[Epidemiological study of occupational diseases in Shenzhen City, China in 2006~2017]

Objective: To study the epidemiological characteristics of occupational diseases in Shenzhen City, China in 2006-2017, and to provide a scientific basis for prevention and control of occupational diseases. Methods: Cases of occupational diseases in 2006-2017 were collected from the Information System of Occupational Diseases and Occupational Health. A statistical analysis was performed to identify the characteristics of the disease distribution in terms of spectrum of disease, year, area, industry, type of economy and enterprise scale. Results: A total of 1673 cases of occupational disease (64 types, 8 classes) were diagnosed and reported in 2006-2017, chemical poisoning (31.50%) , ear, nose and throat diseases (28.21%) , and pneumoconiosis and other respiratory diseases (21.34%) were the most three commonest occupational diseases. The constituent of ratio of ear, nose and throat diseases and occupational diseases caused by physical factors increased in turn, the constituent of chemical poisoning, pneumoconiosis and other respiratory diseases, and skin disease reduced in turn, which all showed the difference was statistically significant (P<0.01) . Occupational diseases were often seen in districts of Baoan, Longgang, Longhua and Pingshan, as well as in private economy and small enterprise, mainly occurred in manufacturing industry. Conclusion: The incidence of occupational diseases increased steadily in 2006-2017, and we need to strengthen common occupational diseases, especially occupational noise-induced hearing loss, pay attention to districts of Baoan, Longgang, Longhua and Pingshan, as well as private economy and small enterprise.

[Effect of imatinib on the height of children with chronic myeloid leukemia in the chronic phase]

目的

评估伊马替尼对慢性髓性白血病慢性期（CML-CP）儿童身高的影响。

方法

2018年7月至2019年7月，在全国范围内对诊断时年龄<18周岁、接受伊马替尼治疗至少3个月的CML儿童或其家长发放问卷，调查受访者伊马替尼治疗前后身高的变化。主要评价指标为身高标准差积分值（HtSDS）以及标准差积分的差值（ΔHtSDS），并分析其相关影响因素。

结果

共有238例受访者符合标准并被纳入研究，男性138例（58.0％），初诊时中位年龄11.0（1.4～17.9）岁，青春期前93例（39.0％），至填写答卷时，中位年龄15.0（2.0～34.0）岁，中位伊马替尼服药时间28（3～213）个月。受访者填写答卷时HtSDS（−0.063±1.361）较治疗前HtSDS（0.391±1.244）显著下降（P<0.001），71.0％的患儿出现身高增长减慢。青春期前服药者治疗后HtSDS下降显著（P<0.05），而青春期开始后服药者HtSDS变化不明显（P>0.05）。多因素分析显示，服药初始年龄较小（偏回归系数为0.122，B＝0.572，t＝10.733，P<0.001）和服药时间较长（偏回归系数为−0.006，B＝−0.211，t＝−4.062，P<0.001）是伊马替尼抑制身高增长的独立影响因素。

结论

伊马替尼引起CML-CP儿童身高增长障碍，服药初始年龄越小、服药时间越长，伊马替尼对身高的影响越明显。

Efficient radiation releasing in device-level glass ceramics driven by a blue laser

Ce³⁺ doped M₃Al₅O₁₂ (MAG, M=Lu, Y) glass ceramics (GCs) have been proved to be shapeable phosphors for white lighting driven by a 453 nm laser. Quantitative characterization reflects that the net emission powers of 4 wt% LuAG-doped GC and 4 wt% YAG-doped GC are 59.99 mW and 66.22 mW at the pump power of 117.63 mW, and the quantum yields reach up to 71.1% and 78.0%, respectively. Miniaturization of devices can be achieved for LuAG/YAG-GCs by optimizing sample size and phosphor concentration with maintaining fluorescence intensity of the samples. Presupposed color coordinate trace reveals that the high-brightness white fluorescence can be realized when the appropriate intensity ratio is determined between residual laser and sample emission. The tunable white fluorescence and the efficient radiation releasing illustrate that LuAG/YAG-GCs are potential candidates for application in solid-state laser illumination.

Non-trivial avalanches triggered by shear banding in compression of metallic glass foams

Ductile metallic glass foams (DMGFs) are a new type of structural material with a perfect combination of high strength and toughness. Owing to their disordered atomic-scale microstructures and randomly distributed macroscopic voids, the compressive deformation of DMGFs proceeds through multiple nanoscale shear bands accompanied by local fracture of cellular structures, which induces avalanche-like intermittences in stress–strain curves. In this paper, we present a statistical analysis, including distributions of avalanche size, energy dissipation, waiting times and aftershock sequence, on such a complex dynamic process, which is dominated by shear banding. After eliminating the influence of structural disorder, we demonstrate that, in contrast to the mean-field results of their brittle counterparts, scaling laws in DMGFs are characterized by different exponents. It is shown that the occurrence of non-trivial scaling behaviours is attributed to the localized plastic yielding, which effectively prevents the system from building up a long-range correlation. This accounts for the high structural stability and energy absorption performance of DMGFs. Furthermore, our results suggest that such shear banding dynamics introduce an additional characteristic time scale, which leads to a universal gamma distribution of waiting times.

Photon quantification in Ho3+/Yb3+ co-doped opto-thermal sensitive fluotellurite glass phosphor

Multi-photon-excited thermal-correlated green and red upconversion (UC) emissions have been quantified in Ho³⁺/Yb³⁺ co-doped fluotellurite (BZLFT) glass phosphor under the 978 nm laser excitation. The temperature dependence of the fluorescence intensity ratio (FIR) originated from UC emissions bands centered at 550 nm and 661 nm has been verified in the range of 303-543 K. The net emission photon numbers of ⁵F₄+⁵S₂→⁵I₈ and ⁵F₅→⁵I₈ transition emissions are up to 40.08×10¹² and 68.51×10¹²cps in the 0.4wt.%Ho₂O₃-0.4wt.%Yb₂O₃ co-doped BZLFT case under the 6.95W/mm² laser power density. Furthermore, the quantum yield (QY) and luminous flux are determined to be dependent on pumping power. When the excitation power increases 874 mW, the QY values for 550 nm and 661 nm emissions are as high as 0.94×10^-5 and 1.60×10^-5. In addition, the high photon producing efficiency is conducive to ensuring high feedback to thermosensitive performance. The temperature thermal sensor can be manipulated steadily in medium temperature range, and the relative sensitivity reaches 0.4%K^-1 at 303 K, which is 1 order of magnitude larger than those in several rare-earth-doped materials. Efficient photon conversion ability and high temperature sensitivity indicate that the rare-earth-ion-doped fluotellurite material has a prospective application in the construction of optical temperature sensors based on the FIR technique allowing for self-referenced temperature determination.

Association of genetic and environmental factors with dental caries among adolescents in south China: A cross-sectional study

AIM

The objective of this study was to investigative genetic and environmental factors that contribute to caries susceptibility among adolescents in south China.

MATERIALS AND METHODS

A cross-sectional study was conducted among 1055 adolescents aged 13-14 years old in south China. The International Caries Detection and Assessment System (ICDAS) was used to identify caries. Environmental variables were analysed by regression models. Twenty-three single nucleotide polymorphisms (SNPs) in 14 genes were identified from saliva samples. Regression analysis was used for the evaluation of effects of SNP markers using the minor allele as the effect allele.

RESULTS

Our results suggest that gender, Cariostat score and Plaque Index were associated with dental caries. After the adjustment by age and gender, the G allele in AMBN (rs13115627) nominally was a protective factor for caries under additive model (P=0.028; OR=0.782; 95% CI, 0.627-0.974). However, the association did not meet the Bonferroni correction significance cut-off for multiple testing.

CONCLUSION

Gender, Cariostat score and Plaque Index were associated with dental caries in this population. No selected SNPs showed a significant association with dental caries under either additive model or dominance model.

0637 Comparison of AHI and ESS Outcomes Between Patients with Obstructive Sleep Apnea Undergoing Sleep Surgery versus Upper Airway Stimulation

Introduction

Single or multi-level soft tissue surgical interventions are common options for CPAP-intolerant patients with OSA. Upper Airway Stimulation (UAS) is an alternative option using an implantable hypoglossal nerve stimulator. We compared patient outcomes between traditional sleep surgery (TSS) and UAS.

Methods

We selected patients who underwent TSS (including palate, oropharynx, tongue, and/or epiglottis-based procedures) for OSA and also met general UAS criteria (BMI≤35, AHI between 15-65, absence of palate concentric collapse during DISE, if available) for chart review. UAS outcomes were collected from the ADHERE international registry. For both groups, post-op AHI was collected, including full-night UAS efficacy studies. Data are presented as mean and standard deviation.

Results

The TSS group (n=284) and UAS group (n=541) were predominantly male and overweight. The TSS group was younger than UAS (47±12 vs 60±11 years, p&lt;0.001). At baseline, both groups had severe OSA with AHI of 34±14 and 36±15 (p=0.23) and excessive daytime sleepiness with ESS of 12±5 and 12±6, (p=0.38), respectively. TSS follow-up was 169±151 days vs 392±181 days for UAS, which was significantly different. UAS had significantly larger decrease in AHI than TSS (-21/h±18 vs -16/h±16, p&lt;0.0001). Both groups had a large decrease in ESS, however, the UAS group had a slightly smaller decrease, (-6±5 vs -5±5, p=0.01). Using the Sher response criteria of 50% AHI reduction and ≤ 20 events/hour, UAS had a 70% response rate vs 51% for TSS.

Conclusion

This study represents largest and first international, multicenter comparison of UAS to traditional surgical interventions for OSA, albeit with limitations of potential differential patient selection. While both TSS and UAS show similar improvement in symptoms, upper airway stimulation has a larger reduction of AHI with higher rates of therapy response than traditional sleep surgery

Support

ADHERE data assistance from Inspire Medical (Minneapolis, MN)

[Research progress in surface bonding pretreatment of dental zirconia ceramics]

Yttria stabilized tetragonal zirconia polycrystal ceramics is widely used in the field of dentistry because of its excellent mechanical properties and biocompatibility. However, it has low hydroxyl content and does not contain silica. Therefore micro mechanical retention induced by hydrofluoric acid etching on its surface is not applicable. The bonding of zirconia is a difficult problem. Zirconia surface pretreatment is commonly used to improve bonding strength and durability. This review summarizes surface pretreatment of dental zirconia ceramic including air abrasion, laser etching, acid etching, silica coating, non-thermal plasmas treatment, et al. In addition, it presents advantages and disadvantages of each treatment, provides guidance for application and future research directions.

Comparison of multimedia and printed patient education tools for patients with osteoporosis: a 6-month randomized controlled trial

We conducted a randomized controlled trial to compare the efficacy of adding a video tool to a printed booklet on osteoporosis. Both strategies were effective in increasing knowledge and decreasing decisional conflict. There was no difference in the measured outcomes between the intervention and control groups. Patient preferences and learning styles are key factors in deciding a presentation format when educating patients with osteoporosis.

INTRODUCTION

Innovative approaches to patient education about self-management in osteoporosis may improve outcomes.

METHODS

We conducted a randomized controlled trial to compare the efficacy of adding a multimedia patient education tool involving video modeling to a printed educational booklet on osteoporosis. Participants were post-menopausal women with osteoporosis. We assessed osteoporosis knowledge, decisional conflict, self-efficacy, and effectiveness in disease management at baseline, immediately post-intervention, and at 3 and 6 months. Linear regression models were used to explore changes in outcomes at 6 months with respect to baseline characteristics.

RESULTS

Two hundred and twenty-five women were randomized, 111 to receive the multimedia tool in addition to the booklet and 114 to receive the booklet alone. Knowledge and decisional conflict scores significantly improved in both groups at all post-intervention assessment points, but with no significant differences in score changes between the groups. Self-efficacy and disease management effectiveness showed no significant changes from baseline. In the entire cohort, younger age was associated with better effectiveness in disease management and Hispanic women had greater gains in knowledge at 6 months compared to White women. Women with limited health literacy who had received the multimedia tool in addition to the printed materials had higher decisional conflict than those who received printed materials alone.

CONCLUSION

Both multimedia and printed tools increased knowledge and decreased decisional conflict to the same extent, neither of the educational materials proved to be better than the other. For women with limited health literacy, receiving the booklet alone was more effective in reducing decisional conflict after 6 months, than adding the multimedia tool.

LncRNA NEAT1 regulated cell proliferation, invasion, migration and apoptosis by targeting has-miR-376b-3p/SULF1 axis in non-small cell lung cancer

OBJECTIVE

Recently, lncRNA has been determined to play an important role in cancer formation and development. However, the regulatory mechanism of lncRNA in NSCLC has not been fully explored.

PATIENTS AND METHODS

The expression of NEAT1, miR-376b-3p, and SULF1 was detected in each group via quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The proteins expression of SULF1, p-MAPK, MAPK, p-Akt, Akt, and GAPDH were measured via Western blot. MTT assay was applied to detect cell proliferation in each group. Transwell assay was used to assess cell invasion and migration of each group. Cell apoptosis was assessed with flow cytometry. The relationship among NEAT1, miR-376b-3p, and SULF1 was determined using Luciferase reporter assay.

RESULTS

In this study, the expression of NEAT1 and SULF1 was upregulated in NSCLC tissues and cells. Of note, the knockdown of NEAT1 and SULF1 could inhibit cell proliferation, migration, and invasion and promote cell apoptosis in NSCLC. Moreover, NEAT1 regulated SULF1 expression via binding to miR-376b-3p in NSCLC cells. Otherwise, the effects of NEAT1 on cell growth and apoptosis were reversed by improving the SULF1 expression in NSCLC cells. Meanwhile, si-NEAT1 transfection inhibited MAPK and Akt signaling pathway by modulating SULF1 in NSCLC cells.

CONCLUSIONS

In this study, we found that lncRNA NEAT1 regulated cell proliferation, invasion, migration, and apoptosis by targeting has-miR-376b-3p/SULF1 axis in NSCLC. Moreover, the regulatory network of NEAT1 participated in the phosphorylation levels of MAPK and Akt to affect cell progression of NSCLC, providing a new regulatory pathway in the pathogenesis of lung cancer.

Sex modulates the apolipoprotein E ε4 effect on white matter and cortical functional connectivity in individuals with amnestic mild cognitive impairment

BACKGROUND AND PURPOSE

Recent studies from the Alzheimer's Disease Neuroimaging Initiative show that, in the USA, 75% of patients with Alzheimer's disease are female. To date, there have rarely been any attempts to analyze data by sex or gender, which limits the potential for discovering the effects of sex or gender on disease. Little evidence is available regarding the effect of gender and apolipoprotein E (APOE) ε4 on white matter (WM) connection from the functional perspective due to the lack of appropriate techniques for detecting blood-oxygen-level-dependent signals in WM.

METHODS

We took advantage of a new framework known as functional tensor imaging to investigate the effect of sex and APOEε4 on WM cortical functional connectivity throughout the brain.

RESULTS

In a group of female patients with amnestic mild cognitive impairment, we found a significantly reduced functional connectivity in the left posterior limb of the internal capsule, left superior fronto-occipital fasciculus, bilateral temporopolar area and right somatosensory association cortex in APOEε4 carriers in contrast to non-carriers. We also found a significant APOEε4 by sex interaction effect on the right somatosensory association cortex, left temporopolar area and left superior temporal gyrus. The clinical Montreal Cognitive Assessment score was significantly negatively associated with the right somatosensory association cortex with APOEε4 by sex interaction in males.

CONCLUSIONS

These results indicate that increased APOE-related risk in women may be associated with decreased activity in both gray matter and WM in patients with amnestic mild cognitive impairment compared with men. The finding suggests accounting for sex differences in neuroimaging biomarkers, diagnostics and treatment strategy.

HIV infection and electrocardiogram abnormalities: baseline assessment from the CHART cohort

OBJECTIVES

To investigate the prevalence of various electrocardiogram (ECG) abnormalities among HIV-positive and HIV-negative individuals.

METHODS

This cross-sectional evaluation included 1412 HIV-positive and 2824 HIV-negative participants aged 18 to 75 years and frequency matched by age and sex, derived from the baseline survey of Comparative HIV and Aging Research in Taizhou (CHART), China, between February and December 2017.

RESULTS

HIV-positive individuals had higher prevalence of sinus tachycardia (5.6% (79/1412) vs. 1.3% (36/2824), p < 0.001) and ST/T wave abnormalities (14.9% (211/1412) vs. 9.4% (264/1412), p < 0.001) but lower prevalence of sinus bradycardia (4.8% (68/1412) vs. 7.5% (211/2824), p 0.001); such associations remained statistically significant after adjusting for traditional risk factors (respectively, adjusted odds ratio (aOR) 4.68, 95% confidence interval (CI) 3.06-7.17; aOR 1.89, 95% CI 1.54-2.34; aOR 0.60, 95% CI 0.44-0.80). In adjusted models, being in higher carotid intima-media thickness categories was significantly associated with ST/T abnormalities in HIV-positive individuals only (0.78-1.00 mm: aOR 1.46, 95% CI 1.01-2.12; >1.00 mm: aOR 2.18, 95% CI 1.39-3.42), whereas being in higher blood pressure categories was significantly associated with both sinus tachycardia (prehypertension: aOR 5.61, 95% CI 1.76-17.91; hypertension: aOR 12.62, 95% CI 3.60-44.27) and ST/T abnormalities (hypertension: aOR 2.04, 95% CI 1.41-2.95) in HIV-negative individuals only. Longer duration of known HIV infection was the only HIV-specific factor of ST/T abnormalities (aOR 1.61, 95% CI 1.17-2.22), with none for sinus tachycardia.

CONCLUSIONS

HIV infection is independently associated with sinus tachycardia and ST/T abnormalities. Further research is needed to investigate specific mechanisms by which HIV infection leads to ECG abnormalities and to evaluate whether inclusion of ECG parameters improves cardiovascular disease prediction. Integrating ECG screening into routine HIV care is recommended in China.

Brassinosteroids are involved in ethylene-induced Pst DC3000 resistance in Nicotiana benthamiana

Plant immunity is regulated by a huge phytohormone regulation network. Ethylene(ET) and brassinosteroids (BRs) play critical roles in plant response to biotic stress; however, the relationship between BR and ET in plant immunity is unclear. We used chemical treatments, genetic approaches and inoculation experiments to investigate the relationship between ET and BR in plant defense against Pst DC3000 in Nicotiana benthamiana. Foliar applications of ET and BR enhanced plant resistance to Pst DC3000 inoculation, while treatment with brassinazole (BRZ, a specific BR biosynthesis inhibitor) eliminated the ET induced plant resistance to Pst DC3000. Silencing of DWARF 4(DWF4, a key BR biosynthetic gene), BRASSINOSTEROID INSENSITIVE 1 (BRI1, aBR receptor) and BRASSINOSTEROID-SIGNALING KINASE 1 (BSK1, downstream of BRI1) also neutralised the ET-induced plant resistance to Pst DC3000. ET can induce callose deposition and reactive oxygen species (ROS) accumulation to resistPst DC3000, BRZ-treated and gene-silenced were completely eliminate this response. Our results suggest BR is involved in ET-induced plant resistance, the involvement of ET in plant resistance is possibly by the induction of callose deposition and ROS accumulation, in a BR-dependent manner.

The effect of reduced balanced protein diet on the behavior of female broiler breeders in 2 generations

The behavior of 2 generations of broiler breeders undergoing a 25% reduced balanced protein (RP) dietary treatment was investigated in the current study. There were 2 treatments for the F0 generation: control (C) breeders fed with standard C diets and RP breeders fed with RP diets. The female progeny of each treatment was again subjected to 2 dietary treatments, resulting in 4 treatments for F1 generation: C/C, C/RP, RP/C, and RP/RP (breeder feed in F0/F1 generation). To maintain the target body weights throughout the trial, breeders on RP diet received on average 10% more feed than C diet breeders. The behavior of the breeders at 8h30 (30 min before feeding at 9h00), 12h00, and 15h30 in weeks 23 and 37 of the F0 generation and in week 6, 11, and 22 of the F1 generation was observed. Litter scratching, feather pecking, and object pecking were occasionally increased by RP diet feeding which indicated feeding frustration. Drinking behavior decreased dramatically by the RP dietary feeding and resulting in a better litter condition which could benefit dust bathing behavior. In addition, feeding the breeders RP diet in the F0 generation decreased litter scratching (week 6) and feather pecking (week 22, 15h30) but increased sitting (week 11, 15h30) and drinking (a tendency in week 6 and a significant effect in week 11) behavior of offspring breeders (F1 generation). In general, breeders fed with reduced balanced protein diets, to some extent, spent less time drinking and their offspring could have an adaptation to the maternal RP diet. The mechanism of this adaptation still needs to be further investigated. In general, positive effects were found by reducing protein level of breeder diets. However, negative side effects such as feeding frustration were also observed, which merit further study.

[The 472nd case: dyspnea, pulmonary shadows, abnormalities of whole blood cells]

A 54-year-old man was admitted to respiratory department with chief complaints of recurrent cough and dyspnea. Chest imaging showed multiple patchy shadows and interstitial changes. Evidence of infectious diseases was not definite, and antibiotic treatments were not effective. In the meantime, myelodysplasia syndrome was diagnosed with pancytopenia. The pathologic findings of transbronchoscopic lung biopsyshowed chronic inflammatory interstitial changes, suggesting a clinical diagnosis of organizing pneumonia. After glucocorticoids treatment, his condition aggravated. The second percutaneous lung biopsy showed the infiltration of a large number of neutrophils. Therefore, the final diagnosis of myelodysplasia syndrome with Sweet syndrome was made. Then glucocorticoids and supportive treatment were given This case may improve physicians' understanding of myelodysplasia syndrome complicated with Sweet syndrome.

Paclitaxel inhibits the progression of cervical cancer by inhibiting autophagy via lncRNARP11-381N20.2

OBJECTIVE

To observe the effect of paclitaxel on the autophagy of human cervical cancer cell lines by the expression regulation of lncRNARP11-381N20.2 as well as to explore the interaction and relationship between autophagy, proliferation, and apoptosis of cervical cancer cells.

MATERIALS AND METHODS

Genome-wide expression profiles of tumors and their susceptibility to drugs were downloaded through TCGA database to find differentially expressed lncRNA RP11-381N20.2 in chemosensitive sensitive and insensitive groups. Expression of RP11-381N20.2 in 60 cervical cancer tissues and 30 normal tissues was detected by qRT-PCR. The relationship between the expression of RP11-381N20.2 and the clinicopathological parameters of lung cancer was statistically analyzed. The recombinant plasmid pcDNA-RP11-381N20.2 and pcDNA-NC of RP11-381N20.2 were transfected into SiHa cells by lipofectamine, respectively. The autophagy and phenotypic effects were observed. Cell proliferation was determined by colony formation assay. Apoptosis was detected by flow cytometry. Western blot was conducted to detect expressions of autophagy-related proteins.

RESULTS

Genome-wide expression profiles of chemotherapy-sensitive and insensitive data in patients with cervical cancer in TCGA database were analyzed by edger package, results showed that the expression of lncRNA RP11-381N20.2 was significantly lower in the chemotherapy-insensitive group. qRT-PCR results showed that the expression of RP11-381N20.2 in cervical cancer was decreased, and the total survival time of patients was positively correlated with the expression of RP11-381N20.2. RP11-381N20.2 was associated with TNM (tumor node metastasis) staging and tumor size. Biological functions of SiHa cells showed that the expression of RP11-381N20.2 was negatively correlated with the treatment time and dose of paclitaxel. Colony formation assay showed that paclitaxel could inhibit the proliferation of cervical cancer cells in a dose-dependent manner. Flow cytometry showed that paclitaxel induced apoptosis of cervical cancer cells, which was more promoted after combination with RP11-381N20.2. Western blot results suggested that paclitaxel could induce autophagy in cervical cancer cells in a time- and dose-dependent manners. Paclitaxel combined with RP11-381N20.2 could significantly increase apoptosis of cervical cancer cells.

CONCLUSIONS

During the killing process of paclitaxel on cervical cancer SiHa cells, cell autophagy would affect the efficacy, after overexpression of RP11-381N20.2 in SiHa cells, autophagy induced by paclitaxel was inhibited, thereby enhancing the killing effect of paclitaxel on tumor cells.

Determination of Monensin, Narasin, and Salinomycin in Mineral Premixes, Supplements, and Animal Feeds by Liquid Chromatography and Post-Column Derivatization: Collaborative Study

A liquid chromatographic (LC) method for the analysis of monensin, narasin, and salinomycin in mineral premixes, supplements, and complete animal feeds at medicating and trace levels was collaboratively studied. The method uses methanolwater (90 + 10) extraction with mechanical shaking for 1 h, filtration, and dilution if necessary. Determination of the 3 ionophores is by reversed-phase LC using post-column derivatization with vanillin and detection at 520 nm. Suspect positive trace-level products and medicated feeds containing unexpected ionophores are confirmed by hexane extraction or post-column derivatization with dimethylaminobenzaldehyde (DMAB). Twenty-five test samples of medicated feeds, supplements, and mineral and drug premixes, and 9 test samples for trace-level analysis were sent to 11 collaborators in Bulgaria, Czech Republic, Portugal, France, The Netherlands, United States, and Canada. Acceptable results were received from 10 laboratories. For the medicated complete feeds, supplements, and mineral premixes, RSDr values (within-laboratory repeatability) ranged from 2.5 to 5.2%, RSDR values (among-laboratory reproducibility) ranged from 2.7 to 6.8%, and HorRat values ranged from 0.31 to 1.30. For the drug premixes, the result variability was excessive and HorRat values ranged from 2.27 to 14.1. For the trace-level test samples, all laboratories correctly identified the analytes and did not report any false positives. RSDr values ranged from 1.3 to 9.5%, RSDR values ranged from 5.2 to 13.1%, and HorRat values ranged from 0.4 to 0.97.