1.Olfactory Receptors Expressed in The Intestine and Their Functions
Pei-Wen YANG ; Meng-Meng YUAN ; Ying ZHOU ; Peng LI ; Gui-Hong QI ; Ying YANG ; Zhong-Yi MAO ; Meng-Sha ZHOU ; Xiao-Shuang MAO ; Jian-Ping XIE ; Yi-Nan YANG ; Shi-Hao SUN
Progress in Biochemistry and Biophysics 2026;53(3):534-549
Olfactory receptors (ORs) form the largest superfamily of G protein-coupled receptors (GPCRs). Traditionally recognized for their role in the nasal olfactory epithelium, where they mediate the sense of smell, accumulating evidence has firmly established their ectopic expression in non-olfactory tissues, including the intestine, lungs, and kidneys. The intestine, as the primary site for nutrient digestion and absorption, harbors a highly complex chemical environment. To adapt to this environment, the gut employs a sophisticated network of “chemosensors” to monitor luminal contents and maintain homeostasis. Among these sensors, intestinal ORs have emerged as crucial functional components, serving as a molecular bridge that connects environmental chemical signals—such as food-derived odorants—to specific physiological responses. This discovery has significantly deepened our understanding of how dietary flavors and compounds influence intestinal physiology at the molecular level. This review systematically summarizes the expression profiles, ligand classification, and biological functions of ORs within the gastrointestinal tract. Studies indicate that intestinal ORs exhibit distinct spatial distribution patterns across different gut segments and display cell-type specificity, particularly within enterocytes and enteroendocrine cells. These receptors function as versatile sensors capable of recognizing a wide variety of ligands, including exogenous dietary components, gut microbiota metabolites such as short-chain fatty acids, and endogenous small molecules like azelaic acid. Upon activation by specific ligands, intestinal ORs trigger intracellular signaling cascades, primarily involving the AC-cAMP-PKA pathway or calcium influx channels. A major focus of this review is to elucidate the molecular mechanisms by which these receptors regulate the secretion of gut hormones. Activation of specific ORs in enteroendocrine cells has been shown to stimulate the release of hormones such as glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and serotonin (5-HT), thereby modulating systemic energy metabolism, glucose homeostasis, and gastrointestinal motility. Furthermore, the review addresses the critical roles of ORs in immune regulation and pathology. Evidence suggests that specific ORs contribute to the maintenance of intestinal immune homeostasis and may offer protection against inflammation. Beyond their involvement in inflammatory responses, ORs such as Olfr78 have been shown to regulate the differentiation and function of intestinal endocrine cells. Similarly, Olfr544 has been demonstrated to alleviate intestinal inflammation by remodeling the gut microbiome and metabolome. These findings collectively suggest that specific ORs hold promise as therapeutic targets for mitigating intestinal inflammation and maintaining gut homeostasis. Additionally, the review explores the emerging role of ORs in cancer. Although OR expression is often downregulated in tumor tissues compared to normal mucosa, activation of specific ORs by certain ligands can inhibit tumor cell proliferation and migration and induce apoptosis via pathways such as MEK/ERK and p38 MAPK. Conversely, other receptors, such as OR7C1, may serve as biomarkers for cancer-initiating cells. In conclusion, intestinal ORs represent a vital component of the gut’s sensory network. The review also discusses the translational potential of these findings. By elucidating the precise pairing relationships between dietary components and specific ORs, novel therapeutic strategies could be developed. Intestinal ORs may thus emerge as promising targets for nutritional and pharmacological interventions in metabolic diseases, inflammatory bowel diseases, and malignancies.
2.Causal relationship between age-related macular degeneration and deep vein thrombosis:analysis based on genome-wide association study data
Hongtao LIU ; Xin WU ; Xinyu JIANG ; Fei SHA ; Qi AN ; Gaobiao LI
Chinese Journal of Tissue Engineering Research 2026;30(6):1602-1608
BACKGROUND:Age-related macular degeneration and deep vein thrombosis may share common pathophysiological mechanisms,but there is a lack of direct evidence regarding their relationship.Traditional studies are confounded by confounding factors and reverse causation.OBJECTIVE:To investigate the causal relationship between age-related macular degeneration and deep vein thrombosis based on Mendelian randomization design.METHODS:Through a two-way Mendelian randomization analysis,single nucleotide polymorphisms of exposure and outcomes were obtained from publicly available genome-wide association studies,with deep vein thrombosis data from the FinnGen database in a European population with a sample size of 363 612 and 1 048 575 single nucleotide polymorphisms.In addition,we obtained data on age-related macular degeneration from the IEUOpenGWAS project,also from a European population sample of 105 248 cases covering 11 304 110 single nucleotide polymorphisms.In R4.4.1,we used the TwoSampleMR package(version 0.6.8)to explore the causal effects of exposure factors on outcomes.At the same time,we also conducted a sensitivity analysis via MR-Egger regression,weighted median,weighted model and simple model methods to ensure that the assessment results were robust and reliable.In addition,we used the"heterogeneity"function to test for heterogeneity,and the"horizontal pleiotropy"function and the MR-PRESSO test to further assess horizontal pleotropy.The Cochran's Q test was used to determine whether there was statistical heterogeneity between single nucleotide polymorphisms,and the leave-one-out method was used to assess whether single nucleotide polymorphisms would significantly interfere with Mendelian randomization analysis.Funnel plots were drawn to assess the potential bias of single nucleotide polymorphisms.Forest plots were plotted to show the effect estimates of single nucleotide polymorphisms on exposure and outcomes,and their confidence intervals were plotted.Scatter plots were plotted to evaluate the relationship between the potency of single nucleotide polymorphisms and their causal effect size on outcome estimates.RESULTS AND CONCLUSION:Both forward and reverse studies showed that there was no causal association between age-related macular degeneration and the occurrence of deep vein thrombosis(P>0.05).Sensitivity analysis showed that the main analysis results were reliable and robust,with no outliers,heterogeneity,and horizontal pleiotropy,and no single nucleotide polymorphism significantly affected the overall effect estimate.Although it is based on European population data,it has methodological reference value for Chinese biomedical research on complex disease associations.In this field,China can carry out multi-center large-sample studies,accurately analyze the internal links between Chinese population-related diseases,and provide a basis for prevention and treatment strategies and clinical practice.
3.Causal relationship between age-related macular degeneration and deep vein thrombosis:analysis based on genome-wide association study data
Hongtao LIU ; Xin WU ; Xinyu JIANG ; Fei SHA ; Qi AN ; Gaobiao LI
Chinese Journal of Tissue Engineering Research 2026;30(6):1602-1608
BACKGROUND:Age-related macular degeneration and deep vein thrombosis may share common pathophysiological mechanisms,but there is a lack of direct evidence regarding their relationship.Traditional studies are confounded by confounding factors and reverse causation.OBJECTIVE:To investigate the causal relationship between age-related macular degeneration and deep vein thrombosis based on Mendelian randomization design.METHODS:Through a two-way Mendelian randomization analysis,single nucleotide polymorphisms of exposure and outcomes were obtained from publicly available genome-wide association studies,with deep vein thrombosis data from the FinnGen database in a European population with a sample size of 363 612 and 1 048 575 single nucleotide polymorphisms.In addition,we obtained data on age-related macular degeneration from the IEUOpenGWAS project,also from a European population sample of 105 248 cases covering 11 304 110 single nucleotide polymorphisms.In R4.4.1,we used the TwoSampleMR package(version 0.6.8)to explore the causal effects of exposure factors on outcomes.At the same time,we also conducted a sensitivity analysis via MR-Egger regression,weighted median,weighted model and simple model methods to ensure that the assessment results were robust and reliable.In addition,we used the"heterogeneity"function to test for heterogeneity,and the"horizontal pleiotropy"function and the MR-PRESSO test to further assess horizontal pleotropy.The Cochran's Q test was used to determine whether there was statistical heterogeneity between single nucleotide polymorphisms,and the leave-one-out method was used to assess whether single nucleotide polymorphisms would significantly interfere with Mendelian randomization analysis.Funnel plots were drawn to assess the potential bias of single nucleotide polymorphisms.Forest plots were plotted to show the effect estimates of single nucleotide polymorphisms on exposure and outcomes,and their confidence intervals were plotted.Scatter plots were plotted to evaluate the relationship between the potency of single nucleotide polymorphisms and their causal effect size on outcome estimates.RESULTS AND CONCLUSION:Both forward and reverse studies showed that there was no causal association between age-related macular degeneration and the occurrence of deep vein thrombosis(P>0.05).Sensitivity analysis showed that the main analysis results were reliable and robust,with no outliers,heterogeneity,and horizontal pleiotropy,and no single nucleotide polymorphism significantly affected the overall effect estimate.Although it is based on European population data,it has methodological reference value for Chinese biomedical research on complex disease associations.In this field,China can carry out multi-center large-sample studies,accurately analyze the internal links between Chinese population-related diseases,and provide a basis for prevention and treatment strategies and clinical practice.
4.A Review and Evaluation of Integrated Disease and Syndrome Animal Models for Hemorrhoids in Traditional Chinese and Western Medicine
Yu BU ; Jinting HOU ; Yuanyuan LI ; Jingtao SHA ; Chenlu XIE ; Wengang WANG ; Xingwei SUN
Laboratory Animal and Comparative Medicine 2026;46(3):357-366
Hemorrhoids are common anorectal diseases with complex pathogenesis, and there is still a lack of ideal experimental animal models for research on their prevention and treatment. In this paper, Chinese and English databases are searched with the keywords "hemorrhoids" and "animal model", and 36 relevant studies are finally included. The shortcomings of existing hemorrhoid animal models in integrating the clinical disease and syndrome characteristics of traditional Chinese and Western medicine are systematically analyzed, and the consistency of various models with clinical practice is evaluated. The studies are divided into four categories according to modeling methods: chemical modeling, physical modeling, biological modeling, and combined modeling. The clinical consistency of modeling is evaluated in combination with the diagnostic points of hemorrhoids in traditional Chinese and Western medicine. The results show that there are significant differences in the reproduction of clinical indicators by different modeling methods. According to clinical consistency, the models can be divided into three grades: high-consistency models are mainly based on combined modeling methods (such as induction by carrageenan combined with norepinephrine hydrochloride), which can more comprehensively simulate core pathological changes such as venous congestion and local inflammation; moderate-consistency models adopt single chemical or physical intervention (such as local inflammation induced by croton oil or vein ligation), which can only reproduce part of the pathological process; low-consistency models mostly adopt direct stimulation, with limited research value for pathological characteristics. Existing animal models have obvious advantages in replicating Western medical structural lesions of hemorrhoids, but they still have obvious defects in simulating the chronic disease course and stably reproducing the characteristics of traditional Chinese medicine syndromes, and a unified standard has not yet been formed for the traditional Chinese medicine evaluation system of models. In conclusion, it is still necessary to further explore the construction of high-quality integrated disease and syndrome animal models for hemorrhoids in traditional Chinese and Western medicine. Future research should integrate the theories of traditional Chinese and Western medicine, adopt multi-factor chronic modeling strategies, and establish a standardized comprehensive evaluation system covering macroscopic signs and microscopic indicators. This paper provides a reference for constructing standardized integrated disease and syndrome animal models of hemorrhoids that conform to the pathological changes of Western medicine and take into account the characteristics of traditional Chinese medicine syndromes, with the aim of providing more effective experimental tools for research on the pathogenesis of hemorrhoids and their integrated prevention and treatment with traditional Chinese and Western medicine.
5.Association between brain and muscle Arnt like protein 1 gene polymorphisms and ambulatory blood pressure among college students
Chinese Journal of School Health 2026;47(6):864-868
Objective:
To investigate the association between brain and muscle Arnt like protein 1( BMAL 1) gene and ambulatory blood pressure (ABP) parameters in college students, and to explore the influence of the interaction between the gene and weight status on the ABP levels, so as to provide reference for early prevention of chronic cardiovascular diseases related to hypertension.
Methods:
During September 2022 to June 2024, a total of 510 college students were recruited from a university in Changsha, China for on site questionnaire investigation, physical examination, ABP monitoring and genotyping testing. Multiple linear regression method was used to explore the association between the BMAL 1 gene and ABP indicators. An interaction term was included in the general linear model of multiple linear regression to analyze the interactive effects of BMAL 1 gene polymorphisms and weight status on ABP levels.
Results:
The prevalence of abnormal 24 hour blood pressure, abnormal daytime blood pressure, and abnormal nighttime blood pressure were 3.3%, 3.1%, and 3.9%, respectively. Multiple linear regression analysis showed that the BMAL 1/rs7950226 polymorphism was positively correlated with the 24 hour diastolic blood pressure(DBP) and the daytime DBP level after adjusting for gender, age, and body mass index( β =0.87,0.99, both P <0.05). Also, interaction between BMAL 1/ rs 11022775 and weight status on the nighttime DBP level ( P interaction =0.03) was found. The CC genotype carriers had significantly higher nighttime DBP level ( β =3.52, P <0.05) among overweight/obesity college students, but no differences in nocturnal DBP levels were observed between CC genotype carriers and TT+CT genotype carriers among college students with normal body weight( P > 0.05).
Conclusions
The rs 7950226 polymorphism is associated with 24 hours DBP and daytime DBP levels. Significant interaction between rs 11022775 with weight status on the nighttime DBP level is found among college students.
6.Clinical and Immunological Characteristics of Elderly Onset Rheumatoid Arthritis
Zhengfang LI ; Chanyuan WU ; Mengsi MA ; Tingting LI ; Xue WU ; Xinyan MENG ; Sha ZHANG ; Lijun WU
Medical Journal of Peking Union Medical College Hospital 2025;16(1):59-64
To investigate the clinical features and peripheral blood immune cell subsets ofelderly (≥60 years old) onset rheumatoid arthritis (EORA) patients. The patients with rheumatoid arthritis (RA) who were hospitalized in the Department of Rheumatology and Immunology of the People's Hospital of Xinjiang Uygur Autonomous Region from March 2023 to December 2023 were selected as the study objects. The demographic data, clinical characteristics, extra-articular manifestations and laboratory examination results of the patients were collected. The patients were divided into EORA group and young adult (< 60 years old)onset rheumatoid arthritis (YORA) group, and the clinical features and peripheral blood immunological indexes of the two groups were compared. A total of 187 RA patients with an average age of (62.1±12.0) years were enrolled, including 89 patients in the EORA group and 98 patients in the YORA group. Compared with YORA group, EORA group had a higher proportion of male patients(39.3% Compared with YORA, EORA has higher male proportion, joint disease degree and disease activity. EORA is prone to interstitial lung disease, anemia and high inflammation, and the level of peripheral blood NK cells is higher.
7.Prognostic Significance of KMT2D Gene Mutation and Its Co-mutated Genes in Patients with Diffuse Large B-Cell Lymphoma
Mutibaier·MIJITI ; Xiaolong QI ; Renaguli·ABULAITI ; Wenxin TIAN ; Sha LIU ; Weiyuan MA ; Zengsheng WANG ; Li AN ; Min MAO ; Muhebaier·ABUDUER ; Yan LI
Cancer Research on Prevention and Treatment 2025;52(2):127-132
Objective To explore the clinical characteristics of patients with diffuse large B-cell lymphoma (DLBCL) accompanied with KMT2D gene mutation and the impact of its co-mutated genes on prognosis. Methods Clinical data of 155 newly diagnosed DLBCL patients were obtained. The second-generation sequencing method was used to detect 475 hotspot genes, including KMT2D mutation. Patients were divided into the KMT2D mutation group and KMT2D wild-type group based on the presence or absence of KMT2D gene mutation. Clinical characteristics, differences in co-mutated genes, and survival differences between the two groups were compared. Results The frequency of KMT2D mutation was 31%, which is predominantly observed in elderly patients (P=0.07) and less in the double-expressor phenotype (P=0.07). Compared with the KMT2D wild-type group, KMT2D gene mutation was associated with higher co-mutation rates of CDKN2A (OR=2.82, P=0.01) and BCL2 (OR=3.84, P=0.016), while being mutually exclusive with MYC gene mutation (OR=0.11, P=0.013). In univariate survival analysis, no statistically significant difference in overall survival (OS) was found between the KMT2D mutation group and the wild-type group (P=0.54). Further analysis of the prognostic significance of KMT2D with other gene mutations indicated that patients with KMT2DmutBTG2mut had poorer OS than those with KMT2Dwt BTG2mut (P=0.07) and KMT2Dwt BTG2wt (P=0.05). On the contrary, patients with KMT2Dmut CD79Bmut had better OS than those with KMT2Dmut CD79Bwt (P=0.09), with no prognostic impact observed for other co-mutated genes. Multivariate Cox regression analysis revealed that Ann Arbor stages Ⅲ and Ⅳ (HR=2.751, 95%CI: 1.169-6.472, P=0.02), elevated LDH levels (HR=2.461, 95%CI: 1.396-4.337, P=0.002), Ki-67 index>80% (HR=1.875, 95%CI: 1.066-3.299, P=0.029), and KMT2DmutBTG2mut(HR=4.566, 95%CI: 1.348-15.471, P=0.015) were independent risk factors for OS in patients with DLBCL (P<0.05). Conclusion DLBCL patients with KMT2D mutation often have multiple gene mutations, among which patients with a co-mutated BTG2 gene have poor prognosis.
8.The value of bone marrow morphological minimal residual disease detection in the prognosis evaluation of elderly patients with multiple myeloma
Hong HUO ; Yantian ZHAO ; Jingchun ZHAI ; Zhiyao ZHANG ; Hong ZONG ; Guanfei ZHAO ; Guobin MA ; Sha LI ; Juan LYU
Chinese Journal of Geriatrics 2025;44(7):896-903
Objective:To investigate the relationship between the morphology of bone marrow plasma cells, the identification of M protein, and the detection of minimal residual disease(MRD)by flow cytometry in elderly patients with multiple myeloma(MM).Additionally, the impact on progression-free survival(PFS)is analyzed.Methods:A total of 60 elderly MM patients with bone marrow morphology reports and corresponding flow MRD detection, collected from February 1, 2017, to January 31, 2022, at Beijing Chaoyang Hospital Affiliated to Capital Medical University, were included in this study.We collected data on plasma cells from morphological examination and flow cytometry-based MRD detection. By combining these findings with M-protein identification results from 35 cases, we analyzed the correlations among these three parameters. Patients were stratified into two groups based on median values of: flow cytometry MRD(0.246% of nucleated cells), morphological plasma cell percentage(3.5%), and M-protein quantification(2.5 g/dl).This stratification enabled evaluation of their prognostic value for PFS.Results:A total of 60 elderly MM patients were enrolled, including 41 males with age of 65.0(63.0, 68.5)years and 19 females with age of 67.0(64.0, 72.0)years The morphology of bone marrow in 60 elderly patients with MM revealed 10 cases of primitive plasma cells(16.67%), 48 cases of immature plasma cells(80.00%), and 2 cases with no plasma cells(3.33%).A positive correlation was observed between the proportion of bone marrow plasma cells and the corresponding flow MRD in terms of both the proportion of nuclear cells and the proportion of plasma cells.Specifically, the proportion of the morphological protoplasma group showed a strong correlation with flow MRD(proportion of plasma cells)( r=0.82, P<0.01), while the proportion of the morphological immature plasma group exhibited moderate correlations with flow MRD(proportion of nuclear cells)( r=0.74, P<0.05)and flow MRD(proportion of plasma cells)( r=0.70, P<0.01).No significant correlation was found between the type and quantity of M protein and flow MRD( P>0.05).The PFS time for the flow MRD ≥0.246%(nucleated cells)group was shorter than that of the<0.246% group( P<0.05).There was no significant difference in PFS between the groups with plasma cell ratios ≥3.5% and<3.5%( P=0.15).Additionally, no significant difference in PFS was observed between patients with M protein quantitation ≥2.5 g/dl and those with M protein quantitation<2.5 g/dl( P=0.94). Conclusions:The proportion of bone marrow plasma cells correlates with flow MRD in elderly patients with MM, and a high MRD load indicates a poor prognosis.However, no significant correlation was found between M protein levels and flow MRD or PFS.Clinical attention should focus on the dynamic monitoring of plasma cell morphology and flow MRD.Nevertheless, the morphological detection of plasma cells remains crucial for auxiliary diagnosis due to its intuitiveness, cost-effectiveness, and broad applicability.
9.Maximum standard uptake value obtained with orbital SEPCT/CT for evaluating activity of thyroid-associated ophthalmopathy and predicting curative efficacy
Yihan ZHOU ; Sha LUO ; Shuang WANG ; Juan ZHANG ; Shiyu LUO ; Meng LI ; Junfang XIAN ; Mei LI
Chinese Journal of Medical Imaging Technology 2025;41(1):55-59
Objective To investigate the value of the maximum standard uptake value(SUVmax)obtained with orbital SEPCT/CT for evaluating activity of thyroid-associated ophthalmopathy(TAO)and predicting curative efficacy.Methods A total of 96 patients with initially diagnosed TAO were retrospectively collected,including 71 with clinical activity score(CAS)≥3(active group)and 25 with CAS=2(inactive group).Data of orbital SEPCT/CT were collected,and the patients were treated with hormones or immunosuppressants for 3 months.CAS was performed again within 1 week after treatment,and orbital imaging was reviewed.The patients were divided into effective group and ineffective group according to treatment results.Pretreatment(pre)SUVmax(pre-SUVmax)and imaging agent uptake rate(UR)(pre-UR)in extraocular muscle were compared between active and inactive groups.Pre-CAS,post-treatment(post)CAS(post-CAS),as well as pre-SUVmax,post-SUVmax,pre-UR,post-UR and the difference of pre-and post-treatment CAS,SUVmax and UR(△CAS,△UR,△SUVmax)of extraocular muscle were compared between effective group and ineffective group.The correlations of SUVmax,UR and CAS were analyzed.Pre-CAS,pre-SUVmax and pre-UR were included in univariate and multivariate logistic regression analysis to screen the predictors of effective treatment of TAO.Results Pre-SUVmax and pre-UR of extraocular muscle in active group were higher than those in inactive group(both P<0.05).Among 96 cases,70 were in effective group and 26 were in ineffective group.Pre-CAS,the proportion of pre-CAS≥3 scores,pre-SUVmax,pre-UR,△CAS,△SUVmax and △UR in effective group were all higher than those in ineffective group(all P<0.05).Pre-SUVmax and pre-UR in extraocular muscle of TAO patients were positively correlated with pre-CAS(rs=0.419,0.395,both P<0.001),while post-SUVmax and post-UR were positively correlated with post-CAS(rs=0.322,0.221,P=0.001,0.030),△SUVmax and △UR were positively correlated with △CAS(rs=0.368,0.206,P<0.001,P=0.044).Pre-CAS≥3(OR=2.95)and pre-SUVmax(OR=4.22)were both independent predictors of effective treatment of TAO(both P<0.05).Conclusion SUVmax obtained with orbital SEPCT/CT could be used to quantitatively assess TAO activity and predict curative efficacy.
10.Experiences of food avoidance behavior in patients with inflammatory bowel disease:a qualitative study
Qingyu WANG ; Meijing ZHOU ; Yang LEI ; Sha LI ; Junyi GU ; Zheng LIN ; Qiugui BIAN ; Jiefeng YANG ; Lichen TANG ; Jiali CHEN ; Hantian CHENG
Chinese Journal of Nursing 2025;60(11):1323-1329
Objective This study applies Roy adaptation theory to deeply explore the experience of food avoid-ance behavior in patients with inflammatory bowel disease(IBD),offering insights for developing dietary management strategies.Methods A descriptive qualitative research method was employed.By purposive sampling,24 IBD pa-tients hospitalized in the gastroenterology department of a tertiary hospital in Nanjing from July 2022 to December 2024 were selected for semi-structured interviews.Data were analyzed using a directed content analysis approach.Results This study identified 4 main themes and 11 sub-themes,encompassing overattribution leading to inappro-priate avoidance(recurrent symptoms triggering overattribution,disease staging triggering inappropriate avoidance),negative self-perception leading management struggles(illness fear diminishing self-efficacy,disease trauma eroding self-identity,knowledge deficiency constraining self-determination),functional impairment intensifying role challenges(role internalization undermining social function,social roles relinquishing dietary management),and external con-straints amplifying practical difficulties(family and friend oversight heightening dietary stress,healthcare gaps foster-ing practical helplessness,traditional beliefs restricting dietary exploration,economic hardship limiting balanced nu-trition).Conclusion The interplay of overattribution,negative self-perception,functional impairment,and external constraints in IBD patients hinders their ability to adapt to disease fluctuations,ensnaring them in the adaptive predicament of food avoidance behavior.Healthcare professionals should comprehensively address these factors by fostering accurate perceptions,enhancing psychological support,guiding effective coping strategies,and optimizing ex-ternal resources,thereby improving patients' overall adaptive capacity and promoting their recovery.


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