[Outcomes and care practices of extremely preterm infants at 22-25 weeks' gestation age from the Chinese Neonatal Network]

Objective: To describe the current status and trends in the outcomes and care practices of extremely preterm infants at 22-25 weeks' gestation age from the Chinese Neonatal Network (CHNN) from 2019 to 2021. Methods: This cross-sectional study used data from the CHNN cohort of very preterm infants. All 963 extremely preterm infants with gestational age between 22-25 weeks who were admitted to neonatal intensive care units (NICU) of the CHNN from 2019 to 2021 were included. Infants admitted after 24 hours of life or transferred to non-CHNN hospitals were excluded. Perinatal care practices, survival rates, incidences of major morbidities, and NICU treatments were described according to different gestational age groups and admission years. Comparison among gestational age groups was conducted using χ2 and Kruskal-Wallis tests. Trends by year were evaluated by Cochran-Armitage and Jonckheere-Terpstra tests for trend. Results: Of the 963 extremely preterm infants enrolled, 588 extremely preterm infants (61.1%) were male. The gestational age was 25.0 (24.4, 25.6) weeks, with 29 extremely preterm infants (3.0%), 88 extremely preterm infants (9.1%), 264 extremely preterm infants (27.4%), and 582 extremely preterm infants (60.4%) at 22, 23, 24, and 25 weeks of gestation age, respectively. The birth weight was 770 (680, 840) g. From 2019 to 2021, the number of extremely preterm infants increased each year (285, 312, and 366 extremely preterm infants, respectively). Antenatal steroids and magnesium sulfate were administered to 67.7% (615/908) and 51.1% (453/886) mothers of extremely preterm infants. In the delivery room, 20.8% (200/963) and 69.5% (669/963) extremely preterm infants received noninvasive positive end-expiratory pressure support and endotracheal intubation. Delayed cord clamping and cord milking were performed in 19.0% (149/784) and 30.4% (241/794) extremely preterm infants. From 2019 to 2021, there were significant increases in the usage of antenatal steroids, antenatal magnesium sulfate, and delivery room noninvasive positive-end expiratory pressure support (all P<0.05). Overall, 349 extremely preterm infants (36.2%) did not receive complete care, 392 extremely preterm infants (40.7%) received complete care and survived to discharge, and 222 extremely preterm infants (23.1%) received complete care but died in hospital. The survival rates for extremely preterm infants at 22, 23, 24 and 25 weeks of gestation age were 10.3% (3/29), 23.9% (21/88), 33.0% (87/264) and 48.3% (281/582), respectively. From 2019 to 2021, there were no statistically significant trends in complete care, survival, and mortality rates (all P>0.05). Only 11.5% (45/392) extremely preterm infants survived without major morbidities. Moderate to severe bronchopulmonary dysplasia (67.3% (264/392)) and severe retinopathy of prematurity (61.5% (241/392)) were the most common morbidities among survivors. The incidences of severe intraventricular hemorrhage or periventricular leukomalacia, necrotizing enterocolitis, and sepsis were 15.3% (60/392), 5.9% (23/392) and 19.1% (75/392), respectively. Overall, 83.7% (328/392) survivors received invasive ventilation during hospitalization, with a duration of 22 (10, 42) days. The hospital stay for survivors was 97 (86, 116) days. Conclusions: With the increasing number of extremely preterm infants at 22-25 weeks' gestation admitted to CHNN NICU, the survival rate remained low, especially the rate of survival without major morbidities. Further quality improvement initiatives are needed to facilitate the implementation of evidence-based care practices.

High glucose enhances the activation of NLRP3 inflammasome by ambient fine particulate matter in alveolar macrophages

BACKGROUND

Epidemiological studies have demonstrated that individuals with preexisting conditions, including diabetes mellitus (DM), are more susceptible to air pollution. However, the underlying mechanisms remain unclear. In this study, we proposed that a high glucose setting enhances ambient fine particulate matter (PM2.5)-induced macrophage activation and secretion of the proinflammatory cytokine, IL-1β, through activation of the NLRP3 inflammasome, altering the balance between matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs).

RESULTS

Exposure of mouse alveolar macrophages to non-cytotoxic doses of PM2.5 led to upregulation of IL-1β, activation of the NLRP3 inflammasome, increased nuclear translocation of the transcription factor NF-κB, increased generation of reactive oxygen species (ROS), and increased expression and enzymatic activity of MMP-9; these effects were enhanced when cells were pretreated with high glucose. However, pretreatment in a high glucose setting alone did not induce significant changes. ROS generation following PM2.5 exposure was abolished when cells were pretreated with ROS scavengers such as Trolox and superoxide dismutase (SOD), or with an NADPH oxidase inhibitor, DPI. Pretreatment of cells with DPI attenuated the effects of a high glucose setting on PM2.5-induced upregulation of IL-1β, activation of the NLRP3 inflammasome, and nuclear translocation of NF-κB. In addition, enhancement of PM2.5-induced expression and enzymatic activity of MMP-9 following high glucose pretreatment was not observed in primary alveolar macrophages obtained from NLRP3 or IL-1R1 knockout (KO) mice, where pro-IL-1β cannot be cleaved to IL-1β or cells are insensitive to IL-1β, respectively.

CONCLUSIONS

This study demonstrated that exposure of mouse alveolar macrophages to PM2.5 in a high glucose setting enhanced PM2.5-induced production of IL-1β through activation of the NLRP3 inflammasome and nuclear translocation of NF-κB due to PM2.5-induced oxidative stress, leading to MMP-9 upregulation. The key role of NADPH oxidase in PM2.5-induced ROS generation and activation of the IL-1β secretion pathway and the importance of IL-1β secretion and signaling in PM2.5-induced increases in MMP-9 enzymatic activity were also demonstrated. This study provides a further understanding of the potential mechanisms underlying the susceptibility of individuals with DM to air pollution and suggests potential therapeutic targets.

[Summary of the 14th Asia Pacific Burn Congress, the 18th Chinese Symposium on Burn Medicine, and the 2023 Huaxia Burn Forum]

The 14th Asia Pacific Burn Congress, the 18th Chinese Symposium on Burn Medicine, and the 2023 Huaxia Burn Forum was held successfully in Chongqing from September 13th to 16th, 2023. More than 1 000 participants from more than 10 countries and regions attended the congress, including over 100 overseas experts. The theme of the congress was homage, heritage, and innovation, and three-day academic exchange was held in the form of academician forum, keynote forum, and seven thematic sub-forums focused on the hot spots and difficulties in the fields of burns, trauma, wound repair, and related fields. The congress was compact, comprehensive, in-depth, and fruitful, with warm atmosphere at the meeting site.

Single-Cell RNA Sequencing Reveals a Subset of cMAS can Aggravate RIHD through CXCL1-CXCR2 Axis

PURPOSE/OBJECTIVE(S)

Radiation induced heart disease (RIHD) is any form of cardiac toxicity induced by radiation therapy (RT) for thoracic cancers. Our previous studies have shown that RT obviously contributed to cardiovascular diseases-specific death over 3 years while RT became protective in the short term within 2 years survival in non-small cell lung cancer patients. Here, single cell RNA sequencing (scRNA-seq) was performed to identify various cell subsets and investigate their functions and dynamics in RIHD which offered several targets for early clinical interventions to alleviate RIHD.

MATERIALS/METHODS

Based on evaluation of histopathological characteristics, ejection fraction and serum levels of cardiac injury biomarkers, we have established mouse models during different stages to simulate clinical RIHD progression. Hence, we performed single cell RNA-sequencing of RIHD models to characterize the diversity within specific cell types and obtain basic information of differently expressed genes (DEGs). We investigated the role of several cell clusters and DEGs in RIHD through bioinformatics analysis and experimental verification. In vivo, mouse models were given intraperitoneal injection of CXCR2 inhibitor. Bone marrow macrophages and primary cardiac fibroblasts were extracted for in vitro experiments.

RESULTS

RIHD processes were divided into acute injury, compensation and decompensation stage. Transcriptomes of 31769 single cells from cardiac suspension have been profiled. Analysis of scRNA-seq revealed that there were 30 cell clusters participating in RIHD. The fraction of cell populations varied greatly at three stages which indicated RIHD was a dynamic process and each cell cluster functioned differently at different stages. Notably, we observed cardiac resident macrophages (cMAS) subset accounted for the highest fraction during the compensatory period and decreased in decompensation period. Pseudotime analysis showed cMAS had a different developmental trajectory compared to myeloid derived cells. Moreover, CXCR2 was significantly expressed in cMAS cluster. Ligand-receptor interaction results suggested that CXCL1 secreted by cardiac fibroblasts bind primarily to CXCR2+ cMAS and participated in the formation of the extracellular matrix (ECM) related to cardiac fibrosis. Moreover, cardiac fibrosis of RIHD models were relieved after CXCR2 inhibitor treatment. CXCL1 expression in primary cardiac fibroblast elevated after RT.

CONCLUSION

The identification of main cell clusters provided a new insight to investigate RIHD through dynamics of cell phenotypes and cell-cell communications during RIHD processes. In compensation stage, CXCR2+ cMAS could be activated by CXCL1 secreted by cardiac fibroblasts. Both were associated with ECM and contribute to the decompensation stage.

[Long-term outcomes of childhood steroid-sensitive nephrotic syndrome]

Objective: To investigate the long-term outcomes and risk factors in children with steroid-sensitive nephrotic syndrome (SSNS). Methods: A retrospective cohort study was conducted on newly onset SSNS admitted to the Department of Pediatrics of the First Affiliated Hospital of Sun Yat-sen University from January 2006 to December 2010 and 105 cases with follow-up for more than 10 years were included. Clinical data including general characteristics, clinical manifestation, laboratory tests, treatment and prognosis. The primary outcome was the clinical cure, and the secondary outcomes were relapse or ongoing immunosuppressive treatment within the last 1 year of follow-up and complications at the last follow-up. According to the primary outcome, the patients were divided into clinical cured group and uncured group. Categorical variables were compared between 2 groups using the χ² or Fisher exact test, and continuous variables by t or Mann-Whitney U test. Multiple Logistic regression models were used for multivariate analysis. Results: Of the 105 children with SSNS, the age of onset was 3.0 (2.1, 5.0) years, and 82 (78.1%) were boys, 23(21.9%) were girls. The follow-up time was (13.1±1.4) years; 38 patients (36.2%) had frequently relapsing or steroid-dependent nephrotic syndrome (FRNS or SDNS) and no death or progression to end-stage kidney disease. Eighty-eight patients (83.8%) were clinically cured. Seventeen patients (16.2%) did not reach the clinical cure criteria, and 14 patients (13.3%) had relapsed or ongoing immunosuppressive treatment within the last year of follow-up. The proportion of FRNS or SDNS (12/17 vs. 29.5% (26/88), χ²=10.39), the proportion of treatment with second-line immunosuppressive therapy (13/17 vs. 18.2% (16/88), χ²=21.39), and the level of apolipoprotein A1 at onset ((2.0±0.5) vs. (1.7±0.6) g/L, t=2.02) in the uncured group were higher than those in the clinical cured group (all P<0.05). Multivariate Logistic regression analysis showed that patients treated with immunosuppressive therapy had an increased risk of not reaching clinical cure in the long term (OR=14.63, 95%CI 4.21-50.78, P<0.001). Of the 55 clinically cured patients who had relapsed, 48 patients (87.3%) did not relapse after 12 years of age. The age at last follow-up was 16.4 (14.6, 18.9) years, and 34 patients (32.4%) were ≥18 years of age. Among the 34 patients who had reached adulthood, 5 patients (14.7%) still relapsed or ongoing immunosuppressive treatment within the last year of follow-up. At the last follow-up, among the 105 patients, 13 still had long-term complications, and 8 patients were FRNS or SDNS. The proportion of FRNS or SDNS patients with short stature, obesity, cataracts, and osteoporotic bone fracture was 10.5% (4/38), 7.9% (3/38), 5.3% (2/38), and 2.6% (1/38), respectively. Conclusions: The majority of SSNS children were clinically cured, indicating a favorable long-term prognosis. History of treatment with second-line immunosuppressive therapy was the independent risk factor for patients not reaching the clinical cure criteria in the long term. While it is not uncommon for children with SSNS to persist into adulthood. The prevention and control of long-term complications of FRNS or SDNS patients should be strengthened.

MMP-3-mediated cleavage of OPN is involved in copper oxide nanoparticle-induced activation of fibroblasts

BACKGROUND

Copper oxide nanoparticles (Nano-CuO) are one of the most produced and used nanomaterials. Previous studies have shown that exposure to Nano-CuO caused acute lung injury, inflammation, and fibrosis. However, the mechanisms underlying Nano-CuO-induced lung fibrosis are still unclear. Here, we hypothesized that exposure of human lung epithelial cells and macrophages to Nano-CuO would upregulate MMP-3, which cleaved osteopontin (OPN), resulting in fibroblast activation and lung fibrosis.

METHODS

A triple co-culture model was established to explore the mechanisms underlying Nano-CuO-induced fibroblast activation. Cytotoxicity of Nano-CuO on BEAS-2B, U937* macrophages, and MRC-5 fibroblasts were determined by alamarBlue and MTS assays. The expression or activity of MMP-3, OPN, and fibrosis-associated proteins was determined by Western blot or zymography assay. Migration of MRC-5 fibroblasts was evaluated by wound healing assay. MMP-3 siRNA and an RGD-containing peptide, GRGDSP, were used to explore the role of MMP-3 and cleaved OPN in fibroblast activation.

RESULTS

Exposure to non-cytotoxic doses of Nano-CuO (0.5 and 1 µg/mL) caused increased expression and activity of MMP-3 in the conditioned media of BEAS-2B and U937* cells, but not MRC-5 fibroblasts. Nano-CuO exposure also caused increased production of cleaved OPN fragments, which was abolished by MMP-3 siRNA transfection. Conditioned media from Nano-CuO-exposed BEAS-2B, U937*, or the co-culture of BEAS-2B and U937* caused activation of unexposed MRC-5 fibroblasts. However, direct exposure of MRC-5 fibroblasts to Nano-CuO did not induce their activation. In a triple co-culture system, exposure of BEAS-2B and U937* cells to Nano-CuO caused activation of unexposed MRC-5 fibroblasts, while transfection of MMP-3 siRNA in BEAS-2B and U937* cells significantly inhibited the activation and migration of MRC-5 fibroblasts. In addition, pretreatment with GRGDSP peptide inhibited Nano-CuO-induced activation and migration of MRC-5 fibroblasts in the triple co-culture system.

CONCLUSIONS

Our results demonstrated that Nano-CuO exposure caused increased production of MMP-3 from lung epithelial BEAS-2B cells and U937* macrophages, which cleaved OPN, resulting in the activation of lung fibroblasts MRC-5. These results suggest that MMP-3-cleaved OPN may play a key role in Nano-CuO-induced activation of lung fibroblasts. More investigations are needed to confirm whether these effects are due to the nanoparticles themselves and/or Cu ions.

Nickel nanoparticles induce autophagy and apoptosis via HIF-1α/mTOR signaling in human bronchial epithelial cells

With the rapid development of nanotechnology, the potential adverse health effects of nanoparticles have been caught more attention and become global concerns. However, the underlying mechanisms in metal nanoparticle-induced toxic effects are still largely obscure. In this study, we investigated whether exposure to nickel nanoparticles (Nano-Ni) and titanium dioxide nanoparticles (Nano-TiO₂) would alter autophagy and apoptosis levels in normal human bronchial epithelial BEAS-2B cells and the underlying mechanisms involved in this process. Our results showed that the expressions of autophagy- and apoptosis-associated proteins were dysregulated in cells exposed to Nano-Ni. However, exposure to the same doses of Nano-TiO₂ had no significant effects on these proteins. In addition, exposure to Nano-Ni, but not Nano-TiO₂, led to nuclear accumulation of HIF-1α and decreased phosphorylation of mTOR in BEAS-2B cells. Inhibition of HIF-1α by CAY10585 abolished Nano-Ni-induced decreased phosphorylation of mTOR, while activation of mTOR by MHY1485 did not affect Nano-Ni-induced nuclear accumulation of HIF-1α. Furthermore, both HIF-1α inhibition and mTOR activation abolished Nano-Ni-induced autophagy but enhanced Nano-Ni-induced apoptosis. Blockage of autophagic flux by Bafilomycin A1 exacerbated Nano-Ni-induced apoptosis, while activation of autophagy by Rapamycin effectively rescued Nano-Ni-induced apoptosis. In conclusion, our results demonstrated that Nano-Ni exposure caused increased levels of autophagy and apoptosis via the HIF-1α/mTOR signaling axis. Nano-Ni-induced autophagy has a protective role against Nano-Ni-induced apoptosis. These findings provide us with further insight into Nano-Ni-induced toxicity.

Prenatal benzo[a]pyrene exposure impairs hippocampal synaptic plasticity and cognitive function in SD rat offspring during adolescence and adulthood via HDAC2-mediated histone deacetylation

Benzo[a]pyrene (B[a]P) is a widespread carcinogenic pollutant in the environment. Although previous studies have demonstrated the neurodevelopmental toxicity of B[a]P, the precise mechanisms underlying the neurotoxic effects induced by prenatal B[a]P exposure remain largely unknown. In the present study, pregnant Sprague-Dawley (SD) rats were injected intraperitoneally with 0, 10, 20, or 40 mg/kg-bw of B[a]P for three consecutive days on embryonic days 17-19. The learning and memory abilities of offspring were determined by Morris Water Maze (MWM) test, while the number of dendritic branches and the density of dendritic spines in hippocampal CA1 and DG regions were evaluated by Golgi-Cox staining at PND 45 and PND 75. The mRNA expression of BDNF, PSD-95, and SYP in offspring hippocampus were detected by qRT-PCR, and the protein expression of BDNF, PSD-95, SYP, HDAC2, acH3K9, and acH3K14 were measured by Western blotting or immunohistochemistry. CHIP-PCR was performed to further detect the levels of acH3K9 and acH3K14 in the promoter regions of BDNF and PSD-95 genes. Our results showed that rats prenatally exposed to B[a]P exhibited impaired spatial learning and memory abilities and the number of dendritic branches and the density of dendritic spines in the hippocampal CA1 and DG regions were significantly reduced during adolescence and adulthood. The expression of HDAC2 protein was significantly upregulated, while acH3K9, acH3K14, BDNF, PSD-95, and SYP protein levels were significantly downregulated in the hippocampus of B[a]P- exposed rats. In addition, CHIP results showed that prenatal B[a]P exposure markedly decreased the level of acH3K9 and acH3K14 in the promoter region of BDNF and PSD-95 gene in the hippocampus of PND 45 and PND 75 offspring. All of the results suggest that prenatal B[a]P exposure impairs cognitive function and hippocampal synaptic plasticity of offspring in adolescence and adulthood, and HDAC2-mediated histone deacetylation plays a crucial role in these deficits.

[Progress in platelets and chronic obstructive pulmonary disease]

Platelets-related pathophysiological mechanism and clinical research is one of the research hot topics in chronic obstructive pulmonary disease (COPD) at home and abroad. Increasing evidence has proved the association between thrombocytosis and COPD. Platelets activation interacts with COPD. Antiplatelet therapy has been shown to have significant effects on both short-term and long-term outcomes in COPD. Platelets inhibition may be an emerging therapeutic target for COPD, and antiplatelet therapy is expected to become an inexpensive and effective treatment for COPD. This article reviewed the research progress in platelets and COPD.

[Summary of the 17th Chinese Symposium on Burn Medicine and the 2022 Congress of Burn Medicine Branch of China International Exchange and Promotion Association for Medical and Healthcare, and the 12th Academic Conference on Burn and Plastic Surgery in Five Provinces and One City in Southwest China]

The 17th Chinese Symposium on Burn Medicine and the 2022 Congress of Burn Medicine Branch of China International Exchange and Promotion Association for Medical and Healthcare, and the 12th Academic Conference on Burn and Plastic Surgery in Five Provinces and One City in Southwest China was successfully held in green city Nanning, from August 25th to 27th, 2022. The conference theme was "Burn treatment and wound repair", received nearly 200 submissions, nearly 1 100 online and offline registered delegates, and nearly 300 offline attendees. The meetings were held in one main venue and three branch venues, with combination of speaking offline and live and recorded broadcast, as well as whole process synchronous live broadcasting. During the meeting, key issues about burn treatment and wound repair were discussed, with warm academic atmosphere.

Transcriptome-wide association study identifies PSMB9 as a susceptibility gene for coal workers' pneumoconiosis

Coal workers' pneumoconiosis (CWP) is a type of typical occupational lung disease caused by prolonged inhalation of coal mine dust. The individuals' different genetic background may underlie their different susceptibility to develop pneumoconiosis, even under the same exposure level. This study aimed to identify susceptibility genes associated with CWP. Based on our previous genome-wide association study (GWAS, 202 CWP cases vs. 198 controls) and gene expression data obtained by analyzing human lungs and whole blood from the Genotype-Tissue Expression (GTEx) Portal, a transcriptome-wide association study (TWAS) was applied to identify CWP risk-related genes. Luciferase report gene assay, qRT-PCR, Western blot, immunofluorescence assay, and TUNEL assay were conducted to explore the potential role of the candidate gene in CWP. Proteasome 20S subunit beta 9 (PSMB9) was identified as a strong risk-related gene of CWP in both lungs and whole blood (Lungs: P_TWAS  = 4.22 × 10^-4 ; Whole blood: P_TWAS  = 2.11 × 10^-4 ). Single nucleotide polymorphisms (SNPs) rs2071480 and rs1351383, which locate in the promoter region and the first intron of the PSMB9 gene, were in high linkage disequilibrium (LD, r²  = 0.98) with the best GWAS SNP rs4713600 (G>T, OR = 0.55, 95% CI: 0.42-0.74, P = 6.86 × 10^-5 ). Both rs2071480 and rs1351383 significantly enhanced the transcriptional activity of PSMB9. Functional experiments revealed that silica exposure remarkably reduced the PSMB9 expression and caused cell apoptosis, while overexpression of PSMB9 markedly abolished silica-induced cell apoptosis. We here identified PSMB9 as a novel susceptibility gene for CWP and provided important insights into the further exploration of the CWP pathogenesis.

Nickel nanoparticles induce epithelial-mesenchymal transition in human bronchial epithelial cells via the HIF-1α/HDAC3 pathway

We and others have previously demonstrated that exposure to nickel nanoparticles (Nano-Ni) caused fibrogenic and carcinogenic effects; however, the underlying mechanisms are still not fully understood. This study aimed to investigate the effects of Nano-Ni on epithelial-mesenchymal transition (EMT) in human bronchial epithelial cells (BEAS-2B) and its underlying mechanisms since EMT is involved in both cancer pathogenesis and tissue fibrosis. Our results showed that exposure to Nano-Ni, compared to the control Nano-TiO2, caused a remarkable decrease in the expression of E-cadherin and an increase in the expression of vimentin and α-SMA, indicating an inducible role of Nano-Ni in EMT development in human bronchial epithelial cells. HIF-1α nuclear accumulation, HDAC3 upregulation, and decreased histone acetylation were also observed in the cells exposed to Nano-Ni, but not in those exposed to Nano-TiO2. Pretreatment of the cells with a specific HIF-1α inhibitor, CAY10585, or HIF-1α-specific siRNA transfection prior to Nano-Ni exposure resulted in the restoration of E-cadherin and abolished Nano-Ni-induced upregulation of vimentin and α-SMA, suggesting a crucial role of HIF-1α in Nano-Ni-induced EMT development. CAY10585 pretreatment also attenuated the HDAC3 upregulation and increased histone acetylation. Inhibition of HDAC3 with specific siRNA significantly restrained Nano-Ni-induced reduction in histone acetylation and restored EMT-related protein expression to near control levels. In summary, our findings suggest that exposure to Nano-Ni promotes the development of EMT in human bronchial epithelial cells by decreasing histone acetylation through HIF-1α-mediated HDAC3 upregulation. Our findings may provide information for further understanding of the molecular mechanisms of Nano-Ni-induced fibrosis and carcinogenesis.

[Two-dimensional equivalent mechanical modeling and finite element analysis of normal female pelvic floor system]

Objective: To construct the geometric model of the pelvic floor by a two-dimensional equivalent mechanics method, and to explore the effect of the shape and position of pelvic floor organs and tissues on the biomechanical properties of the pelvic floor under different abdominal pressure. Methods: A 28-year-old healthy and symmetrical married infertile female volunteer was included. The pelvic floor tissue was scanned in the supine position using a 3.0T magnetic resonance scanner (Philips Company, Holland). Based on the method of magnetic resonance imaging (MRI) two-dimensional parameter measurement and computer aided design, the geometric model and finite element model of the female pelvic floor were established, and the biomechanical characteristics of the pelvic floor support system under different abdominal pressure were analyzed. Results: In this study, four different working conditions of the pelvic floor force were simulated under 60, 99, 168, and 208 cmH₂O (1 cmH₂O=0.098 kPa) abdominal pressure loads. The trend was as follows: under the abdominal pressure load, the retrograde flexion of the uterus occurred, the cervical, the middle and upper vaginal segment and the levator anus muscle had the characteristic change of mechanical axial direction pointing to the sacrum and coccyx, and the deformation of the levator anus muscle in the horizontal direction was greater than that in the vertical direction. With the increase of the abdominal pressure, the maximum stress values of the pelvic floor whole system of healthy subjects under four different working conditions were 0.194 3, 0.389 6, 0.557 1, and 0.627 5 MPa, respectively, and the maximum displacement values were 10, 14, 21 and 25 mm, respectively. The maximum stress values of the cervical and vaginal middle and upper segment were 0.111 7, 0.161 8, 0.250 6, and 0.304 1 MPa, respectively, and the maximum displacement values were 3, 6, 9, and 11 mm, respectively. The maximum stress of the perineal body was 0.063 4, 0.119 6, 0.235 2, and 0.288 0 MPa, and the maximum displacement was 1, 2, 4, and 5 mm. The maximum stress values of the levator anus muscle were 0.194 3, 0.389 6, 0.557 1, and 0.627 5 MPa, and the maximum displacement values were 2, 4, 7, and 8 mm, respectively. The maximum stress and maximum displacement of pelvic organs increased with the increase of the abdominal pressure under different working conditions. The stress axial relationship of normal female pelvic floor was that the middle and upper segment of uterus and vagina mainly acted on the sacrococcyx and the levator anus muscle, and the lower vaginal segment acts on the perineal body. Conclusions: The two-dimensional equivalent mechanical modeling and finite element analysis of the female pelvic floor system can accurately reflect the biomechanical characteristics of the female pelvic floor, and the resultant stress direction of the pelvic organs points to the sacrum and coccyx. The sacrum and coccyx, levator anus and perineal body play important stress supporting roles in the pelvic floor system.

A protective role of autophagy in fine airborne particulate matter-induced apoptosis in LN-229 cells

Air pollution is a public health threat and global epidemiological studies have shown that ambient air pollutants are closely related to various poor health conditions, including neurodegenerative diseases. Here, we evaluated the toxic effects and the underlying mechanisms of fine airborne particulate matter (PM2.5) on human glioblastoma LN-229 cells. Our results showed that exposure of LN-229 cells to PM2.5 (≥ 200 μg/mL) significantly reduced cell viability. PM2.5 exposure increased autophagy, apoptosis, and ROS production in the cells. Pre-treatment with a ROS scavenger, catalase, or depletion of mtDNA (ρ0 cells) abolished PM2.5-induced autophagy and apoptosis. PM2.5 exposure also activated MAPK signals in cells, which were blocked by catalase pre-treatment or mtDNA depletion. Furthermore, inhibition of JNK, but not ERK1/2 or p38, attenuated PM2.5-induced autophagy and apoptosis in cells. Finally, suppression of autophagy with Bafilomycin A1 or Beclin 1 siRNA exacerbated PM2.5-induced apoptosis, indicating a protective role of autophagy against PM2.5-induced apoptosis. Our results demonstrated that exposure of LN-229 cells to PM2.5 caused autophagy and apoptosis through PM2.5-induced ROS generation, mainly by mitochondria, and JNK activation. Autophagy may have a transient protective response in PM2.5-induced apoptosis. These findings have important implications for understanding the potential neurotoxicity of PM2.5.

AB0276 COMPARISON OF METABOLIC DYSFUNCTION-ASSOCIATED FATTY LIVER DISEASE WITH NON-ALCOHOLIC FATTY LIVER DISEASE IN IDENTIFYING CARDIOVASCULAR RISK IN CHINESE INDIVIDUALS WITH RHEUMATOID ARTHRITIS

Background

The nomenclature from non-alcoholic fatty liver disease (NAFLD) to metabolic dysfunction-associated fatty liver disease (MAFLD) is considered to identify more cardiovascular disease (CVD) risk in general population, and patients with rheumatoid arthritis (RA) carry an excess risk for CVD.

Objectives

To compare MAFLD with NAFLD in identifying CVD risk in RA patients.

Methods

Clinical data from a Chinese RA cohort were retrospectively analyzed. Hepatic steatosis was defined by abdominal ultrasound examination. CVD risk in RA patients was estimated by the Prediction for Atherosclerotic Cardiovascular Disease Risk in China.

Results

Among 513 included RA patients, 78.4% were female and the mean ± SD age was 51.8 ± 12.6 years. The prevalence of MAFLD and NAFLD was 21.4% and 20.5%, respectively. 10.9% RA patients concomitated with CVD events and 32.4% had a high 10-year CVD risk. Multivariate logistic regression analysis showed that both MAFLD and NAFLD were associated with an increase in CVD events (MAFLD: AOR = 2.303 [95% CI 1.197, 4.429]; NAFLD: AOR = 2.478 [95% CI 1.185, 4.779] and high 10-year CVD risk (MAFLD: AOR = 3.184 [95% CI 1.777, 5.705]; NAFLD: AOR = 2.870 [95% CI 1.597, 5.156]; all p < 0.05). The NRI and IDI was -0.011 (95% CI -0.025, 0.003) and -0.002 (95% CI -0.007, 0.002) for CVD events, and 0.012 (95% CI -0.014, 0.038) and 0.005 (95% CI -0.003, 0.013; all p > 0.05) for high 10-year CVD risk, which indicated no additional CVD events and high 10-years CVD risk were identified when replacing NAFLD with MAFLD in RA patients.

Conclusion

Both MAFLD and NAFLD are associated with an increased CVD risk which implies the importance of early detection and management of MAFLD or NAFLD in RA patients. However, new nomenclature of MAFLD identify no additional CVD risk in RA patients.

Financial support:

National Natural Science Foundation of China (No. 81971527, 82171780 and 82101892), Science and Technology Program of Guangzhou (No. 202102010188 and 201904010088), and Guangdong Basic and Applied Basic Research Foundation (No. 2019A1515011928 and 2020A1515110061).

Figure 1.

The prevalence of MAFLD and NAFLD in RA patients with different stratification.

The prevalence in different genders (A) and ages groups (B); The prevalence in different disease activity groups (C) and disease duration (D); remission (CDAI ≤ 2.8); active (CDAI > 2.8).

Disclosure of Interests

None declared

Morphological classification and measurement of the glenoid cavity using three-dimensional reconstruction in a Chinese population

BACKGROUND

The purpose of this study was to examine the various shapes and record the morphometric data of the glenoid cavity in a Chinese population.

MATERIALS AND METHODS

A total of 501 scapulae, 247 left and 254 right, were analyzed. We classified the shape of the glenoid cavity as type Ⅰ (pear-shaped), type Ⅱ (oval-shaped), type Ⅲ (teardrop-shaped), type Ⅳ (calabash-shaped) or type Ⅴ (inverted comma-shaped). Four defined parameters, the superior-inferior glenoid diameter (AB), upper anterior-posterior glenoid diameter (CD), lower anterior-posterior glenoid diameter (EF) and glenoid index (GI), were measured, and five shapes were classified via three-dimensional reconstruction.

RESULTS

The mean AB, CD, EF and GI values of the glenoid were 3.51±0.41 cm, 1.95±0.28 cm, 2.60±0.34 cm, and 1.35±0.12 cm, respectively. The AB value of type Ⅱ glenoid cavities was significantly smaller than that of type Ⅰ and Ⅲ glenoid cavities (P<0.05), but the GI value of type Ⅱ glenoid cavities was larger than that of type Ⅲ cavities (P<0.05). The CD value showed a difference between type Ⅰ and type Ⅲ glenoid cavities (P<0.05). For the EF parameter, the values of type Ⅲ glenoid cavities were significantly larger than those of type Ⅰ and Ⅱ glenoid cavities (P<0.05).

CONCLUSIONS

Measuring and observing the variety of shapes and sizes of the glenoid cavity in Chinese people is conducive to for better understand its morphological features. This information can also guide surgeons in the design and selection of suitable prostheses for total shoulder arthroplasty in the Chinese population in order to reduce postoperative complications.

CT texture analysis-based nomogram for the preoperative prediction of visceral pleural invasion in cT1N0M0 lung adenocarcinoma: an external validation cohort study

AIM

To develop a nomogram based on computed tomography (CT) texture analysis for the preoperative prediction of visceral pleural invasion in patients with cT1N0M0 lung adenocarcinoma.

MATERIALS AND METHODS

A dataset of chest CT containing lung nodules was collected from two institutions, and all surgically resected nodules were classified pathologically based on the presence of visceral pleural invasion. Each nodule on the CT image was segmented automatically by artificial-intelligence software and its CT texture features were extracted. The dataset was divided into training and external validation cohorts according to the institution, and a nomogram for predicting visceral pleural invasion was developed and validated.

RESULTS

Of a total of 313 patients enrolled from two independent institutions, 63 were diagnosed with visceral pleural invasion. Three-dimensional (3D) CT long diameter, skewness, and sphericity, and chronic obstructive pulmonary disease were identified as independent predictors for visceral pleural invasion by multivariable logistic regression. The nomogram based on multivariable logistic regression showed great discriminative ability, as indicated by a C-index of 0.890 (95% confidence interval [CI]: 0.867-0.914) and 0.864 (95% CI: 0.817-0.911) for the training and external validation cohorts, respectively. Additionally, calibration of the nomogram revealed good predictive ability, as indicated by the Brier score (0.108 and 0.100 for the training and external validation cohorts, respectively).

CONCLUSIONS

A nomogram was developed that could compute the probability of visceral pleural invasion in patients with cT1N0M0 lung adenocarcinoma with good calibration and discrimination. The nomogram has potential as a reliable tool for clinical evaluation and decision-making.

MMP-3 activation is involved in copper oxide nanoparticle-induced epithelial-mesenchymal transition in human lung epithelial cells

Copper oxide nanoparticles (Nano-CuO) are widely used in medical and industrial fields and our daily necessities. However, the biosafety assessment of Nano-CuO is far behind their rapid development. Here, we investigated the adverse effects of Nano-CuO on normal human bronchial epithelial BEAS-2B cells, especially determined whether Nano-CuO exposure would cause dysregulation of MMP-3, an important mediator in pulmonary fibrosis, and its potential role in epithelial-mesenchymal transition (EMT). Our results showed that exposure to Nano-CuO, but not Nano-TiO₂, caused increased ROS generation, MAPKs activation, and MMP-3 upregulation. Nano-CuO-induced ROS generation was not observed in mitochondrial DNA-depleted BEAS-2B ρ⁰ cells, indicating that mitochondria may be the main source of Nano-CuO-induced ROS generation. Pretreatment of the cells with ROS scavengers or inhibitors or depleting mitochondrial DNA significantly attenuated Nano-CuO-induced MAPKs activation and MMP-3 upregulation, and pretreatment of cells with MAPKs inhibitors abolished Nano-CuO-induced MMP-3 upregulation, suggesting Nano-CuO-induced MMP-3 upregulation is through Nano-CuO-induced ROS generation and MAPKs activation. In addition, exposure of the cells to Nano-CuO for 48 h resulted in decreased E-cadherin expression and increased expression of vimentin, α-SMA, and fibronectin, which was ameliorated by MMP-3 siRNA transfection, suggesting an important role of MMP-3 in Nano-CuO-induced EMT. Taken together, our study demonstrated that Nano-CuO exposure caused mitochondrial ROS generation, MAPKs activation, and MMP-3 upregulation. Nano-CuO exposure also caused cells to undergo EMT, which was through Nano-CuO-induced dysregulation of ROS/MAPKs/MMP-3 pathway. Our findings will provide further understanding of the potential mechanisms involved in metal nanoparticle-induced various toxic effects including EMT and pulmonary fibrosis.

Nickel nanoparticle-induced cell transformation: involvement of DNA damage and DNA repair defect through HIF-1α/miR-210/Rad52 pathway

Background

Nickel nanoparticles (Nano-Ni) are increasingly used in industry and biomedicine with the development of nanotechnology. However, the genotoxic and carcinogenic effects of Nano-Ni and the underlying mechanisms are still unclear.

Methods

At first, dose–response (0, 10, 20, and 30 μg/mL) and time-response (0, 3, 6, 12, and 24 h) studies were performed in immortalized normal human bronchial epithelial cells BEAS-2B to observe the effects of Nano-Ni on DNA damage response (DDR)-associated proteins and the HIF-1α/miR-210/Rad52 pathway by real-time PCR or Western blot. Then, a Hsp90 inhibitor (1 µM of 17-AAG, an indirect HIF-1α inhibitor), HIF-1α knock-out (KO) cells, and a miR-210 inhibitor (20 nM) were used to determine whether Nano-Ni-induced Rad52 down-regulation was through HIF-1α nuclear accumulation and miR-210 up-regulation. In the long-term experiments, cells were treated with 0.25 and 0.5 µg/mL of Nano-Ni for 21 cycles (~ 150 days), and the level of anchorage-independent growth was determined by plating the cells in soft agar. Transduction of lentiviral particles containing human Rad52 ORF into BEAS-2B cells was used to observe the role of Rad52 in Nano-Ni-induced cell transformation. Nano-Ni-induced DNA damage and dysregulation of HIF-1α/miR-210/Rad52 pathway were also investigated in vivo by intratracheal instillation of 50 µg per mouse of Nano-Ni. gpt delta transgenic mice were used to analyze mutant frequency and mutation spectrum in mouse lungs after Nano-Ni exposure.

Results

Nano-Ni exposure caused DNA damage at both in vitro and in vivo settings, which was reflected by increased phosphorylation of DDR-associated proteins such as ATM at Ser1981, p53 at Ser15, and H2AX. Nano-Ni exposure also induced HIF-1α nuclear accumulation, miR-210 up-regulation, and down-regulation of homologous recombination repair (HRR) gene Rad52. Inhibition of or knocking-out HIF-1α or miR-210 ameliorated Nano-Ni-induced Rad52 down-regulation. Long-term low-dose Nano-Ni exposure led to cell malignant transformation, and augmentation of Rad52 expression significantly reduced Nano-Ni-induced cell transformation. In addition, increased immunostaining of cell proliferation markers, Ki-67 and PCNA, was observed in bronchiolar epithelial cells and hyperplastic pneumocytes in mouse lungs at day 7 and day 42 after Nano-Ni exposure. Finally, using gpt delta transgenic mice revealed that Nano-Ni exposure did not cause increased gpt mutant frequency and certain DNA mutations, such as base substitution and small base insertions/deletions, are not the main types of Nano-Ni-induced DNA damage.

Conclusions

This study unraveled the mechanisms underlying Nano-Ni-induced cell malignant transformation; the combined effects of Nano-Ni-induced DNA damage and DNA repair defects through HIF-1α/miR-210/Rad52 pathway likely contribute to Nano-Ni-induced genomic instability and ultimately cell transformation. Our findings will provide information to further elucidate the molecular mechanisms of Nano-Ni-induced genotoxicity and carcinogenicity.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-01117-7.

miR-770-5p inhibits the activation of pulmonary fibroblasts and silica-induced pulmonary fibrosis through targeting TGFBR1

Silicosis is a devastating interstitial lung disease arising from long-term exposure to inhalable silica. Regrettably, no therapy currently can effectively reverse the silica-induced fibrotic lesion. Emerging evidence has indicated that the dysregulation of microRNAs is involved in silica-induced pulmonary fibrosis. The aim of this study is to explore the expression pattern and underlying mechanisms of miR-770-5p in silica-induced pulmonary fibrosis. Consistent with our previous miRNA microarray analysis, the results of qRT-PCR showed that miR-770-5p expression was downregulated in silica-induced pulmonary fibrosis in humans and animal models. Administration of miR-770-5p agomir significantly reduced the fibrotic lesions in the lungs of mice exposed to silica dust. MiR-770-5p also exhibited a dramatic reduction in TGF-β1-activated human pulmonary fibroblasts (MRC-5). Transfection of miR-770-5p mimics significantly decreased the viability, migration ability, and S/G0 phase distribution, as well as the expression of fibronectin, collagen I, and α-SMA in TGF-β1-treated MRC-5 cells. Transforming growth factor-β receptor 1 (TGFBR1) was confirmed as a direct target of regulation by miR-770-5p. The expression of TGFBR1 was significantly increased in pulmonary fibrosis. Knockdown of TGFBR1 blocked the transduction of the TGF-β1 signaling pathway and attenuated the activation of MRC-5 cells, while overexpression of TGFBR1 effectively restored the activation of MRC-5 cells inhibited by miR-770-5p. Together, our results demonstrated that miR-770-5p exerted an anti-fibrotic effect in silica-induced pulmonary fibrosis by targeting TGFBR1. Targeting miR-770-5p might provide a new therapeutic strategy to prevent the abnormal activation of pulmonary fibroblasts in silicosis.

[Gene expression profiles of myopic mouse scleral fibroblasts: a bioinformatics analysis based on single-cell RNA sequencing]

OBJECTIVE

To investigate the changes in gene expression profiles of mouse scleral fibroblasts after myopia using single-cell RNA sequencing technology and explore the mechanism of dysfunction of the scleral fibroblasts in myopia.

METHODS

Normal healthy C57BL/6J mice were randomly divided into negative control group and myopia model group (n=6), and in the latter group, form deprivation myopia was induced in the right eye using translucent goggles. Single cell capture was performed in the right eye to obtain the scleral fibroblasts for RNA sequencing. The differentially expressed genes (DEGs) were screened and GO and KEGG analyses were carried out for functionally significant enrichment analysis.

RESULTS

Comparison of the gene expression profiles identified a total of 169 DEGs between the myopia model group and the negative control group (P>0.05), including 112 up-regulated and 57 down-regulated genes. GO function analysis showed that the DEGs were involved in leukocyte aggregation, differentiation and adhesion and other inflammation-related terms; ATP metabolism and binding, redox process, oxidative stress response, oxidative phosphorylation and other GO terms related to hypoxia; protein folding, protein transport, negative regulation of protein metabolism, endoplasmic reticulum (ER), ER cavity, ER stress and other biological processes related to protein and ER stress. KEGG analysis analysis showed that the significantly enriched pathways of the DEGs involved mainly the TCA cycle, oxidative phosphorylation, PPAR signaling, oxidative phosphorylation and other pathways related to hypoxia; MAPK signaling pathway related to inflammation; leukocyte transendothelial transport; and protein-related Parkinson's disease, Huntington's disease, protein digestion and absorption pathways.

CONCLUSION

The dysfunction of the scleral fibroblasts occurs in myopia through complex mechanisms involving inflammation, hypoxia, protein regulation, and ER stress-related gene expression and pathway regulation.

[Extraction of respiratory signals from chest tomosynthesis]

OBJECTIVE

To analyze the respiratory motion of the scanned object during acquisition of digital chest tomosynthesis (CTS) using a linear model.

OBJECTIVE

Respiratory signals were generated by extracting the motion of the diaphragm from the projection radiographs. The diaphragm trajectory obtained by dynamic programming (DP) was modeled and fitted, and according to the fitting of the data, the base motion curve and respiratory signal curve of the diaphragm were separated. Multipurpose chest phantom data, simulated digital Xcat phantom data and the datasets of 3 clinical patients were used to validate the performance of the proposed method.

OBJECTIVE

The motion trajectory of the diaphragm extracted from multipurpose chest phantom simulation data was linear. The respiratory signals could be effectively extracted from the 3 datasets of clinical patients in different respiratory states. The correlation coefficient between the respiratory signal extracted in Xcat simulation experiment and the original design was 0.9797.

OBJECTIVE

The linear model can effectively obtain the respiratory motion information of patients in real time, thus enabling the physicians to make clinical decisions on a rescan.

[Summary of the 16th Chinese Symposium on Burn Medicine and the 2021 Congress of Burn Medicine Branch of China International Exchange and Promotion Association for Medical and Healthcare and the 2021 International Summit Forum of Burns in Chongqing]

The 16th Chinese Symposium on Burn Medicine and the 2021 Congress of Burn Medicine Branch of China International Exchange and Promotion Association for Medical and Healthcare (CPAM) and the 2021 International Summit Forum of Burns in Chongqing was successfully held in Chongqing, from May 19th to 21st in 2021. A total of more than 500 specialists and scholars across the country attended the meeting. The theme of this congress was "Burn Medicine: standardization and internationalization" . With the meetings being held in the one main venue and three branch venues and elite forum, the related hot topics and difficult problems were discussed warmly in multiple dimensions. During the conference, Founding Congress of 6th Editorial Committee of Chinese Journal of Burns, the Standing Committee and whole Committee of Chinese Burn Association, and the Congress of Burn Medicine Branch of CPAM were held in pragmatic and efficient manners.

AB0125 CLINICAL CHARACTERISTICS OF RHEUMATOID ARTHRITIS PATIENTS WITH IGG4-RELATED SYNOVITIS

Background:

Elevated serum IgG4 (sIgG4) and IgG4+ plasma cell tissue infiltration are outstanding features of IgG4-related disease (IgG4-RD). However, elevated IgG4 is not specific for IgG4-RD. Our previous study reported elevated sIgG4 in 46% of rheumatoid arthritis (RA) patients (Mediators Inflamm 2014). Whether synovium from RA patients show similar characteristics of IgG4-RD and how about the clinical characteristics of RA patients with IgG4-related synovitis have not been reported yet.

Objectives:

To explore the serum and synovial IgG4 level and their correlation with disease indicators in RA.

Methods:

Active RA patients who underwent needle synovial biopsy with qualified synovium tissue were recruited. Demographic and clinical data were collected simultaneously. Synovium tissue were stained with H&E for Krenn synovitis score and immunohistochemistry for positive cell densities of CD20, CD38, IgG and IgG4. Serum IgG4 level was detected by immunonephelometry.

Results:

Among 96 RA patients recruited, 74 (77.1%) were female, the median age was 55.0 (46.0~61.0) years, disease duration was 42.0 (12.0~120.0) months and SDAI was 31.2 (22.1~42.8).

The median sIgG4 was 1.38 (0.86~2.42) g/L and 49(51.0%) patients had elevated sIgG4. Compared with those with normal sIgG4, RA patients with elevated sIgG4 had significantly higher levels of PrGA [7 (5~8) vs. 6 (4~7)], ESR [90 (64~116) mm/h vs. 61 (38~75) mm/h], CRP [46.20 (17.20~74.20) mg/L vs. 18.90 (9.46~49.20) mg/L], DAS28-ESR [6.3 (5.6~7.4) vs. 5.7 (4.7~6.4)], SDAI [34.2 (25.3~48.8) vs. 27.8 (18.9~35.9)] and HAQ-DI [1.70 (0.61~2.28) vs. 0.88 (0.40~1.75), all P<0.05]. Meanwhile, they also showed significantly higher synovial counts of CD38+ plasma cells [1240(559~2290) /mm2 vs. 1020(354~1777) /mm2], IgG4+ plasma cells [106 (39~249) /mm2 vs. 68 (3~123) /mm2], and higher ratio of IgG4+/IgG+ plasma cells [26.3 (15.5~38.0) % vs. 15.2 (0.9~24.7) %, all P<0.05].

The median IgG4+ plasma cells count was 83 (10~192) /mm2 and median ratio of IgG4+/IgG+ plasma cells was 19.1 (8.4~31.5)%. Both of them correlated positively with ESR, CRP and sIgG4 (r=0.216~0.394, all P<0.05). There were 46 (47.9%) patients with IgG4+ plasma cells >10/HPF, who had significant higher ESR [86 (50~109) mm/h vs. 65 (40~84) mm/h] and CRP [43.35 (16.93~77.85) mg/L vs. 26.15 (9.54~52.53) mg/L, both P<0.05] than those with IgG4+ plasma cells ≤10/HPF. There were 13 (13.5%) patients with the ratio of IgG4+/IgG+ plasma cells >40%, and 11 (11.5%) patients with both IgG4+ plasma cells >10/HPF and IgG4+/IgG+ plasma cells ratio >40% (IgG4-related synovitis). RA patients with IgG4-related synovitis had significant higher ESR than the others [106 (53~125) mm/h vs. 69 (41~91) mm/h, P<0.05].

There were 10 (10.4%) patients showing elevated sIgG4 and IgG4-related synovitis. Four patients completed 1-year follow-up and all of them achieved remission at 6th month (SDAI≤3.3, Figure 1). Only one patient had radiographic progression at 12th month.

Figure 1.

Dynamic disease activity of 4 RA patients with elevated sIgG4 and IgG4-related synovitis during 1-year follow-up.

Conclusion:

IgG4-related synovitis can be found in RA patients. Their clinical significance in disease characteristics and outcomes are worth further study.

Acknowledgements:

This work was supported by National Natural Science Foundation of China (no. 81971527, 81801606 and 81801605), Guangdong Natural Science Foundation (no. 2018A030313541 and 2018A030313690), Guangdong Medical Scientific Research Foundation (no. A2018062), Guangdong Basic and Applied Basic Research Foundation (no. 2019A1515011928 and 2020A1515110061), and Science and Technology Program of Guangzhou (no. 201904010088).

Disclosure of Interests:

None declared

AB0398 CASE SERIES OF PATIENTS WITH CHOLESTEROL CRYSTAL EMBOLISM SYNDROME THAT MIMICS SYSTEMIC VASCULITIS

Background:

Cholesterol crystal embolism (CCE) syndrome is a multisystemic disorder caused by small arteries cholesterol crystal emboli subsequent to small pieces of atheromatous plaques from the aorta or other major arteries break off. CCE is often overlooked because it mimics symptoms of systemic vasculitis due to its clinical characteristics such as ulceration and gangrene of toes, livedo reticularis, renal insufficiency. Acute inflammatory reactants such as ESR, CRP may elevate in CCE patients since the cholesterol crystals trigger a foreign-body inflammatory reaction around the arterioles.

Objectives:

This study aimed to explore the clinical characteristics of CCE patients, to make rheumatologists learn more about this disease.

Methods:

Peer-reviewed articles in the electronic databases Medline, PubMed, Science Citation Index, China Biomedical Literature Database (CBM), China Journal Full Text Database (CNKI), and WANFANG Data were searched using the terms “cholesterol crystal embolism syndrome”, “cholesterol embolism”, “atherosclerotic embolism”, “atherosclerotic nephropathy”, or “CCE”. Only articles or case reports containing detailed medical records of CCE patients were included. We also included CCE patients in our department.

Results:

A 66-year-old male CCE patient presented with multiple ulceration and gangrene of toes and heels (Figure 1), subacute renal insufficiency, and elevated CRP and ESR. This patient had been considered as “suspected systemic vasculitis” and was referred to our rheumatology department. Another 39 Chinese CCE patients from the above databases were qualified for analysis. Among these 40 patients, 87.5% (35/40) were male and the mean age was 68±6 years. The most common involved was kidney and 90% (36/40) of patients presenting with renal insufficiency including the progressive increase of serum creatinine, hematuria, proteinuria, or sudden (or sharp) aggravation of hypertension. Next common involved was skin that occurred in 87.5% (35/40) of patients, especially in the toes and heels. For skin manifestations, blue toe syndrome occurred in 82.5% (33/40) of patients, ulceration or gangrene in 25% (10/40), and livedo reticularis in 15% (6/40). Additionally, 12.5% (5/40) showed ocular involvement such as visual impairment and visual field defect. In 2 patients, embolized cholesterol crystal in retinal arteries that is called Hollenhorst plaques was detected by fundoscopy. There were 62.5% (25/40) of patients having elevated CRP or ESR. The positive rate for skin or subcutaneous biopsies was 58% (11/19) and for kidney biopsies was 100% (6/6). The precipitating factors preceding the occurrence of classical symptoms such as blue toe syndrome, livedo reticularis and/or subacute renal insufficiency is important for CCE diagnosis especially for patients who had contraindications or were intolerant to biopsy. The precipitating factors include endovascular intervention (80%), vascular surgery (5%), and anticoagulant or thrombolytic therapy (2.5%). Only 12.5% (5/40) of patients were spontaneous and didn’t have any predisposing factors. General interventions of CCE included statins (82.5%), antiplatelets (32.5%), and dialysis (32.5%). Twelve patients (30%) received glucocorticoids and 75% (9/12) of them renal function improved and ulceration healed (Figure 1). Among 36 patients who presented with renal insufficiency, the renal function returned to normal after treatment in 2 patients (5.6%), but 27 patients (75%) still showed abnormal renal function even though somewhat improved, and 7 patients (19.4%) needed renal replacement therapy or dialysis for maintenance.

Conclusion:

This study reported CCE patients had high prevalence of renal insufficiency, blue toe syndrome, and ulceration or gangrene of toes, as well as elevated CRP or ESR, thus rheumatologists should be alert to this disease as one of the differential diagnosis of systemic vasculitis, especially for elderly patients with evidence of atherosclerosis who undergo a recent cardiovascular procedure.

Disclosure of Interests:

None declared

AB0296 PASSIVE TRANSFER OF ANTI-SSA, ANTI-Ro52, AND ANTI-MITOCHONDRIAL M2 FROM INTRAVENOUS IMMUNOGLOBULIN PRODUCTS TO PATIENTS WITH RHEUMATIC DISEASES

Background:

Passive transfer of ANA and anti-SSA has been reported in patients with common variable immunodeficiency disorder who received intravenous immunoglobulin (IVIG). IVIG is also recommended to treat some special or life-threatening rheumatic diseases.

Objectives:

This study was aimed to explore whether any extractable nuclear antibodies (ENAs) were transferred to these rheumatic patients who received IVIG therapy.

Methods:

IVIG products of three batches were tested for ANA by using indirect immunofluorescent assay, and for ENAs by using line immunoassay (LIA) and chemiluminescence immunoassay (CLIA). These IVIG products were administrated to rheumatic patients at a dose of 20g/d×3 days (day1 to day3). Serum samples of these patients before IVIG (day0) and after IVIG (day4, day8, day10, day12, and more than one month) were tested by using LIA and CLIA. Anti-SSA was also detected using ELISA.

Results:

In these IVIG products, ANA was positive at a titer of 1:640 (cytoplasmic speckled) and 1:80 (speckled). Among 14 types of ENAs that could be tested using LIA, anti-SSA, anti-Ro52, anti-mitochondrial M2, and anti-centromere B antibodies were clearly detectable in IVIG products (Table 1). Likewise, another assay CLIA also detected the same positive autoantibodies in these products. LIA showed the highest concentration in anti-mitochondrial M2, while CLIA showed the highest concentration in anti-mitochondrial M2 and anti-Ro52. One 31-year-old male patient who was diagnosed as SLE (Figure 1) and one 72-year-old male patients who was diagnosed as necrotizing myositis received these IVIG products. Anti-SSA, anti-Ro52, anti-mitochondrial M2, but not anti-centromere B, were positive in the day4 serum samples, although all of these antibodies were negative at baseline (day0). The concentration of these antibodies decreased gradually as days passed and became undetectable around one month after IVIG.

Table 1.

The concentration of autoantibodies in intravenous immunoglobulin products

anti-SSAanti-Ro-52anti-mitochondrial M2anti-centromere BCut-offLIA(grey value)20±328±369±1019±4≥11CLIA (U/ml)333±107444±86434±66390±89>20ELISA (U/ml)90±13NANANA>20

LIA, line immunoassay; CLIA, chemiluminescence immunoassay; ELISA, enzyme linked immunosorbent assay

Conclusion:

This study preliminarily reported transient positivity of anti-SSA, anti-Ro52, and anti-mitochondrial M2 in rheumatic patients maybe because the passive transfer of these antibodies from IVIG products to the patients, although the potential influence of this transfer on the rheumatic diseases remained unknown.

Figure 1.

The concentration of autoantibodies in a 31-year-old male SLE patient receiving intravenous immunoglobulin at a dose of 20g/d×3 days (day1 to day3). Serum samples of these patients before IVIG (day0) and after IVIG (day4, day8, day10, day12, and day51) were tested by using line immunoassay (LIA) and chemiluminescence immunoassay (CLIA). Anti-SSA was also detected using ELISA. The horizontal red lines were the corresponding cut-off values of each assay.

Disclosure of Interests:

None declared

AB0394 CLINICAL CHARACTERISTICS OF EOSINOPHILIC GRANULOMATOSIS WITH POLYANGIITIS: A SINGLE-CENTER RETROSPECTIVE ANALYSIS ON 52 CASES OF CHINESE PATIENTS

Background:

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare and heterogeneous systemic vasculitis. Different patients or the same patient in different stages show different manifestations, which may lead to misdiagnosis and delay treatment.

Objectives:

To analyze the clinical characteristics in Chinese patients with EGPA.

Methods:

EGPA patients who fulfilled the 1990 ACR classification criteria were included between December 2003 and April 2020. The demographic and clinical characteristics were collected and analyzed retrospectively.

Results:

There were 52 EGPA patients recruited, 34 (65.4%) patients were males and the median age at onset was 47(38~55) years. The median duration from disease onset to diagnosis was 30(4~96) months. For initial symptoms, respiratory manifestations (61.5%) were the most common, including 42.3% patients beginning with asthma, followed by 21.2% with nose/paranasal sinuses manifestations. Respiratory medicine (53.8%) were the most common department at first visit, followed by rheumatology medicine (11.5%, Figure 1A). There were 44.2% EGPA patients definitely diagnosed at the department of rheumatology or after consultation by rheumatologists.

During the whole disease process, the most common clinical manifestations were asthma (88.5%), then nose/ paranasal sinuses (84.6%), pulmonary (76.9%) and nervous system (61.5%) manifestations, followed by constitutional symptom (44.2%), heart (36.5%) and skin (23.1%) involvement. Only 9.6% patients had gastrointestinal tract involvement and 3.8% had renal involvement (Figure 1B).

There were 46 (88.5%) patients showing the ratio of peripheral blood eosinophils >10% at diagnosis. Among the rest 6 patients, 3 had higher eosinophil ratio before diagnosis, while the other 3 patients had been treated with glucocorticoid before diagnosis, of whom 2 patients showed pathological eosinophil infiltration in lung or paranasal sinuses mucosa, respectively. There were 8(15.4%) patients with positive ANCA. Compared with EGPA patients with negative ANCA, they had lower incidence of asthma (62.5% vs. 93.2%), but higher incidence of constitutional symptoms (87.5% vs. 36.4%), arthralgia (50.0% vs. 6.8%) and renal involvement (25.0% vs. 0.0%), higher peripheral eosinophil count [2.06(0.80~4.51) ×109/L vs. 1.81(0.93~3.32) ×109/L], ESR [20(7~77) mm/h vs. 18(9~42) mm/h] and CRP [18.5(3.2~65.9) mg/L vs. 3.3(3.2~13.0) mg/L], higher Birmingham vasculitis activity score [17(10~22) vs. 13(9~15)] and vasculitis damage index [3(1~3) vs. 2(1~2), all P<0.05]. There were 21.2% EGPA patients showing poor prognostic factors according to five-factor score (FFS) and 34.6% patients according to the revised FFS.

Conclusion:

EGPA patients may have no asthma especially those with positive ANCA. Multi-disciplinary collaboration especially based on rheumatologists and pulmonologists should be emphasized for early identification and prompt treatment.

Figure 1.

Department at first visit (A) and clinical manifestations during the whole disease process of 52 Chinese EGPA patients(B).

Disclosure of Interests:

None declared

POS0452 SYNOVIAL MYELOID-STROMAL PATHOTYPE PREDICTS ONE-YEAR RADIOGRAPHIC PROGRESSION IN ACTIVE RHEUMATOID ARTHRITIS

Background:

Rheumatoid arthritis (RA) is a heterogeneous disease with variable prognosis. The cellular composition in synovium is the driving force of joint destruction in RA, and the predictive values of histopathological assessments on the clinical outcomes of RA have been identified. However, current synovial histopathological assessments mainly focus on the infiltrated immunocytes to distinguish RA synovium into different synovial pathotypes. Whether addition of stromal cells improve the accuracy of histopathological assessments remains unknow.

Objectives:

To distinguish synovial pathotypes of RA based on intercellular connection and explore their predictive value on one-year radiographic progression.

Methods:

Active RA patients who underwent needle synovial biopsy at baseline were recruited from a real-world prospective cohort. Clinical data were evaluated at baseline and 1, 3, 6, 12 months. Histopathologic assessments included Krenn synovitis score and semiquantitative score of immunohistochemical staining for CD20, CD38, CD4, CD8, CD68, CD31 and CD90. Cluster analysis was used to distinguish synovial pathotypes. The primary outcome was one-year radiographic progression defined as a change in total Sharp/van der Heijde modified score≥0.5 units.

Results:

1. Among 134 RA patients who received synovial biopsy at baseline and finished one-year follow-up, 105 had qualified synovial tissue. The mean age was 50.2±13.3 years with 77.1% female. The median disease duration was 24 (9-120) months. All patients were active RA, and 64.8%, 26.7% and 8.6% patients in high, moderate and low disease activity, respectively. There were 41 (39%) patients who have never been treated with corticosteroids or disease-modifying anti-rheumatic drugs.

2. During one-year follow-up, there were 48.6%, 63.8%, 71.4%, and 69.5% patients achieved CDAI LDA target, and 12.4%, 30.5%, 34.3%, and 32.4% patients achieved CDAI remission after 1, 3, 6, and 12 months, respectively. A total of 33 (31.4%) patients had radiographic progression.

3. All patients were divided into three clusters using cluster analysis based on the seven synovial cellular scores. Patients in cluster 1 (n=50, 47.6%) had higher scores of sublining CD68+ macrophages, CD31+ endothelial cells and CD90+ fibroblasts, thus named as myeloid-stromal pathotype. Patients in cluster 2 (n=26, 24.8%) had higher scores of CD20+ B cells, CD38+ plasma cells, CD4+ T cells and CD8+ T cells, thus named as lymphoid pathotype. Patients in cluster 3 (n=29, 27.6%) had lower scores of all seven cell types, thus named as pauci-cellular pathotype (Figure 1).

4. RA patients with baseline synovial myeloid-stromal pathotype showed higher rate of one-year radiographic progression versus lymphoid and pauci-cellular pathotypes (48% vs. 16.4%, P<0.001), whereas there was no difference between lymphoid and pauci-cellular pathotypes (11.5% vs. 20.7, P=0.475). Adjusted for confounding factors including age, sex, smoking, disease duration, RF status, ACPA status, CDAI, HAQ-DI and mTSS at baseline, multivariate logistic regression analysis showed that baseline synovial myeloid-stromal pathotype independently predicted one-year radiographic progression (AOR=3.602, 95%CI:1.257-10.324, P=0.017, Table 1).

Conclusion:

Baseline synovial myeloid-stromal pathotype in RA can predict one-year radiographic progression.

Funding:

This work was supported by National Natural Science Foundation of China (no. 81971527, 81801606 and 81801605), Guangdong Natural Science Foundation (no. 2018A030313541 and 2018A030313690), Guangdong Medical Scientific Research Foundation (no. A2018062), Guangdong Basic and Applied Basic Research Foundation (no. 2019A1515011928 and 2020A1515110061), and Science and Technology Program of Guangzhou (no. 201904010088).

Acknowledgements:

We thank all subjects and medical staff who generously contributed to this study.

Disclosure of Interests:

None declared

Effects of metal nanoparticles on tight junction-associated proteins via HIF-1α/miR-29b/MMPs pathway in human epidermal keratinocytes

Background

The increasing use of metal nanoparticles in industry and biomedicine raises the risk for unintentional exposure. The ability of metal nanoparticles to penetrate the skin ranges from stopping at the stratum corneum to passing below the dermis and entering the systemic circulation. Despite the potential health risks associated with skin exposure to metal nanoparticles, the mechanisms underlying the toxicity of metal nanoparticles on skin keratinocytes remain unclear. In this study, we proposed that exposure of human epidermal keratinocytes (HaCaT) to metal nanoparticles, such as nickel nanoparticles, dysregulates tight-junction associated proteins by interacting with the HIF-1α/miR-29b/MMPs axis.

Methods

We performed dose-response and time-response studies in HaCaT cells to observe the effects of Nano-Ni or Nano-TiO₂ on the expression and activity of MMP-2 and MMP-9, and on the expression of tight junction-associated proteins, TIMP-1, TIMP-2, miR-29b, and HIF-1α. In the dose-response studies, cells were exposed to 0, 10, or 20 μg/mL of Nano-Ni or Nano-TiO₂ for 24 h. In the time-response studies, cells were exposed to 20 μg/mL of Nano-Ni for 12, 24, 48, or 72 h. After treatment, cells were collected to either assess the expression of mRNAs and miR-29b by real-time PCR or to determine the expression of tight junction-associated proteins and HIF-1α nuclear accumulation by Western blot and/or immunofluorescent staining; the conditioned media were collected to evaluate the MMP-2 and MMP-9 activities by gelatin zymography assay. To further investigate the mechanisms underlying Nano-Ni-induced dysregulation of tight junction-associated proteins, we employed a HIF-1α inhibitor, CAY10585, to perturb HIF-1α accumulation in one experiment, and transfected a miR-29b-3p mimic into the HaCaT cells before Nano-Ni exposure in another experiment. Cells and conditioned media were collected, and the expression and activities of MMPs and the expression of tight junction-associated proteins were determined as described above.

Results

Exposure of HaCaT cells to Nano-Ni resulted in a dose-dependent increase in the expression of MMP-2, MMP-9, TIMP-1, and TIMP-2 and the activities of MMP-2 and MMP-9. However, exposure of cells to Nano-TiO₂ did not cause these effects. Nano-Ni caused a dose-dependent decrease in the expression of miR-29b and tight junction-associated proteins, such as ZO-1, occludin, and claudin-1, while Nano-TiO₂ did not. Nano-Ni also caused a dose-dependent increase in HIF-1α nuclear accumulation. The time-response studies showed that Nano-Ni caused significantly increased expressions of MMP-2 at 24 h, MMP-9 at 12, 24, and 48 h, TIMP-1 from 24 to 72 h, and TIMP-2 from 12 to 72 h post-exposure. The expression of miR-29b and tight junction-associated proteins such as ZO-1, occludin, and claudin-1 decreased as early as 12 h post-exposure, and their levels declined gradually over time. Pretreatment of cells with a HIF-1α inhibitor, CAY10585, abolished Nano-Ni-induced miR-29b down-regulation and MMP-2/9 up-regulation. Introduction of a miR-29b-3p mimic into HaCaT cells by transfection before Nano-Ni exposure ameliorated Nano-Ni-induced increased expression and activity of MMP-2 and MMP-9 and restored Nano-Ni-induced down-regulation of tight junction-associated proteins.

Conclusion

Our study herein demonstrated that exposure of human epidermal keratinocytes to Nano-Ni caused increased HIF-1α nuclear accumulation and increased transcription and activity of MMP-2 and MMP-9 and down-regulation of miR-29b and tight junction-associated proteins. Nano-Ni-induced miR-29b down-regulation was through Nano-Ni-induced HIF-1α nuclear accumulation. Restoration of miR-29b level by miR-29b-3p mimic transfection abolished Nano-Ni-induced MMP-2 and MMP-9 activation and down-regulation of tight junction-associated proteins. In summary, our results demonstrated that Nano-Ni-induced dysregulation of tight junction-associated proteins in skin keratinocytes was via HIF-1α/miR-29b/MMPs pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-021-00405-2.

[Four-dimensional cone-beam CT reconstruction based on motion-compensated robust principal component analysis]

OBJECTIVE

To propose a motion compensation reconstruction method based on robust principal component analysis (RPCA) to reduce the influence of streak artifacts on accurate estimation of interphase motion deformation fields.

OBJECTIVE

We propose a RPCA motion compensation reconstruction algorithm to improve the estimation of motion deformation fields based on the traditional MC-FDK algorithm. RPCA was used to decompose the cone-beam computed tomography (CBCT) images into low-rank and sparse components, and the motion deformation fields between different phase images were then estimated using Horn and Schunck optical flow method from the low-rank images to reduce the influence of striping artifacts on the accuracy of estimation of interphase motion deformation fields. The performance of the algorithm was evaluated using simulation data and real data. The simulation phantom data was obtained by back-projection of 4D-CT images acquired from Philips 16-slice spiral CT using MATLAB software programming according to the scanning geometry of Varian Edge accelerator. The real patient data were obtained using the Elekta Synergy system of CBCT scanning system with half-fan mode CB projection data from lung cancer patients.

OBJECTIVE

Compared with images reconstructed using the traditional MC-FDK algorithm, the reconstructed image using the proposed method had clearer tissue boundaries with reduced motion artifact was reduced. The results of phantom data reconstruction showed that compared with the MC- FDK algorithm, the proposed algorithms resulted in improvements of PSNR by 25.4% and SSIM by 7.6%; compared with the FDK algorithm, PSNR was improved by 37.9% and SSIM by 17.6%.

OBJECTIVE

The proposed algorithm can achieve accurate estimation of inter-phase motion deformation fields and improve the quality of the reconstructed CBCT images.

MiR-181a-5p inhibits goose granulosa cell viability by targeting SIRT1

1. Granulosa cells (GCs) are involved in folliculogenesis, follicular development, and atresia. Previous studies have shown that microRNA-181a-5p (miR-181a-5p) and sirtuin 1 (SIRT1) are involved in GC proliferation and apoptosis, and SIRT1 has been predicted as one target of miR-181a-5p. However, there are few studies with poultry.2. Quantitative real-time PCR (qRT-PCR) was used to detect the expression level of miR-181a-5p in granulosa layers during geese ovarian follicular development. A methyl thiazolyl tetrazolium (MTT) assay was performed to assess the viability of geese granulosa cells treated with miR-181a-5p mimic or inhibitor. The binding sites between the SIRT1 3'-UTR region and miR-181a-5p were evaluated using a luciferase reporter assay system. SIRT1 mRNA levels were detected using qRT-PCR after transfection with miR-181a-5p mimic and inhibitor.3. The miR-181a-5p suppressed geese GC viability and regulated the mRNA expression of viability-related genes in geese GCs. SIRT1 was a target gene of miR-181a-5p and miR-181a-5p suppressed its mRNA expression.4. The miR-181a-5p may target and inhibit SIRT1 expression, thus suppressing GC viability by regulating viability-related key genes.

The role of miR-21 in nickel nanoparticle-induced MMP-2 and MMP-9 production in mouse primary monocytes: In vitro and in vivo studies

Exposure to metal nanoparticles causes both pulmonary and systemic effects. Nanoparticles can enter the circulation and act directly or indirectly on blood cells, such as monocytes. Monocytes/macrophages are among the first cells to home to inflammatory sites and play a key role in the immune response. Here we investigated the effects of nickel nanoparticles (Nano-Ni), partially [O]-passivated Nano-Ni (Nano-Ni-P), and carbon-coated Nano-Ni (Nano-Ni-C) on MMP-2 and MMP-9 production in mouse primary monocytes both in vitro and in vivo and explored the potential mechanisms involved. The dose- and time-response studies showed that exposure of primary monocytes from wild-type (WT) mice to 30 μg/mL of Nano-Ni for 24 h caused significant MMP-2 and MMP-9 production; therefore, these dose and time point were chosen for the following in vitro studies. Nano-Ni and Nano-Ni-P caused miR-21 upregulation, as well as MMP-2, MMP-9, TIMP-1 and TIMP-2 upregulation in monocytes from WT, but not miR-21 knock-out (KO), mice, indicating the important role of miR-21 in Nano-Ni-induced MMPs and TIMPs upregulation. However, Nano-Ni-C did not cause these effects, suggesting surface modification of Nano-Ni, such as carbon coating, alleviates Nano-Ni-induced miR-21 and MMPs upregulation. These results were further confirmed by in vivo studies by intratracheal instillation of nickel nanoparticles into WT and miR-21 KO mice. Finally, our results demonstrated that exposure of primary monocytes from WT mice to Nano-Ni and Nano-Ni-P caused downregulation of RECK, a direct miR-21 target, suggesting the involvement of miR-21/RECK pathway in Nano-Ni-induced MMP-2 and MMP-9 production.

miR-21 mediates nickel nanoparticle-induced pulmonary injury and fibrosis

We and other groups have demonstrated that exposure to nickel nanoparticles (Nano-Ni) results in severe and persistent lung inflammation and fibrosis, but the underlying mechanisms remain unclear. Here, we propose that miR-21 may play an important role in Nano-Ni-induced lung inflammation, injury, and fibrosis. Our dose- and time-response studies demonstrated that exposure of C57BL/6J (WT) mice to Nano-Ni resulted in upregulation of miR-21, proinflammatory cytokines, and profibrotic mediators. Histologically, exposure to Nano-Ni caused severe pulmonary inflammation and fibrosis. Based on the dose- and time-response studies, we chose a dose of 50 µg of Nano-Ni per mouse to compare the effects of Nano-Ni on WT with those on miR-21 KO mouse lungs. At day 3 post-exposure, Nano-Ni caused severe acute lung inflammation and injury that were reflected by increased neutrophil count, CXCL1/KC level, LDH activity, total protein concentration, MMP-2/9 protein levels and activities, and proinflammatory cytokines in the BALF or lung tissues from WT mice, which were confirmed histologically. Although Nano-Ni had similar effects on miR-21 KO mice, the above-mentioned levels were significantly lower than those in WT mice. Histologically, lungs from WT mice exposed to Nano-Ni had infiltration of a large number of polymorphonuclear (PMN) cells and macrophages in the alveolar space and interstitial tissues. However, exposure of miR-21 KO mice to Nano-Ni only caused mild acute lung inflammation and injury. At day 42 post-exposure, Nano-Ni caused extensive pulmonary fibrosis and chronic inflammation in the WT mouse lungs. However, exposure of miR-21 KO mice to Nano-Ni only caused mild lung fibrosis and chronic lung inflammation. Our results also showed that exposure to Nano-Ni caused upregulation of TGF-β1, phospho-Smad2, COL1A1, and COL3A1 in both WT and miR-21 KO mouse lungs. However, levels were significantly lower in miR-21 KO mice than in WT mice, except TGF-β1, which was similar in both kinds of mice. Decreased expression of Smad7 was observed in WT mouse lungs, but not in miR-21 KO mice. Our results demonstrated that knocking out miR-21 ameliorated Nano-Ni-induced pulmonary inflammation, injury, and fibrosis, suggesting the important role of miR-21 in Nano-Ni-induced pulmonary toxicity.

Activation of NLRP3 inflammasome in hepatocytes after exposure to cobalt nanoparticles: The role of oxidative stress

With the increased use of nanomaterials and increased exposure of humans to various nanomaterials, the potential health effects of nanomaterials cannot be ignored. The hepatotoxicity of cobalt nanoparticles (Nano-Co) is largely unknown and the underlying mechanisms remain obscure. The purpose of this study was to exam the hepatotoxicity induced by Nano-Co and its potential mechanisms. Our results showed that exposure of human fetal hepatocytes L02 to Nano-Co caused a dose- and a time-dependent cytotoxicity. Besides the generation of reactive oxygen species (ROS) and mitochondrial reactive oxygen species (mtROS), exposure to Nano-Co also caused activation of NOD-like receptor protein 3 (NLRP3) inflammasome in hepatocytes. After silencing NLRP3, one component of NLRP3 inflammasome, expression by siRNA strategy, we found that upregulation of NLRP3-related proteins was abolished in hepatocytes exposed to Nano-Co. Using antioxidants to scavenge ROS and mtROS, we demonstrated that Nano-Co-induced mtROS generation was related to Nano-Co-induced NLRP3 inflammasome activation. Our findings demonstrated that Nano-Co exposure may promote intracellular oxidative stress damage, and mtROS may mediate the activation of NLRP3 inflammasome in hepatocytes exposed to Nano-Co, suggesting an important role of ROS/NLRP3 pathway in Nano-Co-induced hepatotoxicity. These results provide scientific insights into the hepatotoxicity of Nano-Co and a basis for the prevention and treatment of Nano-Co-induced cytotoxicity.

AB0405 ABNORMAL BLOOD LIPID METABOLISM IN PREMENOPAUSAL FEMALE SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS IS RELATED TO HYPERURICEMIA AND PROTEINURIA

Background:

1. Hyperuricemia is often associated with abnormal lipid metabolism. We reported premenopausal female systemic lupus erythematosus (SLE) patients had elevated blood UA levels[1]. Do these patients also have hyperlipidemia?

2. Estrogen has certain effect on blood lipid metabolism, whether the blood lipid levels of premenopausal female SLE patients who have the background of hyperestrogen function are affected by estrogen and its receptors?

Objectives:

To investigate the relationships between blood lipids and serum UA level, estrogen receptors (ERs) as well as ER antibodies in premenopausal female SLE patients.

Methods:

123 premenopausal female SLE patients (SLE group) were divided into normal CH group (n=93) and high CH group (n=30, CH>5.17mmol /l), and 40 healthy premenopausal females served as the control group. The blood lipid levels of the SLE group and the control group were compared, and the blood levels of lipid, UA, estrogen, ERs and ER antibodies were compared between the two SLE subgroups. Linear regression was used to analyze the influencing factors of blood CH.

Results:

1. In SLE group, the blood level of TG was significantly higher than that of the control group (1.67±1.10 vs. 0.87±0.47, P<0.001), while the levels of blood CH, LDL, HDL were comparable to the control group (all with P> 0.05).

2. The mean blood CH level of the SLE patients with hyperuricemia was 5.57 ± 2.44mmol/l, which was significantly higher than that of patients with normal UA level (3.98 ± 1.30mmol / l, P <0.001).

3. The serum UA, CRE, CH, TG, LDL, and 24-hour urinary protein quantification (24h UPRO) in the high CH SLE subgroup were significantly higher than those in the normal CH SLE subgroup (all with P <0.05). There were no significant differences in serum estrogen, ERs and ER antibodies between the two subgroups, Table 1.

4. Linear regression showed that serum UA level and 24h UPRO were the dangerous effects of elevated blood CH in the premenopausal female SLE patients, Table 2.

Conclusion:

Compared with healthy female of the same age range, the premenopausal female SLE patients are more likely to have abnormal lipid metabolism, which is related to kidney damage and abnormal UA metabolism.

References:

[1]Haijun Liu, Xiaoyan Cai, Lie Dai, et al. Elevated uric acid levels in premenopausal female systemic lupus erythematosus patients: association with potential or existing renal damage. Eur J Inflamm,2018,16:1-6.

Table 1.

Some clinical indicators, estrogen, ERs and ER antibodies in the premenopausal female SLE patients

High CH group (n=30)Normal CH group(n=93)PAge(years)31.40±7.4028.12±7.230.039UA(μmol/l)433.40±192.90310.10±129.570.002CRE(μmol/l)112.07±87.0972.81±91.960.039CH(mmol/l)7.07±2.053.72±0.93<0.001TG(mmol/l)2.27±1.571.48±0.840.013LDL(mmol/l)4.48±1.462.29±0.67<0.001HDL(mmol/l)1.02±0.721.97±0.430.721Estrogen(pg/ml)73.53±47.7469.42±55.480.717ERα(pg/ml)45.94±31.0643.34±31.050.684ERβ(pg/ml)16.65±28.6713.70±25.090.589Anti-ERα(ng/ml)59.75±33.8755.16±31.340.496Anti-ERβ(ng/ml)89.73±49.0371.73±41.740.05224h UPRO(g/24h)2.82±3.820.39±0.560.002Positive UBLD(%)20(66.67)31(33.33)0.01SLEDAI13.18±4.237.39±6.180.025

ER, estrogen receptor; 24h UPRO, 24-hour urinary protein quantification; UBLD, urinary blood.

Table 2.

Relationships between blood CH level and clinical indicators in in the premenopausal female SLE patients

VariableUnstandardized CoefficientsStandardized CoefficientstP95%CIBSEM24h UPRO0.3530.0720.4004.932<0.0010.211~0.495UA0.0030.0010.2493.0580.0030.001~0.005Constant3.1460.3598.754<0.0012.434~3.857

UA, uric acid; 24h UPRO, 24-hour urinary protein quantification.

Disclosure of Interests: :

None declared

OP0095 A DECISION MODEL OF LABIAL GLAND BIOPSY BASED ON B-MODE ULTRASONOGRAPHY WITH SHEAR-WAVE ELASTOGRAPHY IN PATIENTS WITH SUSPECTED SJÖGREN’S SYNDROME

Background:

Focal lymphocytic sialadenitis defined as focus score (FS) ≥1 on labial gland (LG) biopsy plays an integral role in various classification criteria of Sjögren’s syndrome (SS). However, suspected patients often hesitate to receive a biopsy; and rheumatologists hope a decision for biopsy based on a high predicted incidence of FS≥1, or against biopsy based on an absolutely low predicted incidence.

Objectives:

To build a decision model of LG biopsy based on B-mode ultrasonography (US) with shear-wave elastography (SWE) in patients with suspected SS.

Methods:

Patients who had at least one symptom of oral dryness (based on AECG questions) or had anti-SSA positive were recruited and signed a written informed consent. Bilateral parotid (PG) and submandibular glands (SMG) were examined with B-mode US which graded the echostructure of each gland on a scoring system scaled 0 to 4 (US score), and SWE which described the elasticity of glands. Then LG biopsy was performed.

Results:

(1)Ninety-one patients whose mean age was 43±15 years were enrolled and 93% of them were female. Anti-SSA was detected in 77 patients (85%) and 28 patients (31%) showed unstimulated whole saliva flow rate (USFR)≤0.1mL/mim. There were 57 patients (63%) showing FS≥1 on LG biopsy. Sixty-three patients (69%) were classified as primary SS, 10 patients (10%) were secondary SS, 18 patients (20%) were uCTD and one patient was RA without SS.

(2)US scores were equal between PG and SMG in 59 patients (65%), while the rest patients showed different US scores between two glands: 7 patients (8%) showed higher US scores in PG and 25 patients (27%) showed higher scores in SMG. In each pair of glands US scores were equal. SWE values in PG or SMG of US score 1, 2 or 3 were significantly higher than those of US score 0, while SWE values in glands of US score 4 became declined and showed no significant difference from those with US score 0 (Figure 1A).

(3)Heatmap showed US scores in either major salivary gland of patients with FS≥1 on LG biopsy were significantly higher than those with FS<1 (all p<0.001, Figure 1B). ROC curve showed a total US score (including bilateral PG and SMG) ≥9 and a total SWE value (including bilateral PG and SMG)≥30 could significantly recognize patients with FS≥1, respectively with specificity of 100% and 93% (Figure 1C). In this cohort, among 51 patients with a total US score ≥9 and/or a total SWE value≥30, 49 patients (96%) showed FS≥1 on LG biopsy; while two outliers showed total US scores were both 8 although combined SWE values≥30. Other 29 patients showed total US scores≤6 with total SWE values <30 and only one patient (3%) showed FS≥1 on LG biopsy. The remaining 11 patients showed total US scores were 8 with total SWE values <30 and 64% of them (n=7) showed FS≥1.

Conclusion:

A preliminary decision model of LG biopsy based on B-mode US with SWE in patients with suspected SS were built in Table 1. For example, rheumatologists should reassess the need for biopsy if the incidence of FS≥1 would be <5%. Another cohort of patients with suspected SS is needed for further validation.

Table 1.

A preliminary decision model of LG biopsy based on B-mode US with SWE in patients with suspected SS

Algorithm*Comments on the decision of LG biopsyA total US score≥9 and/or a total SWE≥30The specificity of FS≥1 on biopsy is >93%. Biopsy is recommended. In some special cases (e.g. contraindicated to biopsy), this item is a potential alternative to LG biopsy.A total US score 7~8 with a total SWE <30It is hard to predict the result of FS, so biopsy is strongly recommended.A total US score≤6 with a total SWE <30The incidence of FS≥1 would be <5%. Rheumatologists should reassess the need for biopsy.

References:

None

Disclosure of Interests:

None declared

Intracellular ATP Delivery Causes Rapid Tissue Regeneration via Upregulation of Cytokines, Chemokines, and Stem Cells

We have reported accelerated wound healing induced by intracellular ATP delivery in rabbits, through early massive accumulation, in situ proliferation, and M2 polarization of macrophages. Granulation tissue started to grow within first 24 h of treatment and continued the growth till the wound cavity is completely covered. However, the mechanisms underlying this macrophage response are totally unclear because no one has ever reported this before. In this study, we performed a preliminary exploration of the possible mechanisms by focusing on the roles of cytokines, growth factors, and stem cells in this process. Among the 33 adult rabbits, 18 were used for cytokine measurements and the remaining were used for histological and immunohistochemical studies. Four wounds were created on the ventral side of each ear. Two wounds on one side were treated with ATP-vesicles (10 mM ATP), and the other two were treated with controls (normal saline or Regranex). Dressing changes were made daily and the rabbits were sacrificed at 5 h, 12 h, and 1, 2, 3, 4, 6, 9, 15, and 26 days after wounding. Tissue samples were analyzed for cytokines and growth factors using real-time PCR and immunohistochemical staining. The control wounds showed an immediate increase in proinflammatory cytokines after wound creation but no further increase after this initial spike. The growth factor levels in the control wounds remained unchanged throughout the study. Conversely, the wounds treated with ATP-vesicles showed significantly higher expression of MCP-1 and stem cell markers (CD44, CD106, CD146, and CD34) at day 1, significantly higher IL-1β and TNF-α expression from day 1–4, and significantly higher VEGF-A, VEGF-D, and VEGFR-2 expression from day 4–6 when compared to the controls. The significant upregulation of these factors corresponded to the very early and rapid macrophage accumulation, in situ proliferation, and M2 polarization, resulting in unprecedented rapid granulation tissue generation due to direct macrophage collagen production and neovascularization.

[Interpretation of clinical practice guideline for anorectal day surgery 2019 edition]

As the rapid development of minimally invasive techniques, anesthesia, and enhanced recovery after surgery (ERAS), anorectal day surgery receiving more and more attention by improving efficiency of medical care while reducing cost and hospitalized infection. However, day surgery also faces the challenge of completing the whole process from patient admission to discharge within 24 hours. Therefore, establishing a reasonable and detailed day surgery process is the cornerstone to guarantee safe medical practice and patients satisfaction. National Clinical Research Center for Geriatric Disorders (Xiangya), together with China Ambulatory Surgery Alliance formulates the clinical practice guideline for anorectal day surgery 2019 edition. Here we make some interpretations of the guidelines on the detailed process of anorectal day surgery, including indication, preoperative examination, preoperative risk evaluation, health education, assessment of day surgery anesthesia and before leaving postanesthesia care unit (PACU), postoperative management, assessment of discharge and follow-up, for the convenience of various medical centers.

[Prenatal and postnatal ultrasound assessment and clinical prognostic analysis for Ebstein anomaly]

Objective: To investigate the echocardiographic features of fetal Ebstein's anomaly (EA) and to analyze its clinical outcome and prognosis. Methods: A retrospective case-control study was conducted to analyze the echocardiographic features in fetus with EA. Thirty-five EA fetuses (EA group) and 35 normal fetuses matched for gestational age (control group) were enrolled. The main echocardiographic parameters of the two groups were collected and compared. According to the direction of blood flow in the ductus arteriosus (DA),fetuses in EA group were divided into DA reverse perfusion subgroup (n=11) and normal DA blood flow subgroup (n=24). The echocardiographic parameters and GOSE scores were compared between the two subgroups. The echocardiographic features of EA and the difference of fetal hemodynamics were summarized,and the clinical outcome of EA fetus was evaluated by GOSE score. Chi-square test Rank sum test or t test were used for comparison between groups. Results: Nineteen (54%) of the 35 patients terminated the pregnancy and 16 (46%) continued pregnancy until delivery during follow-up. Compared with the normal fetus group,the cardiothoracic ratio was significantly higher (0.47±0.11 vs. 0.34±0.01, t=6.640, P<0.01) and the transverse diameter ratio of right atrium to left atrium was significantly greater (1.42±0.38 vs. 1.08±0.11, t=5.030, P<0.01) in the EA group, and the ratio of pulmonary artery diameter to aortic diameter was significantly lower in the EA group (1.04±0.21 vs. 1.20±0.15, t=-3.770, P<0.01). Compared with the normal DA blood flow subgroup,the GOSE scores ≥ 1.5 was more frequently seen (7/11 vs. 3/24, P=0.004) and the ratio of pulmonary artery diameter to aortic diameter was significantly lower (0.91±0.18 vs. 1.24±0.20, t=-4.696, P=0.002) in the DA reverse perfusion subgroup. Six of the 16 delivery cases underwent EA corrective surgery after birth with 100% successful rate of operation. Among the 6 cases,two had preoperative GOSE score of ≥1.5 who were considered as severe cases,and four had low GOSE score of<1.5. The remaining ten cases who had not undergone the corrective surgery were followed up routinely. Conclusion: Prenatal hemodynamics of EA combined with GOSE score can more accurately evaluate the severity and prognosis of fetal EA, reduce unnecessary labor induction, and improve postpartum cure rate and clinical outcomes.

[Summary of the 15th Syposium on Chinese Burn Medicine and the 2nd Congress of Burn Medicine Branch of China International Exchange and Promotion Association for Medical and Healthcare]

The 15th Syposium on Chinese Burn Medicine and the 2nd Congress of Burn Medicine Branch of China International Exchange and Promotion Association for Medical and Healthcare (CPAM) was successfully held in Suzhou, from June 20th to 22th in 2019. A total of 400 specialists and scholars across the country attended the meeting. Focusing on the theme of " Guide and consensus: exploration and consideration " , with form of one main meeting place and two branch meeting places, the related hot and difficult problems were discussed warmly. During the conference, Working Conference of Editorial Committee of Chinese Journal of Burns, Standing Committee of the Chinese Burn Association, and the Congress of Burn Medicine Branch of CPAM were held.

Application of Gelatin Zymography in Nanotoxicity Research

Gelatin zymography is a relatively simple, inexpensive, and powerful technique to detect proteolytic enzymes capable of degrading gelatin from various biological sources. It has been used particularly to detect the two members of the matrix metalloproteinase family, MMP-2 (gelatinase A) and MMP-9 (gelatinase B), due to their potent gelatin-degrading activity. MMP-2 and MMP-9 are also able to degrade a number of extracellular matrix molecules including type IV, V, and XI collagens, laminin, and aggrecan core protein, thus making them important in the nanotoxicity research. In this technique, proteins are separated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE), and gelatinases, activated by SDS, digest gelatin embedded in the gel. After staining with Coomassie Brilliant Blue R-250, areas of degradation are visible as clear bands against a blue-stained background. Here, we describe the detailed procedure for gelatin zymography.

[Review of survey method for human time-activity pattern and its application in the exposure assessment of air pollutants]

Time activity pattern refers to the time and behavior of people at different locations. The knowledge of time-activity pattern is essential for air pollution exposure assessment when direct personal exposure monitoring can't not be conducted, because air pollutant concentrations may vary significantly by location and activity. This review is focused on the survey method for human time-activity pattern and its application in the exposure assessment of air pollutants. After comparing the diary-reported trips and Global Positioning System (GPS) recording method, we believed that diary-reported trips were more reliable in describing comprehensive and detail records of the behavior and environmental circumstances while GPS-recorded trend to maintain sound information of time, location and transportations. Meanwhile, according to different subjects, the air pollution exposure model could be divided for population and individuals. There were great difference between two types of model in many areas, including the required information about time, activity and microenvironment.

Comparative mouse lung injury by nickel nanoparticles with differential surface modification

BACKGROUND

Previous studies have demonstrated that exposure to nickel nanoparticles (Nano-Ni) causes oxidative stress and severe, persistent lung inflammation, which are strongly associated with pulmonary toxicity. However, few studies have investigated whether surface modification of Nano-Ni could alter Nano-Ni-induced lung injury, inflammation, and fibrosis in vivo. Here, we propose that alteration of physicochemical properties of Nano-Ni through modification of Nano-Ni surface may change Nano-Ni-induced lung injury, inflammation, and fibrosis.

METHODS

At first, dose-response and time-response studies were performed to observe lung inflammation and injury caused by Nano-Ni. In the dose-response studies, mice were intratracheally instilled with 0, 10, 20, 50, and 100 μg per mouse of Nano-Ni and sacrificed at day 3 post-exposure. In the time-response studies, mice were intratracheally instilled with 50 µg per mouse of Nano-Ni and sacrificed at days 1, 3, 7, 14, 28, and 42 post-instillation. At the end of the experiment, mice were bronchoalveolar lavaged (BAL) and the neutrophil count, CXCL1/KC level, LDH activity, and concentration of total protein in the BAL fluid (BALF) were determined. In the comparative studies, mice were intratracheally instilled with 50 μg per mouse of Nano-Ni or with the same molar concentration of Ni as Nano-Ni of either partially [O]-passivated Nano-Ni (Nano-Ni-P) or carbon-coated Nano-Ni (Nano-Ni-C). At day 3 post-exposure, BAL was performed and the above cellular and biochemical parameters in the BALF were analyzed. The MMP-2/9 protein levels and activities in the BALF and mouse lung tissues were also determined. Mouse lung tissues were also collected for H&E staining, and measurement of thiobarbituric acid reactive substances (TBARS) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in the genomic DNA. At day 42 post-exposure, mouse right lung tissues were collected for H&E and Trichrome stainings, and left lung tissues were collected to determine the hydroxyproline content.

RESULTS

Exposure of mice to Nano-Ni resulted in a dose-response increase in acute lung inflammation and injury reflected by increased neutrophil count, CXCL1/KC level, LDH activity, and concentration of total protein in the BALF. The time-response study showed that Nano-Ni-induced acute lung inflammation and injury appeared as early as day 1, peaked at day 3, and attenuated at day 7 post-instillation. Although the neutrophil count, CXCL1/KC level, LDH activity, and concentration of total protein in the BALF dramatically decreased over the time, their levels were still higher than those of the controls even at day 42 post-exposure. Based on the results of the dose- and time-response studies, we chose a dose of 50 µg per mouse of Nano-Ni, and day 3 post-exposure as short-term and day 42 post-exposure as long-term to compare the effects of Nano-Ni, Nano-Ni-P, and Nano-Ni-C on mouse lungs. At day 3 post-exposure, 50 μg per mouse of Nano-Ni caused acute lung inflammation and injury that were reflected by increased neutrophil count, CXCL1/KC level, LDH activity, concentration of total protein, and MMP-2/9 protein levels and activities in the BALF. Nano-Ni exposure also caused increased MMP-2/9 activities in the mouse lung tissues. Histologically, infiltration of large numbers of neutrophils and macrophages in the alveolar space and interstitial tissues was observed in mouse lungs exposed to Nano-Ni. Nano-Ni-P exposure caused similar acute lung inflammation and injury as Nano-Ni. However, exposure to Nano-Ni-C only caused mild acute lung inflammation and injury. At day 42 post-exposure, Nano-Ni caused extensive interstitial fibrosis and proliferation of interstitial cells with inflammatory cells infiltrating the alveolar septa and alveolar space. Lung fibrosis was also observed in Nano-Ni-P-exposed lungs, but to a much lesser degree. Only slight or no lung fibrosis was observed in Nano-Ni-C-exposed lungs. Nano-Ni and Nano-Ni-P, but not Nano-Ni-C, caused significantly elevated levels of TBARS in mouse lung tissues and 8-OHdG in mouse lung tissue genomic DNA, suggesting that Nano-Ni and Nano-Ni-P induce lipid peroxidation and oxidative DNA damage in mouse lung tissues, while Nano-Ni-C does not.

CONCLUSION

Our results demonstrate that short-term Nano-Ni exposure causes acute lung inflammation and injury, while long-term Nano-Ni exposure causes chronic lung inflammation and fibrosis. Surface modification of Nano-Ni alleviates Nano-Ni-induced pulmonary effects; partially passivated Nano-Ni causes similar effects as Nano-Ni, but the chronic inflammation and fibrosis were at a much lesser degree. Carbon coating significantly alleviates Nano-Ni-induced acute and chronic lung inflammation and injury.

Determination of Phosphorylated Histone H2AX in Nanoparticle-Induced Genotoxic Studies

DNA double-strand breaks (DSBs), one of the most severe lesions of DNA damage triggered by various genotoxic insults, can lead to chromosome change, genomic instability, and even tumorigenesis if not repaired efficiently. In response to DNA damage, histone H2AX molecules are rapidly phosphorylated at serine 139 near the site of DNA DSBs and form γ-H2AX foci. As an early important cellular event linked to DNA damage and repair, γ-H2AX is a highly sensitive biomarker for "monitoring" DNA damage and consequently is a useful tool in genetic toxicology screen. We and other researchers have used γ-H2AX as a marker to assess the potential genotoxic effects of some nanoparticles in vitro and in vivo. In this chapter, we describe several useful methods for γ-H2AX detection, which can be used to evaluate the potential genotoxic effects of nanoparticles.

Evaluation of Pulmonary Toxicity of Nanoparticles by Bronchoalveolar Lavage

Nanoparticles can enter the body via the lungs, the digestive tract, and the skin. The pulmonary effects of nanoparticles and the underlying mechanisms may be investigated by histopathological examination, immunostaining, bronchoalveolar lavage (BAL), and so on. BAL is a simple, fast, and inexpensive method that is commonly used to investigate the immune cells and acellular components in the lungs, which reflect the health state of the lungs. In this chapter, we describe the detailed procedures of performing BAL on mouse lungs. In a typical procedure, a catheter is inserted in the exposed trachea of a mouse, through which a phosphate-buffered saline (PBS) solution containing ethylenediaminetetraacetic acid (EDTA) is instilled into the lungs by a syringe. BAL fluid (BALF) is collected by gently retracting the instilled solution and massaging the thoracic cavity to maximize BALF retrieval and to minimize shearing forces. The type and number of differentiated immune cells in the BALF are analyzed, and the soluble factors such as total proteins, chemokines, and cytokines in the BALF are determined by protein assay, ELISA, etc.

Analysis of Nanomaterial Toxicity by Western Blot

Western blot is a routine biochemical technique for the immunodetection of proteins in cells and tissues exposed to nanomaterials (NMs). It is a sensitive method for protein analysis that involves the solubilization and separation of proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), transferring and immobilizing proteins onto a solid support, and targeted immunoprobing of a specific antigen. As a convenient and reliable research tool, the western blot plays an irreplaceable role in the era of proteomics together with mass spectrometry and protein chip. In this chapter we describe the detailed protocol for the entire process from sample preparation to quantitative measurement of target proteins.