Video-based Detection of Freezing of Gait in Daily Clinical Practice in Patients with Parkinsonism.

Freezing of gait (FoG) is a prevalent symptom among individuals with Parkinson's disease and related disorders. FoG detection from videos has been developed recently; however, the process requires using videos filmed within a controlled environment. We attempted to establish an automatic FoG detection method from videos taken in uncontrolled environments such as in daily clinical practices. Motion features of 16 patients were extracted from timed-up-and-go test in 109 video data points, through object tracking and three-dimension pose estimation. These motion features were utilized to form the FoG detection model, which combined rule-based and machine learning-based models. The rule-based model distinguished the frames in which the patient was walking from those when the patient has stopped, using the pelvic position coordinates; the machine learning-based model distinguished between FoG and stop using a combined one-dimensional convolutional neural network and long short-term memory (1dCNN-LSTM). The model achieved a high intraclass correlation coefficient of 0.75-0.94 with a manually-annotated duration of FoG and %FoG. This method is novel as it combines object tracking, 3D pose estimation, and expert-guided feature selection in the preprocessing and modeling phases, enabling FoG detection even from videos captured in uncontrolled environments.

Two-minute standing endurance test for axial postural abnormalities in patients with Parkinson's disease.

BACKGROUND: Photo-based measurement methods are used to assess axial postural abnormalities (PA) in Parkinson's disease (PD). However, they capture only moments in time. We developed the 2-minute standing endurance test (2 M-SET), which specifically captures temporal changes in posture, as a novel dynamic method for measuring axial PA in patients with PD. RESEARCH QUESTION: This study aimed to verify the effectiveness and validity of the 2 M-SET for capturing temporal changes in axial PA in patients with PD. METHODS: Twenty-eight patients with PD participated. The participants attempted to maintain an upright posture for 2 minutes during three tasks: standing, stepping in place, and walking. The rate of change in postural angle was recorded at 10-second intervals. Based on the results, the 2 M-SET was developed. Therapists evaluated the 2 M-SET using the NeuroPostureApp© to measure anterior trunk flexion (ATF) angles and lateral trunk flexion (LTF) angles at 0, 10, 30, 60, and 120 seconds. To assess reliability, the congruence between the measurements obtained by the therapists and those obtained using a three-dimensional motion-analysis system was examined. For validity, we assessed whether the ATF and LTF angles measured by the therapists could accurately capture postural changes at regular intervals over time. RESULTS: The average postural changes over 2 minutes for the standing, stepping in place, and gait tasks were 59.2±83.5%, 37.6±30.7%, and 45.4±50.6%, respectively. The intraclass correlation coefficients showed high reliability, with values of 0.985 and 0.970 for the ATF and LTF angles, respectively. SIGNIFICANCE: The results of our proposed 2 M-SET method, which uses temporal photo-based measurements to assess the patient's ability to maintain an upright standing position for 2 minutes, demonstrate the potential to capture temporal changes in axial PA. DATA AVAILABILITY STATEMENT: The data supporting the findings of this study are available upon reasonable request and approval from the local ethics committee.

[A Study on the Scientific Reliability of Notification Data in the Foods with Function Claims].

We conducted a comprehensive survey of Foods with Function Claims (FFC) submitted from April to August 2022 to examine the scientific reliability of the systematic review (SR), which is the basis for functional claims. The results of the review of 611 functional claims for 398 products showed that there were 121 functionally active substances and 87 health claims (Hc) that were labeled, with some functionally active substances having multiple functions. SRs, meta-analyses, and clinical studies were submitted as the basis of functionality for 87%, 10%, and 3% of the reports, respectively. Of these SRs, 39% of the SRs included a single paper. In 67% of the SRs with a single paper included, some of the authors of the included paper and the person who conducted the SR had the same affiliation, which raises concerns about conflicts of interest. The median of clinical trial participants in papers included for SR was relatively small, 38, and the smallest total number of SRs was 6. Thus, it was shown that there are many SRs for FFC that are based on only a single paper or a small-scale clinical trial and that lack reliability as scientific evidence.

Effects of energy loads on energy and nutrient absorption rates and gut microbiome in humans: A randomized crossover trial.

OBJECTIVE: This study aimed to determine the effects of different energy loads on the gut microbiota composition and the rates of energy and nutrient excretion via feces and urine. METHODS: A randomized crossover dietary intervention study was conducted with three dietary conditions: overfeeding (OF), control (CON), and underfeeding (UF). Ten healthy men were subjected to each condition for 8 days (4 days and 3 nights in nonlaboratory and laboratory settings each). The effects of dietary conditions on energy excretion rates via feces and urine were assessed using a bomb calorimeter. RESULTS: Short-term energy loads dynamically altered the gut microbiota at the α-diversity (Shannon index), phylum, and genus levels (p < 0.05). Energy excretion rates via urine and urine plus feces decreased under OF more than under CON (urine -0.7%; p < 0.001, urine plus feces -1.9%; p = 0.049) and UF (urine -1.0%; p < 0.001, urine plus feces -2.1%; p = 0.031). However, energy excretion rates via feces did not differ between conditions. CONCLUSIONS: Although short-term overfeeding dynamically altered the gut microbiota composition, the energy excretion rate via feces was unaffected. Energy excretion rates via urine and urine plus feces were lower under OF than under CON and UF conditions.

Sustained response in early responders to safinamide in patients with Parkinson's disease and motor fluctuations: A post hoc analysis of the SETTLE study.

Safinamide is a selective, reversible, monoamine oxidase B inhibitor for the treatment of patients with Parkinson's disease (PD) and motor fluctuations. This was a post hoc analysis of the SETTLE study, in which patients with PD and motor fluctuations were randomly assigned to 24-week treatment with safinamide (50 mg/day for 2 weeks, increased to 100 mg/day if tolerated) or placebo. In the present analysis, responders were defined according to their treatment responses at Week 2 and Week 24 based on changes in ON-time without troublesome dyskinesia from baseline with cutoffs of 1 hour. It was found that 81% (103/127) of the responders at Week 2 maintained the response through Week 24 in the safinamide group. Other outcomes did not necessarily coincide with the ON-time response; however, "Early" responders who showed a treatment response at both Week 2 and Week 24 had substantial improvements from baseline in OFF-time, UPDRS Part II and III scores, and PDQ-39 summary index scores through Week 24. The safinamide group had a higher proportion of early responders than the placebo group (39% vs 20%, p < 0.0001). At baseline, early responders in the safinamide group had significantly higher UPDRS Part II and III scores, shorter ON-time, and longer OFF-time than the other responder populations. In conclusion, the results of the present post hoc analysis suggest that patients with a short ON-time, severe motor symptoms, and highly compromised activities of daily living can benefit from safinamide early in treatment and over the long term.

Safinamide as an Adjunct to Levodopa in Asian and Caucasian Patients With Parkinson's Disease and Motor Fluctuations: A Post Hoc Analysis of the SETTLE Study.

OBJECTIVE: Safinamide is a selective, reversible monoamine oxidase B inhibitor with demonstrated efficacy and tolerability in placebo-controlled studies and is clinically useful for patients with motor fluctuations. This study evaluated the efficacy and safety of safinamide as a levodopa adjunct therapy in Asian patients with Parkinson's disease. METHODS: Data from 173 Asian and 371 Caucasian patients from the international Phase III SETTLE study were included in this post hoc analysis. The safinamide dose was increased from 50 mg/day to 100 mg/day if no tolerability issues occurred at week 2. The primary outcome was the change from baseline to week 24 in daily ON-time without troublesome dyskinesia (i.e., ON-time). Key secondary outcomes included changes in Unified Parkinson's Disease Rating Scale (UPDRS) scores. RESULTS: Safinamide significantly increased daily ON-time relative to placebo in both groups (least-squares mean: 0.83 hours, p = 0.011 [Asians]; 1.05 hours, p < 0.0001 [Caucasians]). Motor function relative to placebo (UPDRS Part III) improved significantly in Asians (-2.65 points, p = 0.012) but not Caucasians (-1.44 points, p = 0.0576). Safinamide did not worsen Dyskinesia Rating Scale scores in either subgroup, regardless of the presence or absence of dyskinesia at baseline. Dyskinesia was largely mild for Asians and moderate for Caucasians. None of the Asian patients experienced adverse events leading to treatment discontinuation. CONCLUSION: Safinamide as a levodopa adjunct is well tolerated and effective in reducing motor fluctuations in both Asian and Caucasian patients. Further studies to investigate the real-world effectiveness and safety of safinamide in Asia are warranted.

Safety assessment of herbal supplement components targeting hepatotoxicity and CYP3A4 induction in cell-based assay using HepG2 cells.

Herbal supplements can cause hepatotoxicity and drug interactions via hepatic cytochrome P-450 (CYP) in some cases. However, there is no simple and stable cell-based assay to conduct a screening for hepatotoxicity and CYP induction. In the present study, we selected 14 components of the herbal supplement based on our previous reports and investigated the safety of the herbal supplement components focusing on toxicity and CYP3A4 induction in a cell-based assay using HepG2. The toxicity of the components was examined by lactate dehydrogenase (LDH) and cell proliferation assays. Then, the CYP3A4 induction of the components were examined by a reporter assay using reporter vectors of CYP3A4. The vector includes the CYP3A4 proximal promoter (CYP3A4PP) and the xenobiotic-responsive enhancer module (XREM) regions. Luteolin (LU) significantly increased LDH activity and decreased cell proliferation activity that suggests LU may cause toxicity in HepG2 cells. Quercetin (QU) increased the transcriptional activity of CYP3A4 (1.5-fold of control) in the reporter assay. However, the induction of QU was slightly in comparison to the validation of the transcriptional activity of CYP3A4 treated with CYP3A4 inducers. The CYP3A4 induction of QU may not involve CYP3A4PP but involves the XREM response. Throughout our results, the method in the present study may be useful for a safety assessment of herbal supplements, primarily focusing on hepatotoxicity and CYP3A4 induction. PRACTICAL APPLICATION: Even though there are problems with herbal supplements, studies related to toxicity are not actively carried out. The present methods may apply to the safety assessment for herbal supplements and be useful for the prevention and verification of health hazards caused by herbal supplements (the summary is shown in Figure S2).

Long-term effects of safinamide adjunct therapy on levodopa-induced dyskinesia in Parkinson's disease: post-hoc analysis of a Japanese phase III study.

This post-hoc analysis investigated the long-term effects of safinamide on the course of dyskinesia and efficacy outcomes using data from a phase III, open-label 52-week study of safinamide 50 or 100 mg/day in Japanese patients with Parkinson's disease (PD) with wearing-off. Patients (N = 194) were grouped using the UPDRS Part IV item 32: with and without pre-existing dyskinesia (pre-D subgroup; item 32 > 0 at baseline [n = 81], without pre-D subgroup; item 32 = 0 at baseline [n = 113]). ON-time with troublesome dyskinesia (ON-TD) increased significantly from baseline to Week 4 in the pre-D subgroup (+ 0.25 ± 0.11 h [mean ± SE], p = 0.0355) but gradually decreased up to Week 52 (change from baseline: - 0.08 ± 0.17 h, p = 0.6224); ON-TD did not change significantly in the Without pre-D subgroup. UPDRS Part IV item 32 score increased significantly at Week 52 compared with baseline in the Without pre-D subgroup, but no UPDRS Part IV dyskinesia related-domains changed in the pre-D subgroup. Both subgroups improved in ON-time without TD, UPDRS Part III, and Part II [OFF-phase] scores. The cumulative incidence of new or worsening dyskinesia (adverse drug reaction) at Week 52 was 32.5 and 5.0% in the pre-D and Without pre-D subgroups, respectively. This study suggested that safinamide led to short-term increasing dyskinesia but may be not associated with marked dyskinesia at 1-year follow-up in patients with pre-existing dyskinesia, and that it improved motor symptoms regardless of the presence or absence of dyskinesia at baseline. Further studies are warranted to investigate this association in more details.Trial registration: JapicCTI-153057 (Registered: 2015/11/02).

Measurement Accuracy of Freezing of Gait Scoring Based on Videos.

Freezing of gait (FOG) is a common symptom in the late stages of Parkinson's disease and related disorders. Videos are the gold standard method to conduct FOG scoring; however, the measurement accuracy of FOG scoring based on videos has not been formally assessed, despite its use in previous studies. This study aimed to calculate the measurement accuracy of video-based FOG scoring. Three evaluators scored the FOG based on 157 video data points collected from 21 patients using an annotation tool. One evaluator measured the intra-rater reliability of the retest. The total duration of observed FOG, percentage of the time spent with FOG during the walking task (%FOG), and FOG phenotypes (shuffling, trembling, and complete akinesia) were evaluated. Intraclass correlation coefficients were used to determine the intra- and inter-rater reliabilities. The duration of FOG and %FOG showed good measurement accuracy for both intra-rater and inter-rater reliabilities. However, the FOG phenotypes showed poor measurement accuracy in inter-rater reliability. These results indicate that the temporal characteristics of FOG can be scored with a high degree of measurement accuracy, even with different evaluators; conversely, the FOG phenotypes need to be scored by several evaluators.

Reliability in viscosity measurement of thickening agents for dysphagia management: Are results obtained by cone-and-plate rheometers reproducible between laboratories?

Viscosity measurement using a cone-and-plate rheometer is considered to provide an objective and reliable evaluation of thickening agents for dysphagia management. Here, we showed its measurement uncertainty in the context of an inter-laboratory study. Eight test samples (i.e., four viscosity standard liquids, one xanthan gum reagent powder, and three commercial thickening agent powders) were distributed to 10 laboratories in a blinded manner. According to the same standard operating procedure, each laboratory dissolved the xanthan gum or thickening agents at four concentrations (0.5-4.0 g/100 g) and then measured their viscosity (35-803 mPa∙s). As for the viscosity of the standard liquids, the grand means were 98-100% of the certified values, and the relative standard deviations for repeatability (RSDr ) and reproducibility (RSDR ) were ca. 1% and ca. 5%, respectively, suggesting good accuracy in the measurement process. On the other hand, as for the viscosity of the thickening agents, RSDr and RSDR were ca. 2-6% and ca. 5-8%, respectively; however, heterogeneity in the preparation process comprising a manual dissolving step may increase these to near 60%. Furthermore, RSDr and RSDR of estimated additive concentrations to achieve targeted viscosities (50-500 mPa∙s) based on concentration-viscosity curves were ca. 1-3% and ca. 3-5%, respectively, with a few exceptions. These findings suggest that a strictly standardized procedure provides reliable data on the viscosity measurements for thickening agents.

Characteristics of wearing-off and motor symptoms improved by safinamide adjunct therapy in patients with Parkinson's disease: A post hoc analysis of a Japanese phase 2/3 study.

INTRODUCTION: Patients with Parkinson's disease (PD) experience various motor and non-motor symptoms. We conducted a post hoc analysis of a Japanese phase 2/3 study of safinamide (50 or 100 mg/day) in patients with Parkinson's disease and wearing-off to evaluate response according to background factors. Safinamide efficacy against major motor symptoms was also assessed. METHODS: Multiple regression analyses in safinamide-treated patients (50 or 100 mg/day) assessed changes in daily ON-time without troublesome dyskinesia (hereafter referred to as ON-time) according to baseline clinical variables. Subgroup analyses by baseline Unified Parkinson's Disease Rating Scale (UPDRS) part III score were also conducted. We evaluated cardinal motor symptoms using the UPDRS. RESULTS: In the multiple regression analysis, changes in ON-time were related to baseline non-motor symptoms (UPDRS part I score) and ON-time in the 50-mg group, but no relationships with non-motor symptoms were observed in the 100-mg group. Additionally, in the subgroup analysis of patients with more severe motor symptoms (UPDRS part III score > 20), a significant improvement in ON-time was observed only with 100 mg/day (p = 0.01). At both doses, safinamide significantly improved cardinal motor symptom scores (bradykinesia, rigidity, tremor, axial symptoms, and gait disturbances). CONCLUSIONS: The observed response profile to the 50-mg/day dose may be related to baseline non-motor symptoms, but this was not true for the 100-mg/day dose. Both safinamide doses improved major motor symptoms in levodopa-treated patients with PD.

Effects of safinamide adjunct therapy on pain in patients with Parkinson's disease: Post hoc analysis of a Japanese phase 2/3 study.

INTRODUCTION: The non-dopaminergic and dopaminergic actions of safinamide may alleviate pain in patients with Parkinson's disease (PD). We investigated the efficacy of safinamide for pain when administered as an adjunct to levodopa in Japanese patients with PD. METHODS: This was a post hoc analysis of a phase 2/3 clinical study of safinamide in Japanese patients with PD who were experiencing wearing-off. Pain was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS) Part II 'sensory symptoms' item 17, on a scale of 0-4, and the 39-item Parkinson's Disease Questionnaire (PDQ-39) 'bodily discomfort' domain score. Subgroup analyses, according to baseline symptoms and concomitant medications, were also performed. RESULTS: Least square (LS) mean changes in the UPDRS item 17 score from baseline to Week 24 in the placebo, safinamide 50-mg and safinamide 100-mg groups during the OFF phase were 0.08, -0.15 (p = 0.0133 vs placebo) and -0.18 (p = 0.0054), respectively, and during the ON phase were 0.04, -0.08 (p = 0.0529) and -0.08 (p = 0.0505), respectively. Changes from baseline to Week 24 in PDQ-39 'bodily discomfort' scores were not significantly different in safinamide groups vs placebo. The presence of moderate-to-severe bradykinesia or early-morning dystonia at baseline resulted in numerically greater effect sizes in UPDRS item 17 scores during the OFF phase. CONCLUSIONS: Safinamide 50 mg and 100 mg reduced the UPDRS item 17 score in patients with PD, especially during the OFF phase. Patients with moderate-to-severe bradykinesia and early-morning dystonia may benefit from safinamide treatment.

Dependence of the Growth Mode in Epitaxial FePt Films on Surface Free Energy.

Epitaxial thin films of L10-ordered FePt alloys are one of the most important materials in magnetic recording and spintronics applications due to their large perpendicular magnetic anisotropy (PMA). The key to the production of these required superior properties lies in the control of the growth mode of the films. Further, it is necessary to distinguish between the effect of lattice mismatch and surface free energy on the growth mode because of their strong correlation. In this study, the effect of surface free energy on the growth mode of FePt epitaxial films was investigated using MgO, NiO, and MgON surfaces with almost the same lattice constant to exclude the effect of lattice mismatch. It was found that the growth mode can be tuned from a three-dimensional (3D) island mode on MgO to a more two-dimensional (2D)-like mode on MgON and NiO. Contact angle measurements revealed that MgON and NiO show larger surface free energy than MgO, indicating that the difference in the growth mode is due to their larger surface free energy. In addition, MgON was found to induce not only a flat surface as FePt grown on SrTiO3 (STO), which has a small lattice mismatch, but also a larger PMA than that of STO/FePt. As larger lattice mismatch is favored to induce a higher PMA into the FePt films, MgO substrates are exclusively used, but 3D island growth is indispensable. This work demonstrates that tuning the surface free energy enables us to achieve a large PMA and flat film surface in FePt epitaxial films on MgO. The results also indicate that modifying the surface free energy is pertinent for the flexible functional design of thin films.

Comparison of the Diagnostic Value of Immunochromatography Kits in Corona Virus Disease 2019 Patients: A Prospective Pilot Study.

INTRODUCTION: The spread of coronavirus 2019 (COVID-19) is a serious problem all over the world. Several immunochromatography kits of the antibody for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been developed, but it is still unclear which kits have high diagnostic value. This study aims to evaluate the accuracy rate for antibody detection of each immunochromatography kit and reveal which kit has a high diagnostic value for antibody detection. METHODS: This study was carried out between 1 August 2020 and 14 October 2020 at the Association of EISEIKAI Medical and Healthcare Corporation Minamitama Hospital. Patients diagnosed with COVID-19 and approximately 30 days after symptom onset were included as the positive group. The serum SARS-CoV-2 antibodies were analysed using seven immunochromatography kits. RESULTS: Twenty samples (Positive group: 10 patients, Negative group: 10 healthy medical workers) were included in this study. The median age of the patients was 44 years, and the median duration from symptom onset was 30.5 days in the positive group. The accuracy rates for IgM/IgG detection were: 90.0%/100% in Kit A; 50.0%/95.0% in Kit B; 55.0%/65.0% in Kit C; 60.0%/55.0% in Kit D; 50.0%/80.0% in Kit E; 80.0%/90.0% in Kit F; and 90.0%/100% in Kit G. CONCLUSIONS: Our study showed that there is a variation of accuracy rates between immunochromatography kits for antibodies of SARS-CoV-2. COVID-19 IgG/IgM RAPID TEST CASSETTE (Hangzhou Biotest Biotech Co., Ltd., China) and Nadal COVID-19 IgG/IgM Rapid Test (BioServUK Ltd., UK: United Kingdom) have high accuracy rates for both IgM and IgG detection. Evidence from large population studies of immunochromatography kits is needed to clarify the details of diagnostic value for SARS-CoV-2.

The Effects of Safinamide Adjunct Therapy on Depression and Apathy in Patients With Parkinson's Disease: Post-hoc Analysis of a Japanese Phase 2/3 Study.

BACKGROUND AND PURPOSE: Neuropsychiatric symptoms in Parkinson's disease (PD) have been shown to significantly affect quality of life (QOL). We investigated the impact of safinamide on depression and apathy when administered as an adjunct to levodopa in Japanese patients with PD. METHODS: This was a post-hoc analysis of data from a phase 2/3 clinical study of safinamide in Japanese patients with PD experiencing wearing-off (JapicCTI-153056; https://www.clinicaltrials.jp/cti-user/trial/ShowDirect.jsp?japicId=JapicCTI-153056). Patients received placebo, safinamide 50 mg, or safinamide 100 mg as an adjunct therapy. The endpoints for this analysis were changes from baseline to Week 24 in the Unified Parkinson's Disease Rating Scale (UPDRS) Part I item 3 (depression) and item 4 (apathy) scores and the Parkinson's Disease Questionnaire (PDQ-39) "emotional well-being" domain score. Subgroup analyses investigated the relationship between neuropsychologic symptoms and improvements in motor fluctuation and assessed which patient populations might be expected to obtain neuropsychologic benefit from safinamide. RESULTS: Compared with placebo, safinamide (both doses) significantly improved UPDRS Part I item 3 scores in the overall analysis population, and the 100-mg dose improved UPDRS Part I item 4 scores in the population with apathy at baseline. Changes in the PDQ-39 "emotional well-being" score showed numerical, but not significant, dose-related improvements. Notable reductions in depression were associated with a change in daily ON-time ≥1 h, pain during OFF-time at baseline, and female sex. CONCLUSIONS: The results from this post-hoc analysis of the Japanese phase 2/3 study suggest that safinamide could bring benefits to patients with PD who have mild depression, pain during the OFF phase. In addition, safinamide might provide particular benefits for patients with PD who have mild apathy and female.

[Method Verification for Vitamin D Analysis in Processed Foods Based on the Analytical Manual for the Standard Tables of Food Composition in Japan 2015 (Seventh Revised Edition)].

Considerable amounts of processed foods contain vitamin D (ergocalciferol (D2) and cholecalciferol (D3)) as food additives. For field surveys on food additives, the analytical method for vitamin D should be well-validated. However, the current official method in Japan cannot separately determine the concentrations of D2 and D3, whereas the method for the Standard Tables of Food Composition in Japan 2015 (STFC method) can. Therefore, in this study, we verified the applicability of the STFC method to processed foods. During the course of this research, we added some improvements to the original method. Spike and recovery experiments using vegetable juice, soymilk, and corn flakes as food matrices showed that the recovery rates (relative standard deviation) of D2 and D3 were 103-112% (4.7-12.6%) and 102-109% (2.4-21.8%), respectively, at the estimated method limit of quantification (EMLOQ) level; and 100-110% (4.0-7.4%) and 102-105% (3.8-4.8%), respectively, at 10 times the EMLOQ level. These results indicated that accuracy and precision of the modified STFC method were enough to determine dietary D2 and D3 as endogenous nutrients and/or food additives, and suggested that this method is appropriate for analyzing vitamin D concentrations in processed foods.

[Proficiency Testing Schemes for Food Nutrition Analysis in Japan (2017-2018)].

This paper deals with proficiency testing schemes for food nutrition analysis in Japan. In schemes in 2017 and 2018, 65 and 73 organizations participated, respectively, and more than 70% of the participants were public organizations responsible for a nutrition-labeling compliance test. The food matrices were pork and chicken sausages, and analytes were protein, fat, ash, moisture, carbohydrate, energy, sodium, salt equivalent, calcium (2018 only), and iron (2018 only). The organizations reporting inadequate laboratory values in one or more nutrients for mandatory declaration (energy, protein, fat, carbohydrate, or salt equivalent) were 11 and 15% of all organizations and 9 and 13% of public organizations in the 2017 and 2018 schemes, respectively. The approximate relative standard deviations for proficiency assessment (RSDr) were as follows: protein, 2%; fat, 3%; ash, 2%; moisture, 0.5%; carbohydrate, 9%; energy, 1%; sodium (salt equivalent), 4%; calcium, 7%; and iron, 7%. Notably, the large RSDr value for carbohydrate may cause inconsistency among laboratories in compliance tests for foods containing several grams or less of carbohydrate per 100 grams.

Tandem Cation/Anion Exchange SPE Cartridge Method for Sample Desalting for HPLC Analysis of Soluble Dietary Fiber: Development and Inter-laboratory Validation.

In HPLC analyses of soluble dietary fiber, desalting processes using open, mixed-bed ion-exchange columns are time-consuming and labor-intensive. We developed and validated a simple desalting method using tandem cation/anion exchange SPE cartridges. We found that combining Bond Elut Jr SCX (upstream) and Bond Elut PSA (downstream) cartridges provided adequate desalting of test solutions. The developed method was then validated in an inter-laboratory study. Five test samples were prepared by mixing food matrixes with purified soluble dietary fiber and treated to generate solutions to test the desalting process. These solutions were then analyzed by eight different laboratories. The results demonstrated that the developed method is simple and reliable for desalting samples containing 140 to 945 mg/100 mL of soluble dietary fiber in preparation for HPLC analysis of soluble dietary fiber.