and CTC ( p&lt; 0.01) residues than those in 1985–1986.

Do sarcopenia and/or osteoporosis increase the risk of frailty? A 4-year observation of the second and third ROAD study surveys

In this 4-year follow-up study including 1083 subjects (≥ 60 years), the prevalence of frailty was estimated to be 5.6%; osteoporosis was found to be significantly associated with frailty. Moreover, the presence of both osteoporosis and sarcopenia increased the risk of frailty compared to the presence of osteoporosis or sarcopenia alone.

INTRODUCTION

This study aims to examine the contribution of sarcopenia and osteoporosis to the occurrence of frailty using 4-year follow-up information of a population-based cohort study.

METHODS

The second survey of the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) study was conducted between 2008 and 2010; 1083 subjects (aged ≥ 60 years, 372 men, 711 women) completed all examinations on frailty, sarcopenia, and osteoporosis, which were defined using Fried's definition, Asian Working Group for Sarcopenia criteria, and WHO criteria, respectively. The third survey was conducted between 2012 and 2013; 749 of 1083 individuals enrolled from the second survey (69.2%, 248 men, 501 women) completed assessments identical to those in the second survey.

RESULTS

The prevalence of frailty in the second survey was 5.6% (men, 3.8%; women, 6.6%). The cumulative incidence of frailty was 1.2%/year (men, 0.8%/year; women, 1.3%/year). After adjustment for confounding factors, logistic regression analysis indicated that osteoporosis was significantly associated with the occurrence of frailty (odds ratio, 3.07; 95% confidence interval, 1.26-7.36; p = 0.012). Moreover, the occurrence of frailty significantly increased according to the presence of osteoporosis and sarcopenia (odds ratio vs. neither osteoporosis nor sarcopenia: osteoporosis alone, 2.50; osteoporosis and sarcopenia, 5.80).

CONCLUSIONS

Preventing osteoporosis and coexistence of osteoporosis and sarcopenia may help reduce the risk of frailty.

Effect of different surgical procedures on the accuracy of prediction of the plasma concentration of fentanyl: comparison between mastectomy and laparoscopic prostatectomy

Background

The accuracy of simulation-predicted fentanyl concentration in different types of surgical procedure is not fully understood. We wished to estimate the effect of different types of surgical procedure on the accuracy of such simulations.

Findings

Fifty patients who had undergone elective mastectomy or laparoscopic prostatectomy (American Society of Anesthesiologists physical status = I–II) were enrolled. Anesthesia was maintained throughout surgery with sevoflurane and a bolus infusion of fentanyl. A maintenance infusion was administered with 8 mL/kg/h Ringer’s acetate solution from the start of anesthesia to completion of blood sampling. An infusion to compensate for blood loss was administered (one to two volumes of hydroxyethyl starch). A blood sample was drawn every 30 min during anesthesia.

We measured the plasma concentration of fentanyl in 358 samples from 50 patients. The plasma concentration of fentanyl was correlated significantly with the simulated predicted fentanyl concentration (r = 0.734, P < 0.01) but 36.0% of all samples had a difference greater than ±0.5 ng/mL. Approximately 0.3 ng/mL of a fixed bias was shown throughout mastectomy. During laparoscopic prostatectomy, the fixed bias gradually became negative from ≈0.3 to −0.3 ng/mL as the sampling stage proceeded.

Conclusions

The predicted concentration of fentanyl was significantly correlated with the plasma concentration of fentanyl (r = 0.734). However, there were different patterns of a fixed bias between mastectomy and laparoscopic prostatectomy groups. We should pay attention to this tendency among different surgical procedures.

Trial registration

UMIN000005110

Electronic supplementary material

The online version of this article (doi:10.1186/s40981-017-0097-2) contains supplementary material, which is available to authorized users.

Perceptions of dental students in Japanese national universities about studying abroad

PURPOSE

Dental faculties in Japan have organised many short-term international exchange programs to enable their undergraduates to study abroad. However, not many students apply for those programs. In this present study, we attempted to clarify the factors that discourage undergraduate dental students from studying abroad.

METHODS

We administered a questionnaire survey to 512 undergraduate dental students in three national universities located in different areas in Japan.

RESULTS

Although 61.7% of the participants expressed interest in studying abroad, only 19.1% of them had prior experiences of study abroad or plans to do so. Their main worries were about lack of sufficient language ability in academic fields. Comparing those who were interested in studying abroad with those who were not revealed significant differences regarding their concern about lack of language ability and lack of specialised knowledge in dentistry. Participants who did not want to study abroad indicated that they did not perceive a purpose in doing so and cited not having foreign friends as a problem. Household income was significantly correlated with concerns about overall expenses.

CONCLUSION

Overall, language ability and academic knowledge appeared to be the two strongest factors affecting dental students' consideration of studying abroad. Dental schools in Japan can use the findings of this study to improve their undergraduate exchange programs in such a way as to stimulate greater interest amongst their students.

Radiographic measurements of the hip joint and their associations with hip pain in Japanese men and women: the Research on Osteoarthritis/osteoporosis Against Disability (ROAD) study

OBJECTIVE

To investigate radiographic measurements of the hip joint and their associations with hip pain, and the prevalence of acetabular dysplasia defined by radiographic measurements of the hip joint in Japanese men and women using the large-scale population-based cohort of the Research on Osteoarthritis/osteoporosis Against Disability (ROAD) study.

METHODS

From the baseline survey of the ROAD study (cross-sectional study), 2963 participants (1040 men, 1923 women; mean age, 70.2 years) were analyzed. All participants underwent radiographic examinations of both hips using an anteroposterior view under weight-bearing. Minimum joint space width (mJSW), central-edge (CE) angle, acetabular depth-to-width ratio (ADR), and acetabular head index (AHI) were measured. Associations between these radiographic measurements and hip pain were assessed by calculating odds ratios (ORs) using multivariable logistic-regression analysis. Acetabular dysplasia was defined as a CE angle <20°.

RESULTS

Mean radiographic measurements of the hip joint for men were: mJSW, 3.8 mm; CE angle, 30.6°; ADR, 262.1 per 1000; and AHI, 81.4%. For women, these values were: mJSW, 3.4 mm; CE angle, 29.9°; ADR, 262.7 per 1000; and AHI, 81.2%. Associations were seen between hip pain and each of mJSW, CE angle, ADR, and AHI (OR 4.52, 95% confidence interval 3.45-5.97; 1.14, 1.11-1.18; 1.31, 1.24-1.40; and 1.15, 1.12-1.18, respectively). Acetabular dysplasia showed an overall prevalence of 13.9%, and was significantly more prevalent in women than in men (P = 0.012).

CONCLUSION

The present study of radiographic measurements of the hip joint showed that mJSW, CE angle, ADR, and AHI were associated with hip pain.

A High-Fat and High-Cholesterol Diet Induces Cardiac Fibrosis, Vascular Endothelial, and Left Ventricular Diastolic Dysfunction in SHRSP5/Dmcr Rats

AIM

Non-alcoholic steatohepatitis (NASH) increases cardiovascular risk regardless of risk factors in metabolic syndrome. However, the intermediary factors between NASH and vascular disease are still unknown because a suitable animal model has never been established. The stroke-prone (SP) spontaneously hypertensive rat, SHRSP5/Dmcr, simultaneously develops hypertension, acute arterial lipid deposits in mesenteric arteries, and NASH when feed with a high-fat and high-cholesterol (HFC) diet. We investigated whether SHRSP5/Dmcr affected with NASH aggravates the cardiac or vascular dysfunction.

METHOD

Wister Kyoto and SHRSP5/Dmcr rats were divided into 4 groups of 5 rats each, and fed with a SP or HFC diet. After 8 weeks of HFC or SP diet feeding, glucose and insulin resistance, echocardiography, blood biochemistry, histopathological staining, and endothelial function in aorta were evaluated.

RESULTS

We demonstrate that SHRSP5/Dmcr rats fed with a HFC diet presented with cardiac and vascular dysfunction caused by cardiac fibrosis, endothelial dysfunction, and left ventricular diastolic dysfunction, in association with NASH and hypertension. These cardiac and vascular dysfunctions were aggravated and not associated with the presence of hypertension, glucose metabolism disorder, and/or obesity.

CONCLUSIONS

SHRSP5/Dmcr rats may be a suitable animal model for elucidating the organ interaction between NASH and cardiac or vascular dysfunction.

Body weight and dysautonomia in early Parkinson's disease

OBJECTIVES

Patients with Parkinson's disease (PD) begin to lose weight several years before diagnosis, which suggests weight variation is associated with some factor(s) that precede the onset of motor symptoms. This study aimed to investigate the association of autonomic nervous system with body weight in patients with PD.

MATERIALS AND METHODS

The subjects were 90 patients with early de novo PD. We examined the associations of body mass index (BMI) with sympathetic nervous activity reflected in orthostatic intolerance or cardiac uptake of ¹²³ I-metaiodobenzylguanidine and parasympathetic nervous activity reflected in constipation or heart rate variability (HRV).

RESULTS

Twelve patients (13.3%) were overweight (BMI>25 kg/m² ), 62 patients (68.9%) were normal-weight (18.5≦BMI<25 kg/m² ), and 16 patients (17.8%) were underweight (BMI<18.5 kg/m² ). Underweight patients had greater disease severity and decrease in blood pressure on head-up tilt-table testing, higher cardiac washout ratio of ¹²³ I-metaiodobenzylguanidine, and lower HRV and complained of constipation more often than those with normal-weight or overweight patients. On multiple regression analyses, the correlation of these variables with BMI maintained statistical significance after adjustment for age, sex, symptom duration, and motor subtype.

CONCLUSIONS

Dysautonomia and disease severity are closely related to body weight independently of age, sex, symptom duration, and motor subtype. Dysautonomia may play a partial role on weight variation in the early stage of PD.

Estimating the minimum stimulation frequency necessary to evoke tetanic progression based on muscle twitch parameters

The summation of the muscle force caused by an increase in the firing rate is named a tetanic contraction (tetanus), and the minimum stimulation frequency necessary to evoke an unfused/fused tetanus is related to the contraction time (CT) and relaxation time (RT) of the twitch. In particular, the fusion index (FI) is a very useful indicator, and it is used to evaluate the change in the muscle fiber component ratio. However, the measurement of the FI is invasive, because most patients experience pain during the electrical stimulation for tetanus. We expect that the twitch parameters CT and RT can substitute for the FI in the future. We found that the minimum stimulation frequency necessary to evoke the unfused/fused tetanus can be estimated from the twitch parameters as a first step. The results showed that (1) the minimum stimulation frequencies calculated from twitch parameters during unfused/fused tetanus were very similar to those calculated from FI parameters, and (2) they were also strongly correlated with FI parameters regardless of fiber components. The basic characteristics of tetanic progression in different fiber types could be estimated from twitch parameters.

Is osteoporosis a predictor for future sarcopenia or vice versa? Four-year observations between the second and third ROAD study surveys

In a 4-year follow-up study that enrolled 1099 subjects aged ≥60 years, sarcopenia prevalence was estimated at 8.2%. Moreover, the presence of osteoporosis was significantly associated with short-term sarcopenia occurrence, but the reciprocal relationship was not observed, suggesting that osteoporosis would increase the risk of osteoporotic fracture and sarcopenia occurrence.

INTRODUCTION

The present 4-year follow-up study was performed to clarify the prevalence, incidence, and relationships between sarcopenia (SP) and osteoporosis (OP) in older Japanese men and women.

METHODS

We enrolled 1099 participants (aged, ≥60 years; 377 men) from the second survey of the Research on Osteoarthritis/Osteoporosis against Disability (ROAD) study (2008-2010) and followed them up for 4 years. Handgrip strength, gait speed, skeletal muscle mass, and bone mineral density were assessed. SP was defined according to the Asian Working Group for Sarcopenia. OP was defined based on the World Health Organization criteria.

RESULTS

SP prevalence was 8.2% (men, 8.5%; women, 8.0%) in the second survey. In those with SP, 57.8% (21.9%; 77.6%) had OP at the lumbar spine L2-4 and/or femoral neck. SP cumulative incidence was 2.0%/year (2.2%/year; 1.9%/year). Multivariate regression analysis revealed that OP was significantly associated with SP occurrence within 4 years (odds ratio, 2.99; 95% confidence interval, 1.46-6.12; p < 0.01), but the reciprocal relationship was not significantly observed (2.11; 0.59-7.59; p = 0.25).

CONCLUSIONS

OP might raise the short-term risk of SP incidence. Therefore, OP would not only increase the risk for osteoporotic fracture but may also increase the risk for SP occurrence.

PGE2 Activates Cementoclastogenesis by Cementoblasts via EP4

Destruction of cementum and alveolar bone is the main causative event for the exfoliation of teeth as a consequence of periodontitis. Prostaglandin E2 (PGE2) and PGE receptor subtypes (EPs) play an important role in modulating osteoblast-mediated osteoclastogenesis; however, no information is available on the role of PGE2 and EPs in regulating cementoblast-mediated cementoclastogenesis. We hypothesized that the PGE2-EPs pathway also regulates cementoblasts’ ability to activate cementoclasts. For these studies, OCCM-30 cells (a mouse cementoblast cell line) were exposed to PGE2 and specific EP agonists. PGE2 (100 ng/mL) and EP4 agonist (1 μM) up-regulated RANKL and IL-6 mRNA levels, while they down-regulated OPG mRNA expression. The EP4 antagonist (1 μM) eliminated these effects of PGE2. PGE2 treatment of co-cultures of OCCM-30 cells with bone marrow cells induced TRAP-positive cells via the EP4 pathway. These findings suggest that PGE2 promotes cementoblast-mediated cementoclastogenesis by regulating the expression of RANKL and OPG via the EP4 pathway.

Electrically induced mechanomyograms reflect inspiratory muscle strength in young or elderly subjects

BACKGROUND

Respiratory muscle strength has been used as a tool for evaluating respiratory rehabilitation in chronic obstructive pulmonary disease. However, mouth pressure measurement evaluated by maximum expiratory mouth pressure (PEmax) or inspiratory mouth pressure (PImax) offers an indirect method for measuring respiratory muscle strength. We demonstrated the evaluation of diaphragm contractility using a mechanomyogram (MMG), which is the mechanical signal generated by the motion of the diaphragm induced by the electric stimulation of the phrenic nerve.

METHODS

Study participants were 21 young and 20 elderly subjects with no symptoms of respiratory disease. The elderly subjects were divided into non-smoker or smoker groups. The smoker group was defined as subjects having a Brinkman Index of greater than 300. We measured basic spirometric parameters, mouth pressure (PEmax, PImax), and diaphragmatic MMG.

RESULTS

Diaphragmatic MMG showed more clear contrast between young subjects and elderly non-smoker or smoker subjects than the conventional method for respiratory muscle contraction (PEmax, PImax). In addition, the diaphragmatic MMG strongly correlated with inspiratory muscle strength.

CONCLUSIONS

Diaphragmatic MMG may reflect diaphragmatic contractility more directly and sensitively than the conventional method.

Changes of superoxide dismutase activity and ascorbic acid in focal cerebral ischaemia in rats

Free radical reactions are supposed to cause ischaemic brain damage, and active oxygens can initiate these chains reaction. If active oxygens play important roles in ischaemic brain damage, the activity of superoxide dismutase, scavenger of superoxide anion, is supposed to decrease in ischaemic brain. The reduced form of ascorbic acid also scavenges superoxide anion. In rat middle cerebral artery focal ischaemia, we investigated the changes in superoxide dismutase activity and the concentration of reduced ascorbate up to 48 hours. Middle cerebral artery territory of each cerebral hemisphere was homogenized. The supernatant was divided into two aliquots; one was dialysed to remove ascorbate and the other was not. The enzyme activity of the dialysed specimen from the ischaemic hemisphere did not decrease within 4 h after the arterial occlusion. The activity of the dialysed specimen from the nonischaemic side remained unchanged during the examination. Reduced ascorbate levels in nondialysed samples showed similar changes to the superoxide dismutase activities in the dialysed samples. Our data suggest that ascorbic acid may exert the enzyme activity and that the enzyme activity remains at the normal level in the early phase of ischaemia despite the irreversible ischaemic changes that take place within 4 h after the onset of ischaemia.

Change of xanthine dehydrogenase and xanthine oxidase activities in rat brain following complete ischaemia

We studied the activities of xanthine dehydrogenase and xanthine oxidase in rat forebrain after complete ischaemia. Complete ischaemia was induced by decapitation after transcardiac infusion with saline. The activities of xanthine dehydrogenase and xanthine oxidase immediately after ischaemia were 93.3 +/- 38.7 and 18.8 +/- 7.7 microU/mg protein, respectively, and at 24 h after ischaemia were 183.5 +/- 75.1 and 60.8 +/- 15.2 microU/mg protein, respectively. The ratios of xanthine dehydrogenase/xanthine oxidase immediately and 24 h after ischaemia were 5.04 +/- 1.03 and 3.04 +/- 0.99, respectively. These data indicate that xanthine dehydrogenase and xanthine oxidase activities were maintained even 24 h after complete ischaemia. Conversion of xanthine dehydrogenase to xanthine oxidase proceeds slowly during complete ischaemia.

Pneumatic-type dynamic traction and flexion splint for treating patients with extension contracture of the metacarpophalangeal joint

BACKGROUND

Collateral ligament shortening causes extension contractures of the metacarpophalangeal joint, and dynamic flexion splinting has been widely used to treat these contractures; however, there are various problems with these approaches. We developed a novel, pneumatic-type dynamic traction and flexion splint to solve these problems.

CASE DESCRIPTION AND METHODS

A total of 25 fingers were treated with the dynamic traction and flexion splint for 8 weeks. Every 2 weeks, the average metacarpophalangeal joint flexion angle, total active motion, grasp strength, and pain scores were assessed.

FINDINGS AND OUTCOMES

The finger flexion angle was significantly greater at the final evaluation, starting after 6 weeks of treatment (p < 0.05), than prior to treatment. Similarly, the total active motion results improved significantly over 8 weeks.

CONCLUSIONS

Our results show that use of the dynamic traction and flexion splint improves patient finger functioning and flexural angle.

CLINICAL RELEVANCE

The dynamic traction and flexion (DTF) splint appears to be effective for treating patients.

Prevalence of radiographic hip osteoarthritis and its association with hip pain in Japanese men and women: the ROAD study

OBJECTIVE

Although hip osteoarthritis (OA) is a major cause of hip pain and disability in elderly people, few epidemiologic studies have been performed. We investigated the prevalence of radiographic hip OA and its association with hip pain in Japanese men and women using a large-scale population of a nationwide cohort study, Research on Osteoarthritis/osteoporosis Against Disability (ROAD).

METHODS

From the baseline survey of the ROAD study, 2975 participants (1043 men and 1932 women), aged 23-94 years (mean 70.2 years), living in urban, mountainous, and coastal communities were analyzed. The radiographic severity at both hips was determined by the Kellgren/Lawrence (K/L) grading system. Radiographic hip OA was defined as K/L ≥ 2, and severe radiographic hip OA as K/L ≥ 3.

RESULTS

The crude prevalence of radiographic hip OA was 18.2% and 14.3% in men and women, respectively, that of severe radiographic hip OA was 1.34% and 2.54%, and that of symptomatic K/L ≥ 2 OA was 0.29% and 0.99%, respectively. The crude prevalence of hip OA, including severe OA, was not age-dependent in men or women. Male sex was a risk factor for radiographic hip OA, whereas female sex was a risk factor for severe radiographic hip OA and hip pain. Compared with K/L = 0/1, hip pain was significantly associated with K/L ≥ 3, but not with K/L = 2.

CONCLUSION

The present cross-sectional study revealed the prevalence of radiographic hip OA and severe hip OA in Japanese men and women. Hip pain was strongly associated with K/L ≥ 3.

Factors affecting changes in the serum levels of 25-hydroxyvitamin D: a 3-year follow-up of the ROAD study

In this 3-year population-based cohort study, among 1346 subjects, the mean annual change in the serum 25-hydroxyvitamin D levels was 7.6 %/year, which tended to increase during the 3-year period. Multivariate regression analysis indicated that the L2-4 bone mineral density and total daily energy intake were significant independent associated factors.

INTRODUCTION

The aim of this study was to clarify the change rate of the serum levels of 25-hydroxyvitamin D (25D) and the associated factors in a general Japanese population during a 3-year period.

METHODS

The baseline survey of Research on Osteoarthritis/osteoporosis Against Disability study (ROAD), a large-scale population-based cohort study, was performed between 2005 and 2007, and a follow-up survey was repeated 3 years later. Among 1690 participants at baseline, the change rate of the serum 25D levels were assessed in 1346 individuals (79.6 %; 458 men and 888 women) who completed measurements of 25D at both the baseline and follow-up examinations. The change rate was calculated, and the factors associated with the changes in the 25D levels were determined using multivariate regression analysis after adjustment for age, gender, body mass index, participated month, and regional differences at baseline.

RESULTS

The mean (standard deviation) change rate of the 25D levels in all subjects was 7.6 (13.3) %/year (men, 8.2 [12.4] %/year; women, 7.3 [13.7] %/year). Multivariate regression analysis indicated that higher bone mineral density at lumbar spine L2-4 (p = 0.05) and total daily energy intake (p = 0.04) were significantly associated with the change rate of the 25D levels.

CONCLUSIONS

The serum levels of 25D tended to increase over the 3-year period, and higher lumbar bone mineral density and daily energy intake were found to be associated with increases in the 25D levels over time.