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ObjectiveThe mechanisms driving the progression of infantile spasms are not well understood. We aimed to investigate the changes and correlations of the gut microbiota, the hypothalamus–pituitary–adrenal (HPA) axis hormones, and the inflammatory cytokines in children with infantile spasms before and after treatment in order to provide a reference for future pathogenesis research.MethodsChildren with infantile spasms who were admitted to our hospital were recruited into the case group. The case group was divided into the pre-treatment group (group A, n = 14), the 2 weeks after treatment group (group B), and the 1 month after treatment group (group C). On the other hand, healthy children with the same sex ratio as the case group were recruited into the control group (group D, n = 14). Three stool and blood samples were collected before treatment, 2 weeks after treatment, and 1 month after treatment. The serum samples were analyzed using cytometric bead array (CBA), enzyme-linked immunosorbent assay (ELISA), and chemiluminescent immunoassay (CLIA) to measure the levels of HPA axis hormones and inflammatory cytokines. The collected stool samples were sequenced using 16S rDNA.ResultsThe pre-treatment group demonstrated elevated levels of corticotropin-releasing hormone (CRH), interleukin 2 (IL-2), IL-4, IL-6, and IL-17α, which decreased with treatment. The level of CRH was lower in the effective group than that in the ineffective group. Sutterellaceae was lower in the pre-treatment group than that in the control group. Lachnospiracea_incertae_sedis was positively associated with CRH concentration (p < 0.05). After treatment, Sutterellaceae was negatively associated with IL-2 and TNF-α (p < 0.05).ConclusionThis study found that imbalance of the gut microbiota may be involved in the pathogenesis of infantile spasms and is related to the response to adrenocorticotropic hormone (ACTH). Lachnospiraceae and Lachnospiracea_incertae_sedis might be involved in the disease onset. Sutterellaceae might have a link to children’s improved health.

The anti-tumoral effects of metformin have been widely studied in several types of cancer, including thyroid cancer; however, the underlying molecular mechanisms remain poorly understood. As an oral hypoglycemic drug, metformin facilitates glucose catabolism and disrupts metabolic homeostasis. Metabolic reprogramming, particularly cellular glucose metabolism, is an important characteristic of malignant tumors. This study aimed to explore the therapeutic effects of metformin in thyroid cancer and the underlying metabolic mechanism. In the present study, it was shown that metformin reduced cell viability, invasion, migration, and EMT, and induced apoptosis and cell cycle G1 phase arrest in thyroid cancer. Transcriptome analysis demonstrated that the differentially expressed genes induced by metformin were involved in several signaling pathways including apoptosis singling pathways, TGF-β signaling, and cell cycle regulation in human thyroid cancer cell lines. In addition, the helicase activity of the CDC45-MCM2–7-GINS complex and DNA replication related genes such as RPA2, RAD51, and PCNA were downregulated in metformin-treated thyroid cancer cells. Moreover, metabolomics analysis showed that metformin-induced significant alterations in metabolic pathways such as glutathione metabolism and polyamine synthesis. Integrative analysis of transcriptomes and metabolomics revealed that metformin suppressed glycolysis by downregulating the key glycolytic enzymes LDHA and PKM2 and upregulating IDH1 expression in thyroid cancer. Furthermore, the anti-tumor role of metformin in thyroid cancer in vivo was shown. Together these results show that metformin plays an anti-tumor role by inhibiting glycolysis and restraining DNA replication in thyroid cancer.

Congenital anomalies of the kidney and urinary tract (CAKUT) is a general term for a class of diseases that are mostly caused by intrauterine genetic development limitation. Without timely intervention, certain children with CAKUT may experience progressive decompensation and a rapid decline in renal function, which will ultimately result in end-stage renal disease. At present, a comprehensive understanding of the pathogenic signaling events of CAKUT is lacking. The role of long noncoding RNAs (lncRNAs) in renal development and disease have recently received much interest. In previous research, we discovered that mice overexpressing the lncRNA 4933425B07Rik (Rik) showed a range of CAKUT phenotypes, primarily renal hypoplasia. The current study investigated the molecular basis of renal hypoplasia caused by Rik overexpression. We first used Rapid Amplification of cDNA ends (RACE) to obtain the full-length sequence of Rik in Rik+/+;Hoxb7 mice. Mouse proximal renal tubule epithelial cells (MPTCs) line with Rik overexpression was constructed using lentiviral methods, and mouse metanephric mesenchyme cell line (MK3) with Rik knockout was then constructed by the CRISPR‒Cas9 method. We performed RNA-seq on the Rik-overexpressing cell line to explore possible differentially expressed molecules and pathways. mRNA expression was confirmed by qRT‒PCR. Reduced levels of Wnt10b, Fzd8, and β-catenin were observed when Rik was expressed robustly. On the other hand, these genes were more highly expressed when Rik was knocked out. These results imply that overabundance of Rik might inhibit the Wnt/β-catenin signaling pathway, which may result in renal hypoplasia. In general, such research might help shed light on CAKUT causes and processes and offer guidance for creating new prophylactic and therapeutic strategies.

Abstract Background Bacterial meningitis (BM) is a life-threatening infectious disease of the central nervous system in infants and children. To date, no diagnostic methods for the early and precise diagnosis of paediatric BM have been developed. Methods A label-free cerebrospinal fluid (CSF) quantitative proteomic analysis of 8 patients with confirmed or suspected BM, 9 patients with confirmed or suspected viral meningitis (VM) and 6 non-CNS-infected hospital patients was performed via high-resolution LC–MS/MS. Results Our CSF proteomic analysis allowed the identification of critical differences between the BM and non-BM groups. Compared to the proteomes of the non-BM groups, the proteome of the paediatric BM group was characterized by upregulation of complement and coagulation cascades, regulation of IGF transport, uptake by IGF-binding proteins and acute inflammatory response, downregulation of developmental growth, and metabolism of carbohydrates. Moreover, the levels of CD163, A2M and full-length APP in CSF showed excellent diagnostic performance for paediatric BM, with AUC values of 0.911 (95% CI: 0.839–0.984), 0.908 (95% CI: 0.816–1.000) and 0.944 (95% CI: 0.86, 1.000), respectively. Among them, A2M and full-length APP are reported here for the first time as potential diagnostic biomarkers of BM. The findings imply that peptidase regulator activity plays an important role in BM and provide potential novel targets for precision medicine in paediatric BM. Conclusions CD163, A2M and full-length APP are validated as potential diagnostic biomarkers of paediatric BM.

An effective and comprehensive quality evaluation method for Liuwei Dihuang pills (LDP) was established by the simultaneous determination of 8 active components in LDP by the quantitative analysis of multicomponents by single marker (QAMS) method and high-performance liquid chromatography (HPLC) fingerprint combined with chemometrics. These 8 active components were determined by QAMS and the external standard method (ESM), and the quantitative results of the two methods were compared to validate the accuracy and feasibility of the QAMS method. 8 active components showed good linear relationships within their ranges, whose average recoveries were 99.7∼102.3%. No significant difference was found (P>0.05) in the quantitative results determined by QAMS and ESM. Furthermore, the fingerprint of LDP was also established, with 11 common peaks identified, and the similarity of the fingerprints of 21 batches of LDP was greater than 0.95. The 21 batches of LDP were basically divided into 3 groups by hierarchical cluster analysis (HCA) and principal component analysis (PCA), and 3 differential markers were screened out by orthogonal partial least squares discriminant analysis (OPLS-DA). The established QAMS method is accurate, economical, fast, and convenient and can simultaneously determine the content of 8 active components in LDP. HPLC fingerprint combined with chemometric analysis more comprehensively evaluated the quality consistency of different batches of LDP and analyzed the markers that cause quality differences between batches. It can provide a scientific basis and reference of quality consistency evaluation for the manufacturers and drug regulatory departments of the preparation.

Background: Gen1 mutation can cause various phenotypes of congenital anomaly of the kidney and urinary tract (CAKUT). An intrauterine low-protein isocaloric diet can also cause CAKUT phenotypes in offspring. However, single factors such as gene mutation or abnormal environmental factor during pregnancy can only explain part of the pathogenesis of CAKUT. Objectives: A low-protein isocaloric diet was fed to Gen1-mutant mice throughout pregnancy to establish a Gen1-mutant mouse model exposed to a low-protein isocaloric intrauterine environment. The mice were divided into 4 groups: normal (22%) protein diet (ND) + wild-type mice (CON group), ND + Gen1PB/+ mice (Gen1PB/+ group), low (6%)-protein isocaloric diet (LD) + wild-type mice (LD group), and the LD + Gen1PB/+ groups. Methods: The experimental design included observing proportion and distribution of CAKUT phenotypes of neonatal mice; evaluating the number of ureteric buds (UBs) on embryonic day (E) 11.5, the location of UBs on E11.5, and length of the common nephric duct (CND); isolating embryonic kidneys on E11.5 from the Gen1PB/+ group and culturing embryonic kidneys in medium containing 10% serum or serum-free medium to observe the branching of UBs; and detecting the p-PLCγ, p-Akt, and p-ERK1/2 in UBs and CND on E11.5, as well as the apoptosis and proliferation of tissues by immunofluorescence staining. Results: We found that the incidence of CAKUT in offspring of Gen1PB/+ mice under an intrauterine low-protein isocaloric diet environment was significantly increased, and a duplicated collecting system was the dominant phenotype of CAKUT. During the early stage of metanephric development, ectopic protrusion of UBs may appear and lower locations of UBs in Gen1PB/+ mice under an intrauterine low-protein isocaloric diet environment and the number of UB branches in the serum-free culture condition significantly decreased. Further examination revealed that p-PLCγ signaling and tissue apoptosis were abnormal in UBs and the CND at the early stage of kidney development. Conclusions: The aforementioned findings suggest that an intrauterine low-protein isocaloric diet can aggravate the occurrence of CAKUT in Gen1-mutant mice, which might affect key steps in the metanephric development, such as the protrusion of UBs, which might be related to mediate UBs and CND apoptosis through p-PLCγ signaling.

Congenital anomalies of the kidney and urinary tract (CAKUT) are some of the most common developmental defects and have a complicated etiology, indicating an interaction of (epi-) genetic and environmental factors. Single gene mutations and copy number variations (CNVs) do not explain most cases of CAKUT, and simultaneous contributions of more than one gene (di-, oligo-, or polygenic effects; i.e., complex genetics) may lead to the pathogenesis of CAKUT. Robo2 plays a key role in regulating ureteric bud (UB) formation in the embryo, with mutations leading to supernumerary kidneys. Gen1 is a candidate gene associated with CAKUT because of its important role in early metanephric development in mice. We established a mouse model with double disruption of Robo2 and Gen1 using a piggyBac transposon and found that double gene mutation led to significantly increased CAKUT phenotypes in Robo2PB/+Gen1PB/+ mouse offspring, especially a duplicated collecting system. Increased ectopic UB formation was observed in the Robo2PB/+Gen1PB/+ mice during the embryonic period. Robo2 and Gen1 exert synergistic effects on mouse kidney development, promoting cell proliferation by activating the GDNF/RET pathway and downstream MAPK/ERK signaling. Our findings provide a disease model for CAKUT as an oligogenic disorder.

Abstract Hand, foot, and mouth disease (HFMD) is endemic in the Pacific region, especially in mainland China. The case-fatality ratio of HFMD is increasing steadily. Knowledge of the changing epidemiology of HFMD in different regions is necessary for implementing appropriate intervention strategies. In this study, we describe the clinical and epidemiological characteristics of HFMD in Hunan Children’s Hospital between 2013 and 2017. A total of 7203 patients with HFMD were admitted, with complication and mortality rates of 35.62% and 0.78%, respectively. The total number of children with HFMD, proportion of severely ill children, and HFMD mortality rate were the highest in 2014. The number of cases caused by EV-A71 and CV-A16 decreased continuously, while the number of cases caused by ‘other enteroviruses’ increased yearly since 2014, suggesting that other enteric viruses will gradually replace EV-A71 and CV-A16 as the main pathogenic HFMD agents. Furthermore, EV-A71 and mixed infections accounted for the high case fatality rates in children with severe HFMD, among whom EV-A71 infection resulted in the highest complication and mortality rates; the mild form of the disease was dominated by ‘other enteroviruses’. In conclusion, the changing etiological pattern highlights the need to improve pathogen surveillance and vaccine strategies for HFMD control.

Objective: Anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis is the most common autoimmune encephalitis in pediatric patients. The study aimed to investigate the clinical characteristics and prognostic factors of anti-NMDA receptor encephalitis in children in South China.Methods: This was a retrospective study of children diagnosed with anti-NMDA receptor encephalitis between 01/2014 and 12/2017 at Hunan Children's Hospital. Laboratory, brain magnetic resonance imaging (MRI), and electroencephalography data were collected. The short-term (6-month) outcomes were assessed using the Liverpool score by the same pediatric neurologist. The children were divided into good (scores 4–5) and poor (score

Congenital anomalies of the kidney and urinary tract (CAKUT) is a common birth defect and is the leading cause of end-stage renal disease in children. The etiology of CAKUT is complex and includes mainly genetic and environmental factors. However, these factors cannot fully explain the etiological mechanism of CAKUT. Recently, participation of long non-coding RNAs (lncRNAs) in the development of the circulatory and nervous systems was demonstrated; however, the role of lncRNAs in the development of the kidney and urinary tract system is unclear. In this study, we used the piggyBac (PB) transposon-based mutagenesis to construct a mouse with lncRNA 4933425B07Rik (Rik) PB insertion (RikPB/PB) and detected overexpression of Rik and a variety of developmental abnormalities in the urinary system after PB insertion, mainly including renal hypo/dysplasia. The number of ureteric bud (UB) branches in the RikPB/PB embryonic kidney was significantly decreased in embryonic kidney culture. Only bone morphogenetic protein 4 (Bmp4), a key molecule regulating UB branching, is significantly downregulated in RikPB/PB embryonic kidney, while the expression levels of other molecules involved in the regulation of UB branching were not significantly different according to the RNA-sequencing (RNA-seq) data, and the results were verified by quantitative real-time polymerase chain reaction (RT-PCR) and immunofluorescence assays. Besides, the expression of pSmad1/5/8, a downstream molecule of BMP4 signaling, decreased by immunofluorescence. These findings suggest that abnormal expression of Rik may cause a reduction in the UB branches by reducing the expression levels of the UB branching-related molecule Bmp4, thus leading to the development of CAKUT.

Unconventional oil and gas reservoirs have broad exploration and development prospects. Fracture parameters and effectiveness evaluation are two of the key tasks for the evaluation of these types of reservoirs. Array acoustic logging can be used for fracture evaluation to compensate for the deficiencies of the image logging fracture evaluation method. Therefore, to develop acoustic logging evaluation methods as well as nondestructive testing methods for fractures, experiments were conducted to study the shear wave transmission in fractured media. Experiment data demonstrate a good correlation between the shear wave attenuation coefficient and fracture width, and the shear wave attenuation coefficients rise logarithmically with the increase in the fracture width for all models with different porosities and distinct dip angles of fractures. The shear wave attenuation coefficient changes relatively faster with the fracture width when the fracture width is within 250 μm. In addition, the shear wave attenuation is affected by the core porosity and fracture dip angle. When the fracture width is constant, the shear wave attenuation caused by the 0° fracture is relatively larger and is obviously greater than that of the fractures at other angles, which is consistent with the existing experimental results. The results of this study can be used to guide further research on amplitude compensation methods for sonic signal transmission in fractured media and fracture evaluation methods.

Single-nucleotide variants (SNVs) are the most common genetic variants and universally present in the human genome. Genome-wide association studies (GWASs) have identified a great number of disease or trait-associated variants, many of which are located in non-coding regions. Long intergenic non-protein coding RNAs (lincRNAs) are the major subtype of long non-coding RNAs; lincRNAs play crucial roles in various disorders and cellular models via multiple mechanisms. With rapid growth in the number of the identified lincRNAs and genetic variants, there is great demand for an investigation of SNVs in lincRNAs. Hence, in this article, we mainly summarize the significant role of SNVs within human lincRNA regions. Some pivotal variants may serve as risk factors for the development of various disorders, especially cancer. They may also act as important regulatory signatures involved in the modulation of lincRNAs in a tissue- or disorder-specific manner. An increasing number of researches indicate that lincRNA variants would potentially provide additional options for genetic testing and disease risk assessment in the personalized medicine era.

Severe mental illness (SMI) represents major social and public health problem in China, especially in low- or middle-income regions. We aim to assess the prevalence and distribution of SMI in Hunan province in central China.Multistage stratified random sampling methods were used to select qualified subjects in 123 districts and counties in Hunan province. 89465 individuals were randomly identified, and 72999 (81.6%) completed the supplemental 12-Item General Health Questionnaire (GHQ-12) and Cue questionnaire of psychiatric abnormal behaviors. 6082 suspected individuals having high or moderate risk, or psychiatric cues, were administered the Structured Clinical Interview for DSM-IV Axis I disorders (SCID-I) by psychiatrists.720 respondents were definitely diagnosed as SMI. The 1-month and lifetime prevalence was 9.35‰ and 10.10‰, respectively. The most frequent SMI was schizophrenia, followed by bipolar disorder, intellectual disability, epileptic mental disorder, paranoid psychosis and schizoaffective disorders, with 1-month prevalence ranging from 0.11‰ to 6.50‰ and lifetime prevalence ranging from 0.24‰ to 6.86‰. Multivariate logistic regression analysis revealed that lower education, farmer occupation, retirees or jobless/unemployed, unmarried or divorced and age of 30-64 years old were major factors that associated with the increased risk of SMI. In addition, only 33.3% of 528 patients who completed questionnaire sought help in psychiatric institutions, and up to 51.7% of 720 patients were not referred to the SMI management system in Hunan province.These findings provided a large-scale prevalence data of SMI in a provincial sample of China. The psychiatric disorders brought economical and psychological burden for family and society, which may shed light on the significance of scaling up province-wide mental health service and strengthening the SMI management.

The offspring of Robo2 mutant mice usually present with variable phenotypes of congenital anomalies of the kidney and urinary tract (CAKUT). An intrauterine low-protein diet can also cause CAKUT in offspring, dominated by the duplicated collecting system phenotype. A single genetic or environment factor can only partially explain the pathogenesis of CAKUT. The present study aimed to establish an intrauterine low-protein diet roundabout 2 (Robo2) mutant mouse model and found that the intrauterine low-protein diet led to significantly increased CAKUT phenotypes in Robo2PB/+ mice offspring, dominant by a duplicated collecting system. At the same time, more ectopic and lower located ureteric buds (UBs) were observed in the intrauterine low-protein diet-fed Robo2 mutant mouse model, and the number of UB branches was reduced in the serum-free culture. During UB protrusion, intrauterine low-protein diet reduced the expression of Slit2/Robo2 in Robo2 mutant mice and affected the expression of glial cell-derived neurotrophic factor/Ret, which is a key molecule for metanephric development, with increasing phospho-Akt and phospho-cAMP responsive element-binding protein 3 activity and a reduction of apoptotic cells in embryonic day 11.5 UB tissues. The mechanism by which an intrauterine low-protein diet aggravates CAKUT in Robo2 mutant mice may be related to the disruption of Akt/cAMP responsive element-binding protein 3 signaling and a reduction in apoptosis in UB tissue. [ABSTRACT FROM AUTHOR]

BackgroundThe management of latent tuberculosis infection (LTBI) is a key action for the realization of the “End tuberculosis (TB) Strategy” worldwide, and it is important to identify priority populations. In this prospective cohort study, we evaluated the prevalence of LTBI and incidence of active TB among close contacts and explored the suitable TB control strategy in schools.MethodsWe designed a cohort with 2 years of follow-up, recruiting freshman/sophomore TB patients’ close contacts from three administrative districts in Shanghai. These were chosen based on different levels of TB incidence reported in 2019. Questionnaires were included and all participants received both tuberculin skin test (TST) and QuantiFERON-TB Gold (QFT) at baseline, then tracked the outcomes of them during the follow-up period.ResultsThe prevalence of LTBI was 4.8% by QFT. Univariate analysis showed that the risk of LTBI was higher in those contacting bacteriologically confirmed patients or did not have BCG scars, including smokers. The risk increased with poor lighting and ventilation conditions at contact sites. Multivariate analysis showed that those contacting with bacteriologically confirmed patients (OR=4.180; 95%CI, 1.164-15.011) or who did not have BCG scars (OR=5.054; 95%CI, 2.278-11.214) had a higher risk of being LTBI, as did the current smokers (OR=3.916; 95%CI, 1.508-10.168) and those who had stopped smoking (OR=7.491; 95%CI, 2.222-25.249). During the 2-year follow-up period, three clinically diagnosed cases of TB were recorded, the 2-year cumulative incidence was 0.4% (95%CI 0.1-1.2), the median duration for TB occurrence was 1 year, the incidence rate of active TB was 2.0 per 1000 person-years with a total of 1497.3 observation person-years. For those LTBI, no one initiated preventive treatment, in the QFT (+) cohort, 1 TB case was observed, 71 person-years with an incidence rate of 14.1 14.1 (95%CI 2.5-75.6) per 1000 person-years, in the TST (+++) cohort, 2 TB cases were observed 91.5 person-years with an incidence rate of 21.9 (95%CI 6.0-76.3) per 1000 person-years.ConclusionsThe results suggest that school close contacts are one of the key populations for LTBI management. Measures should be taken to further reduce the prevalence of LTBI and the incidence of active TB among them.

Background Meiotic homologous recombination (HR) plays an essential role in gametogenesis. In most eukaryotes, meiotic HR is mediated by two recombinase systems: ubiquitous RAD51 and meiosis-specific DMC1. In the RAD51-mediated HR system, RAD51 and five RAD51 paralogues are essential for normal RAD51 function, but the role of RAD51 in human meiosis is unclear. The knockout of Rad51 or any Rad51 paralogue in mice exhibits embryonic lethality. We investigated a family with meiotic arrest, azoospermia and infertility but without other abnormalities. Methods Homozygosity mapping and whole-exome sequencing were performed in a consanguineous family. An animal model carrying a related mutation was created by using a CRISPR/Cas9 system. Results We identified a 1 bp homozygous substitution (c.41T>C/p.Leu14Pro) on a RAD51 paralogue, namely, XRCC2, in the consanguineous family. We did not detect any XRCC2 recessive mutation in a cohort of 127 males with non-obstructive-azoospermia. Knockin mice with Xrcc2-c.T41C/p.Leu14Pro mutation were generated successfully by the CRISPR/Cas9 method. The homozygotes survived and exhibited meiotic arrest, azoospermia, premature ovarian failure and infertility. Conclusion A XRCC2 recessive mutation causing meiotic arrest and infertility in humans was duplicated with knockin mice. Our results revealed a new Mendelian hereditary entity and provided an experimental model of RAD51-HR gene defect in mammalian meiosis. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. To identify AD-related genes from transcriptomics and help to develop new drugs to treat AD. In this study, firstly, we obtained differentially expressed genes (DEG)-enriched coexpression networks between AD and normal samples in multiple transcriptomics datasets by weighted gene co-expression network analysis (WGCNA). Then, a convergent genomic approach (CFG) integrating multiple AD-related evidence was used to prioritize potential genes from DEG-enriched modules. Subsequently, we identified candidate genes in the potential genes list. Lastly, we combined deepDTnet and SAveRUNNER to predict interaction among candidate genes, drug and AD. Experiments on five datasets show that the CFG score of GJA1 is the highest among all potential driver genes of AD. Moreover, we found GJA1 interacts with AD from target-drugs-diseases network prediction. Therefore, candidate gene GJA1 is the most likely to be target of AD. In summary, identification of AD-related genes contributes to the understanding of AD pathophysiology and the development of new drugs.

Background: Tuberculosis (TB) is a critical global public threat, and limited epidemiology studies have been performed to explore the efficacy of active TB screening. Methods: Three sites located in eastern China were chosen in 2013, and three rounds of systematic screenings were performed in permanent residents aged older than 15 years. Results: The TB incidence showed a downtrend after several rounds of active screening at the three sites, and a significant change was observed at site A in the overall population. In the target population at sites A and B, both the elderly and people with a history of TB had a remarkable decline through the first or second round of screening. The implementation of active case-finding identified 2.36 [1.47,3.81] (2013 vs. 2012) and 1.49 [1.1,2.03] (2013–2015 vs. 2010–2012) more potential cases than the passive case-finding by the surveillance system at site A. Conclusions: Active case-finding of tuberculosis might be effective in high prevalence area with a low economic level, particularly among the elderly and people with a history of TB. Additionally, new rapid diagnosis technology should be considered to decrease the prevalence among people with a history of TB. Ultimately, active screening identified more active TB cases than passive case-finding, particularly in high prevalence area with underdeveloped economics. Keywords: Tuberculosis, Active screening, High prevalence, Target population

On social platforms like Facebook, it is popular and pleasurable to share photos among friends, but it also puts other participants in the same picture in jeopardy when the photos are released online without the permission from them. To solve this problem, recently, the researchers have designed some fine-grained access control mechanisms for photos shared on the social platform. The uploader will tag each participant in the photo, then they will receive internal messages and configure their own privacy control strategies. These methods protect their privacy in photos by blurring out the faces of participants. However, there is still some defect in these strategies due to the unpredictable tagging behaviors of the uploader. Malicious users can easily manipulate unauthorized tagging processes and then publish the photos, which the participants want them to be confidential in social media. To address this critical problem, we propose a participant-free tagging system for photos on social platforms. This system excludes potential adversaries through automatic tagging processes over two cascading stages: 1) an initialization stage will be applied to every new user to collect his/her own portrait samples for future internal searching and tagging, and; 2) the remaining unidentified participants will be tagged in cooperative tagging stage by the users who have been identified in the first stage. For the system evaluation of efficiency and effectiveness, we conducted a series of experiments. The results demonstrated the tagging efficiency (96% tagging rate and 0.77s/photo tagging speed on average), photo masking and unmasking efficiency (0.13s/face on average), and the privacy preserving performance (over 90% identities in both group and individual photo are preserved).