Interplay of metabolic dysfunction-associated fatty liver disease and papillary thyroid carcinoma: insights from a Chinese cohort.

PURPOSE: Thyroid cancer is one of a set of extrahepatic cancers that closely linked to metabolic dysfunction-associated fatty liver disease (MAFLD). However, the connection between MAFLD and the characteristics of papillary thyroid cancer (PTC) remains unexplored. METHODS: Between Jan 2020 and Oct 2022, surgical cases of PTC patients were examined at the first Affiliated Hospital of Wenzhou Medical University. Clinical data extracted from the electronic medical system underwent a rigorous comparison between two groups, classified based on MAFLD criteria, using logistic regression analysis. RESULTS: In this study of 4,410 PTC patients, 18.3% had MAFLD. MAFLD emerged as a distinct risk factor for lymph node metastasis (OR = 1.230, 95% CI 1.018-1.487) in this cohort, especially in females (OR = 1.321, 95% CI 1.026-1.702) and those with BMI ≥ 23 kg/m2 (OR = 1.232, 95% CI 1.004-1.511). The presence of MAFLD was found to significantly elevate the risk of BRAF V600E mutation in both subgroups characterized by FIB-4 score ≥ 1.3 (OR = 1.968, 95% CI 1.107-3.496) and BMI < 23 kg/m2 (OR = 2.584, 95% CI 1.012-6.601). Moreover, among the subset of individuals without non-alcoholic fatty liver disease (NAFLD), it was noted that MAFLD considerably increased the likelihood of tumor multifocality (OR = 1.697, 95% CI 1.111-2.592). Nevertheless, MAFLD did not exhibit any correlation with increased tumor size, extra-thyroidal extension (ETE), or later TNM stage in PTC. CONCLUSION: In this cross-sectional study, we discovered a significant association between MAFLD and increased occurrences of lymph node metastasis. Furthermore, MAFLD was linked to a higher chance of BRAF V600E mutation and the presence of multiple tumors in certain subgroups.

Interventions to promote the implementation of pressure injury prevention measures in nursing homes: A scoping review.

AIMS: To identify studies and the content of the interventions that have facilitated the implementation of pressure injury (PI) prevention measures in nursing home settings. DESIGN AND METHOD: A scoping review methodology was employed. The author has carried out the following steps successively: Identified this scoping review's questions, retrieved potentially relevant studies, selected relevant studies, charted the data, summarised the results, and consulted with stakeholders from nursing homes in China. DATA SOURCES: Six electronic databases and three resources of grey literature-PubMed, CINAHL, Web of Science Core Collection, Embase, Cochrane Central Register of Controlled Trials, Psych INFO, Open Grey, MedNar, ProQuest Dissertations, and Theses Full Texts were searched from January 2002 through May 2022. RESULTS: Forty articles were included, among which the primary interventions were quality improvement, training and education, evidence-based practice, device-assisted PI prophylaxis, nursing protocols, and clinical decision support systems. Twenty-three outcome indicators were summarised in 40 articles, which included 10 outcome indicators, seven process indicators, and six structural indicators. Furthermore, only five articles reported barriers in the process of implementing interventions. CONCLUSION: The common interventions to promote the implementation of PI prevention measures in nursing homes are quality improvement, training, and education. Relatively limited research has been conducted on evidence-based practice, clinical decision support systems, device-assisted PI prophylaxis, and nursing protocols. In addition, there is a paucity of studies examining the impediments to implementing these measures and devising targeted solutions. Therefore, it is recommended that future studies include analysis and reporting of barriers and facilitators as part of the article to improve the sustainability of the intervention. IMPACT: This article reminds nursing home managers that they should realise the importance of implementation strategies between the best evidence of PI prevention and clinical practice. Also, this review provides the types, contents, and outcome indicators of these strategies for managers of nursing homes to consider what types of interventions to implement in their organisations. TRIAL AND PROTOCOL REGISTRATION: The protocol of this scoping review was published as an open-access article in June 2022 (Yang et al., 2022).

[Comparison of quantitative detection of BCR::ABL1 p210 transcript levels: a multicenter study].

Objective: To assess the capability of seven reference medical laboratories to detect BCR::ABL1 p210 transcription levels and to compare the results among those laboratories. Methods: The interlaboratory comparison was carried out in two stages. The samples were prepared by the reference laboratory. The quantitative values of BCR::ABL1 p210 of the comparison samples covered 0.001%-0.01%, 0.01%-0.1%, 0.1%-1%, 1%-10% and>10% in each stage. Real-time quantitative PCR (RT-PCR) and dPCR (digital PCR) were used to examine the samples. The conversion factor (CF) was calculated and validated for each laboratory. Results: In the RT-PCR comparison, one laboratory was failed to detect BCR::ABL1 p210 in fourteen samples at the first stage. The results of the other six laboratories were qualified with the bias <±1.2 folds (-0.133-0.338) and 95% limits of agreement within ±5 folds (upper limit 0.147-0.785, lower limit -0.770--0.109), and the corresponding CF values were calculated and validated. In the dPCR comparison, one laboratory did not report results at the second stage. The results of the other six laboratories were qualified with the bias <±1.2 folds (-0.026-0.267) and 95% limits of agreement within±5 folds (upper limit 0.084-0.991, lower limit -0.669--0.135), and the corresponding CF values were calculated and validated. The samples with BCR::ABL1 p210 quantitative values of 0.01%-0.1%, 0.1%-1%, 1%-10% and >10% could be detected by both RT-PCR and qPCR. When the quantitative value of BCR::ABL1 p210 was 0.001%-0.01%, the detection rate of dPCR was higher than that of RT-PCR (85.56% vs. 68.00%). Conclusions: A good consistency is present among various laboratories. The quantitative value of BCR::ABL1 p210 is comparable among laboratories as shown by the CF value conversion. For quantitative detection of BCR::ABL1 p210 deep molecular reaction, dPCR has a higher positive detection rate and more advantages than RT-PCR. To ensure the accuracy and reproducibility of the BCR::ABL1 p210 test, it is imperative for every laboratory to enhance their daily quality control practices.

[Bibliometric and visual analysis of neurological damage caused by electrical welding operations].

Objective: To analyze and summarize the trends and hot spots in the field of neurological damage caused by electric welding operations, and to provide ideas for new researches by searching the domestic and international literature. Methods: In December 2022, using Web of Science Citation Index (Web of Science), China Journal Full-Text Database (CNKI) and Wanfang Database as search databases, literature search was conducted on the Chinese and English search terms related to eletrical welding operations and neurological damage. The bibliometric analysis software VOSviewer 1.6.18 and CiteSpace 6.1.6 were used to visualize the publication year, publication quantity, country, research institution and key words of the literature. Results: A total of 309 articles (112 in Chinese and 197 in English) were included in this study. The first domestic and international papers were published in 1976 and 1994 respectively, and the number of papers reached the peak in 2006 and 2018, and then showed a downward trend to varying degrees. In China, Shandong First Medical University (including Shandong Institute of Occupational Health and Occupational Disease Prevention and Shandong Academy of Medical Sciences) and Wuhan University of Science and Technology had the largest number of publications. The 309 articles were from 52 Chinese journals and 86 English journals. The co-occurrence analysis of key words showed that the domestic research mainly focused on eletrical welding operation, welding workers, neurobehavioral function and manganese, and the nervous system damage caused by manganese in welding smoke was the field of international attention. Long term exposure, risk, and performance were key buzzwords in the field. Conclusion: The research focus in the field of nervous system damage caused by electric welding operation has an obvious trend of time evolution, gradually transiting from clinical manifestations to its toxic mechanism and early biomarkers.

[Analysis of Dimethyltryptamine in Captured Suspicious Substances：Three Case Reports].

ABSTRACT: Abstract.

[Identification of New Psychoactive Tryptamines 4-OH-MET and 4-AcO-DMT Using High Resolution Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy].

ABSTRACT: Objective To detect the uncontrolled new psychoactive tryptamines involved in drug-related cases with high resolution mass spectrometry and nuclear magnetic resonance spectroscopy. Methods White and brown powder obtained in actual cases were extracted and analyzed by gas chromatography-quadrupole time-of-flight mass spectrometry （GC-QTOF-MS）, ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry （UPLC-LTQ-Orbitrap MS） and 1H-nuclear magnetic resonance spectroscopy （1H-NMR）. Results After detection by GC-QTOF-MS, the components of white powder showed main characteristic fragment ion peaks at m/z 218.141 0 （molecular ion peak）, 72.080 6 （base peak）, etc. After detection by UPLC-LTQ-Orbitrap MS, its protonated molecular ion was m/z 219.149 4. The main ions in the secondary mass spectrum under the collision-induced dissociation （CID） mode were m/z 160.076 3 and 72.080 8. After detection by GC-QTOF-MS, the components of brown powder showed main characteristic fragment ion peaks at m/z 246.135 7 （molecular ion peak）, 58.065 1 （base peak）, etc. After detection by UPLC-LTQ-Orbitrap MS, its protonated molecular ion was m/z 247.145 0. The main ions in the secondary mass spectrum under CID mode were m/z 202.087 1, 160.076 3 and 134.060 5. NIST 17 library retrieval and 1H-NMR confirmed that the white powder and brown powder contained new psychoactive tryptamines 4-OH-MET and 4-AcO-DMT, respectively. Conclusion GC-QTOF-MS, UPLC-LTQ-Orbitrap MS and 1H-NMR can be used together to identify unknown new psychoactive substances.

[Analysis of the first national public health practice skills competition among college students].

To analyze the difficulty, distinction and result of the first national public health practice skills competition among college students, it showed the general situation of this competition, and discussed the present situation, problems and countermeasures of skills training for students majoring in preventive medicine. Based on such competition, educators can promote teaching reform and post competency training.

Enhancement in speed and responsivity of uni-traveling carrier photodiodes with GaAs0.5Sb0.5/In0.53Ga0.47As type-II hybrid absorbers.

We demonstrate a top-illuminated high-speed uni-traveling carrier photodiode (UTC-PD) with a novel design in the p-type absorber, which can effectively shorten the photon absorption depth at telecommunication wavelengths (1.31~1.55 µm) and further enhance the bandwidth-efficiency product of UTC-PD. In our proposed new UTC-PD structure, the p-type In0.53Ga0.47As absorption layer is replaced by the type-II GaAs0.5Sb0.5 (p)/In0.53Ga0.47As (i) hybrid absorber. Due to the narrowing of the bandgap and enhancement of the photo-absorption process at the type-II interface between the GaAs0.5Sb0.5 and In0.53Ga0.47As layers, our device shows an over 16.7% improvement in the responsivity compared with that of UTC-PD with the same thickness of pure In0.53Ga0.47As absorber (0.7 µm) and a zero optical coupling loss. Our demonstrated device with a simple top-illuminated structure offers a large active mesa (25 µm), a wide optical-to-electrical (O-E) bandwidth (33 GHz), a high responsivity (0.7 A/W), and a high saturation current (>5 mA) under 1.31 µm optical wavelength. These promising results suggest that our proposed PD structure can fundamentally overcome the trade-off among bandwidth, efficiency, and device active diameter of high-speed PDs.

Phenotypic analysis of atopic dermatitis in children aged 1-12 months: elaboration of novel diagnostic criteria for infants in China and estimation of prevalence.

BACKGROUND: Atopic dermatitis (AD) is the most common skin disorder in infancy. However, the diagnosis and definite significance of infantile AD remains a debated issue. OBJECTIVE: To analyse the phenotypes of AD in infancy, to establish diagnostic criteria and to estimate the prevalence of this condition in China. METHODS: This is a multicentric study, in which 12 locations were chosen from different metropolitan areas of China. Following careful and complete history-taking and skin examination, the definite diagnosis of AD was made and the severity based on the SCORAD index was determined by local experienced dermatologists. Based on the detailed phenotyping, the major and representative clinical features of infantile AD were selected to establish the diagnostic criteria and evaluate their diagnostic efficacy. RESULTS: A total of 5967 infants were included in this study. The overall point prevalence of AD was 30.48%. The infantile AD developed as early as at the second month of life, and its incidence peaked in the third month of life at 40.81%. The proportion of mild, moderate and severe AD was 67.40%, 30.57% and 2.03%, respectively. The most commonly seen manifestations in the infantile AD were facial dermatitis (72.07%), xerosis (42.72%) and scalp dermatitis (27.93%). We established the novel diagnostic criteria of infants, which included: (i) onset after 2 weeks of birth; (ii) pruritus and/or irritability and sleeplessness comparable with lesions; and (iii) all two items above with one of the following items can reach a diagnosis of AD: (i) eczematous lesions distributed on cheeks and/or scalp and/or extensor limbs, and (ii) eczematous lesions on any other parts of body accompanied by xerosis. CONCLUSIONS: In China, the prevalence of AD in infancy is 30.48% according to clinical diagnosis of dermatologists. The novel Chinese diagnostic criteria for AD in infants show a higher sensitivity and comparable specificity.

Factors associated with overall survival and relief of dysphagia in advanced esophageal cancer patients after 125I seed-loaded stent placement: a multicenter retrospective analysis.

Iodine-125 (125I) seed-loaded stent placement has served as an effective palliation for malignant esophageal strictures in China. We performed a retrospective study to identify the prognostic factors of this irradiation stent placement in advanced esophageal cancer patients. A total of 201 patients who underwent 125I seed-loaded stent placement were included in this study from June 2012 to March 2016 at five hospitals in China. The Cox regression models adjusted for stratification factors were used, and a stepwise multivariate analysis was performed to predict the overall survival and relief of dysphagia on the basis of pretreatment clinical characteristics, respectively. Three independent prognostic factors were identified for overall survival: histopathological subtype (squamous cell carcinoma vs. adenocarcinoma, hazard ratio [HR] 1.45, 95% confidence interval [CI95%]: 1.01-2.09, P = 0.046), serum total protein (≥66 g/L vs. <66 g/L, HR 0.61, CI95%: 0.48-0.59, P = 0.023), and performance status (<2 vs. ≥2, HR 1.57, CI95%: 1.09-2.08, P = 0.013). Four factors were significantly associated with the relief of dysphagia: T stage (T3 vs. T4, P = 0.003), tumor location (superior vs. inferior, P = 0.049), tumor-node-metastasis classification (IV vs. II, P = 0.025), and age (≥71 years vs. <71 years, P = 0.029). Prognostic factors identified from this analysis can be used to aid clinical decision-making and design future clinical trials.

Liraglutide ameliorates palmitate-induced insulin resistance through inhibiting the IRS-1 serine phosphorylation in mouse skeletal muscle cells.

OBJECTIVE: A reduction in insulin-stimulated glucose uptake in skeletal muscles is a characteristic of insulin resistance and type 2 diabetes mellitus (T2DM). The glucagon-like peptide (GLP)-1 agonist liraglutide can reduce blood glucose levels in individuals with T2DM. However, its effect on insulin-induced glucose metabolism in the skeletal muscle of insulin resistance is unknown. We investigated the effects and action mechanisms of liraglutide on insulin resistance (IR) in the skeletal muscle cells treatment with palmitic acid (PA). METHODS: The cell-surface GLUT4myc levels were determined by an antibody-coupled colorimetric assay. The phosphorylation levels of Akt, PI3K(p85α), AS160, IRS1, IKK, and JNK were determined by western blotting. The quantifications of mRNA levels of TNFα, IL-1ß, and IL-6 were determined by real-time PCR. Analysis of variance was used for data analysis. RESULTS: PA elevated not only phosphorylation of JNK, IRS1 serines, and IKKα/ß, but also the expression of IL-6, TNFα and IL-1ß in C2C12-GLUT4myc cells. PA can reduce phosphorylation of IRS1 tyrosine. These effects of PA were reversed by liraglutide. In addition, liraglutide can reverse PA-decreased insulin-stimulated cell-surface GLUT4 levels, Akt, PI3K(p85α), and AS160 phosphorylation. CONCLUSIONS: Liraglutide can enhance insulin-induced GLUT4 translocation by inhibiting IRS1 serine phosphorylation in PA-treated muscle cells.

[Clinical evaluation of in-plane ultrasound-guided thoracic paravertebral block using laterally intercostal approach].

OBJECTIVE: To evaluate the feasibility and success rate of in-plane ultrasound-guided paravertebral block using laterally intercostal approach. METHODS: In the study, 27 patients undergoing elective thoracic surgery were selected to do paravertebral block preoperatively. The fifth intercostal space was scanned by ultrasound probe which was placed along the long axis of the rib and 8 cm lateral to the midline of the spine. The needle was advanced in increments aiming at the space between the internal and innermost intercostal muscles. Once the space between the muscles was achieved, 20 mL of 0.5% (mass fraction) ropivacaine was injected and a catheter was inserted. Whether the tip of catheter was in right place was evaluated by ultrasound image. The block dermatomes of cold sensation were recorded 10, 20 and 30 min after the bolus drug was given. Then 0.2% ropivacaine was infused with 6 mL/h via the catheter by an analgesia pump postoperatively. The block dermatomes of cold sensation and pain score were recorded 1, 6, 24 and 48 h postoperatively. RESULTS: The first attempt success rate of catheteration was 81.48% (22/27); the tips of catheter were proved in right places after the second or third attempt in 5 patients. The median numbers of the block dermatomes 10, 20 and 30 min after the bolus drug was given were 2, 3, 4; the median numbers of block dermatomes were 5, 5, 5, 4, and of pain score were 1, 1, 2, 2 at 1, 6, 24, 48 h postoperatively; no case of bilateral block, pneumothorax or vessel puncture occurred. CONCLUSION: Thoracic paravertebral block using laterally intercostal approach is feasible, which has high success rate of block and low rate of complications.

[Therapeutic effect of miR-489 in a mouse model of silica-induced matured pulmonary fibrosis].

Objective: To explore the potential therapeutic role of miR-489 in silica-induced pulmonary fibrosis mouse models. Methods: A total of 32 C57BL/6 male mice were randomly divided into four groups: saline, silica, silica plus miRNA control and silica plus miR-489 agomir (n=8 in each group) . The mice were instilled with silica particles suspended in saline or sterile saline intratracheally. Subsequently, miR-489 agomir or miRNA control was injected via the tail vein into each mouse at days 28, 35, 42 and 49, the miR-489 levels, histological examination, collagen deposition, fibrotic biomarkers (E-cadherin, α-SMA, Vimentin, Fibronectin) and transforming growth factor-ß(1) (TGF-ß(1)) protein levels in mouse lung tissues were measured. Results: miR-489 levels in silica plus miR-489 group were significantly increased in lung tissues compared with silica plus miRNA control group (P<0.05) . Histological examination showed attenuated inflammation, less severe fibrotic foci and less destruction of alveolar architecture in the silica plus miR-489 group. Additionally, both the severity and distribution of lung lesions were ameliorated in silica plus miR-489 group compared with the silica plus miRNA control group (P<0.05) . The collagen deposition and hydroxyproline levels in silica plus miR-489 group were significantly decreased compared with the silica plus miRNA control group (P<0.05) . These changes were supported by decreased protein levels of α-SMA, Vimentin, Fibronectin, TGF-ß1 along with increased protein levels of E-cadherin in silica plus miR-489 group (P<0.05) . Conclusion: Our data indicate that the upregulation of miR-489 has potential therapeutic role in silica-induced pulmonary fibrosis in vivo, which may be associated with the depression of TGF-ß1 release.

Lentiginous phenotypes caused by diverse pathogenic genes (SASH1 and PTPN11): clinical and molecular discrimination.

Pathogenic mutations in genes (SASH1 and PTPN11) can cause a rare genetic disorder associated with pigmentation defects and the well-known LEOPARD syndrome, respectively. Both conditions presented with lentiginous phenotypes. The aim of this study was to arrive at definite diagnoses of three Chinese boys with clinically suspected lentigines-related syndromes. ADAR1, ABCB6, SASH1 and PTPN11 were candidate genes for mutational screening. Sanger sequencing was performed to identify the mutations, whereas bioinformatic analysis was used to predict the pathogenicity of novel missense mutations. Two novel mutations c.1537A>C (p.Ser513Arg) and 1527_1530dupAAGT (p.Leu511Lysfs*21) in SASH1 and a common p.Thr468Met mutation in PTPN11 were detected in three pediatric patients with lentiginous phenotypes, respectively. Comparisons between clinical presentations showed that SASH1-related phenotypes can exhibit hyper- and hypopigmentation on the trunk and extremities, similar to dyschromatosis, while scattered café au-lait spots usually appeared in PTPN11-related LEOPARD syndrome. Furthermore, the similarity in the clinical presentations of Peutz-Jeghers syndrome, Laugier-Hunziker syndrome, xeroderma pigmentosum, neurofibromatosis type I, suggesting that these conditions should be added into the differential diagnoses of lentiginous phenotypes.

Probing the energy levels of perovskite solar cells via Kelvin probe and UV ambient pressure photoemission spectroscopy.

The field of organo-lead halide perovskite solar cells has been rapidly growing since their discovery in 2009. State of the art devices are now achieving efficiencies comparable to much older technologies like silicon, while utilising simple manufacturing processes and starting materials. A key parameter to consider when optimising solar cell devices or when designing new materials is the position and effects of the energy levels in the materials. We present here a comprehensive study of the energy levels present in a common structure of perovskite solar cell using an advanced macroscopic Kelvin probe and UV air photoemission setup. By constructing a detailed map of the energy levels in the system we are able to predict the importance of each layer to the open circuit voltage of the solar cell, which we then back up through measurements of the surface photovoltage of the cell under white illumination. Our results demonstrate the effectiveness of air photoemission and Kelvin probe contact potential difference measurements as a method of identifying the factors contributing to the open circuit voltage in a solar cell, as well as being an excellent way of probing the physics of new materials.

Novel MBTPS2 missense mutation causes a keratosis follicularis spinulosa decalvans phenotype: mutation update and review of the literature.

Keratosis follicularis spinulosa decalvans (KFSD) is an X-linked condition characterized by keratotic follicular papules and progressive alopecia, which is caused by mutations in the MBTPS2 gene. We carried out a genetic study on a child who was suspected clinically to have KFSD. Sanger sequencing was performed to detect mutations in the entire coding region of MBTPS2. A novel missense mutation (c.599C>T) was identified in the patient, confirming a diagnosis of KFSD. We reviewed related cases with MBTPS2 mutations for evidence of genotype-phenotype correlations.

Atopy patch test with house dust mite in Chinese patients with atopic dermatitis.

BACKGROUND: The atopy patch test (APT) has been defined as an important tool in the diagnosis of cutaneous hypersensitivity caused by house dust mites in atopic dermatitis (AD). OBJECTIVE: The aim of this study was to evaluate the diagnostic value of the APT to mite allergens by comparing its positive results with those of the skin prick test (SPT) and serum specific IgE test in Chinese AD patients. METHODS: The APT, SPT and serum specific IgE test with Dermatophagoiodes pteronyssinus and Dermatophagoides farina were performed on a total of 120 patients with atopic dermatitis. RESULTS: Overall, 37.5% of the patients showed a positive APT reaction to mite allergens. A statistically significant association was observed between positive APT results and air-exposed eczema pattern. The positive APT results were not significantly associated with SCORAD scores and accompanied atopic respiratory disorders in AD patients. A higher frequency of APT positive reactions to mite allergens was observed in adolescent and adult patients. There was no significant difference in APT positivity between extrinsic patients (40.7%) and intrinsic patients (27.6%). CONCLUSION: This study identified house dust mite induced cutaneous hypersensitivity in Chinese patients with AD by APT, especially in air-exposed distribution patterns or adolescent and adult patients. Both intrinsic and extrinsic AD patients showed positive APT reactions to house dust mite.

Mutations in the mevalonate pathway genes in Chinese patients with porokeratosis.

BACKGROUND: Porokeratosis (PK, MIM 175800) is a chronic autosomal dominant cutaneous keratinization disorder, which has a wide variety of clinical manifestations. OBJECTIVES: We analysed the molecular basis of 10 families and 12 sporadic cases with different subtypes of porokeratosis in the Chinese population. METHODS: Genomic DNA was extracted from peripheral blood samples. Mutation screening was performed by direct sequencing of exons and flanking intron-exon boundaries for the entire coding region of four mevalonate pathway genes and SLC17A9 gene. RESULTS: We detected three novel mutations and seven previously described mutations by direct sequence analysis of the PCR products. Mutations p.Phe249Ser and p.Asn292Ser in mevalonate decarboxylase (MVD) were the most common mutations in this PK cohort; their presence was 27.3% and 13.6% respectively. CONCLUSIONS: This study extended the mutation spectrum of PK in the Chinese Han population and provided further evidence for the genetic basis of PK. We first identified MVD simultaneously responsible for porokeratosis palmaris et plantaris disseminate development and confirmed the genotype-phenotype correlations.

Annexin A5 promotes macrophage activation and contributes to pulmonary fibrosis induced by silica particles.

OBJECTIVE: To investigate the contributions and underlying molecular mechanisms of annexin A5 toward silica-induced pulmonary fibrosis. METHODS: Male C57BL/6 mice were randomly divided into three groups and instilled intratracheally with silica, saline, or air. Mice were euthanized at 3, 7, 14, or 28 days following treatment. Annexin A5 levels in serum and lung tissues were detected by enzyme-linked immunosorbant assay (ELISA) assays or Western blots. The association of annexin A5 levels with silica-induced lung fibrosis was further investigated in the macrophage cell line, RAW264.7. Following exposure of these cells to silica at a concentration of 200 µg/ml for 6 or 12 h, the expression levels of transforming growth factor ß1 (TGF-ß1), interleukin 1α (IL-1α), Fas ligand (FasL), and their downstream targets were evaluated by Western blots. Furthermore, annexin A5 and FasL were knocked down by small interfering ribonucleic acid (siRNA) and TGF-ß1 secretion into the cell culture medium was measured by ELISA assays or Western blots. RESULTS: Mice treated with silica demonstrated lung fibrosis at 28 days following exposure, whereas, in controls, only mild and transient inflammation was evident at day 3 and day 7 postinstillation and was not present at day 14. Furthermore, silica-exposed mice exhibited significantly (p < 0.05) elevated levels of annexin A5 in serum and lung tissues, relative to control groups. Consistent with these findings, silica exposure of RAW264.7 cells for 6 or 12 h, led to an annexin A5-dependent increase in the expression levels of TGF-ß1, IL-1α, FasL, and their downstream target molecules. These silica-induced changes were reversed by siRNA-mediated knockdown of annexin A5, but downregulation of FasL led to increased annexin A5 expression and reduced levels of TGF-ß1, IL-1α, and FasL downstream target molecules. CONCLUSIONS: These findings define a role of annexin A5 in promoting macrophage activation via Fas/FasL pathways in silica-induced lung fibrosis.