Single-cell analysis reveals a unique microenvironment in peri-implantitis

AIM

This study aimed to reveal the unique microenvironment of peri-implantitis through single-cell analysis.

MATERIALS AND METHODS

Herein, we performed single-cell RNA sequencing (scRNA-seq) of biopsies from patients with peri-implantitis (PI) and compared the results with healthy individuals (H) and patients with periodontitis (PD).

RESULTS

Decreased numbers of stromal cells and increased immune cells were found in the PI group, which implies a severe inflammatory infiltration. The fibroblasts were found to be heterogeneous and the specific pro-inflammatory CXCL13+ sub-cluster was more represented in the PI group, in contrast to the PD and H groups. Furthermore, more neutrophil infiltration was detected in the PI group than in the PD group, and cell-cell communication and ligand-receptor pairs revealed most neutrophils were recruited by CXCL13+ fibroblasts through CXCL8/CXCL6-CXCR2/CXCR1. Notably, our study demonstrated that the unique microenvironment of the PI group promoted the differentiation of monocyte/macrophage lineage cells into osteoclasts, which might explain the faster and more severe bone resorption in the progression of PI than PD.

CONCLUSIONS

Collectively, this study suggests a unique immune microenvironment of PI, which may explain the differences between PI and PD in the clinic. These outcomes will aid in finding new specific and effective treatments for PI.

[Value of metagenomic next-generation sequencing in the etiology diagnosis of bacterial meningitis in children]

Objective: To explore the value of metagenomic next-generation sequencing (mNGS) in the etiology diagnosis of bacterial meningitis in children. Methods: The etiological results of 189 children diagnosed with "bacterial meningitis" or "purulent meningitis" or "central nervous system infection" in the Children's Hospital of Fudan University from 1st January 2019 to 31st December 2020 were analyzed retrospectively. The cerebrospinal fluid (CFS) of the children with bacterial meningitis was detected by culture and mNGS respectively, and the difference of pathogen detection rate between the 2 methods was analyzed. According to the age at the time of visit, the children were divided into neonatal group (≤28 days of age) and non-neonatal group (>28 days of age), and χ² test was used to compare the positive rate between the 2 groups. Taking CFS culture as the gold standard, the sensitivity and specificity of mNGS in the diagnosing of bacterial meningitis in children were analyzed. Results: Among these 189 children with bacterial meningitis, 116 were males and 73 were females. A total of 76 strains of pathogens were detected in blood and (or) CSF cultures, of which 50 strains (65.8%) were Gram-positive bacteria; among those, 18 strains (23.7%) of Streptococcus agalactiae, 17 strains (19.7%) of Escherichia coli and 15 strains (19.7%) of Streptococcus pneumoniae were detected with higher detection rate. The infection rate of Gram-positive bacteria in the non-neonatal group was higher than that in the neonatal group (76.0% (38/50) vs. 50.0% (13/26), χ²=5.24, P=0.020).The same CSF samples of 48 cases were tested by mNGS and culture at the same time, and the detection rate of mNGS was higher than that of CSF culture (20 cases (41.7%) vs. 12 cases (25.0%), χ²=16.45, P<0.001). The consistency of mNGS and culture results was 79.2% (38/48), and the same pathogen was detected in 11 children with both positive mNGS and CSF culture. Taking the results of CSF culture as the gold standard, the sensitivity of mNGS in the diagnosing of bacterial meningitis was 91.7%, and the specificity was 75.0%. Conclusions: The mNGS technology can improve the pathogen detection rate of bacterial meningitis in children, and has a high consistency with CSF culture. In suspected cases where the pathogen cannot be identified by traditional methods, CSF mNGS should be considered timely.

[To take the initiative in the prevention and control of the coronavirus disease 2019 epidemic in the changing and unchanged strategies]

In early 2020, an outbreak of coronavirus disease 2019 (COVID-19) epidemic happened in China. In the following three months, 42 600 medical personnels and more than 9 000 public health employees were "rushed out" of their own position and onto Wuhan and other areas in Hubei Province. They helped to strengthen the treatment of severe cases and the isolation of mild cases, and actively carried out community screenings, and eventually won victory in the defense of Wuhan. During the normalization stage of prevention and control of the epidemic of COVID-19, China adopted the expanded preventive strategy by focusing on widely implement PCR testing, and integrate general and emergency departments to improve the performance of public health system. In this stage, China put out the cluster of epidemics that have occurred in several places one after another, and effectively controlled the spread of the epidemic in 2 to 3 incubation periods. In the stage of "dynamic zeroing", China emphasized the strategy of "grasping early, grasping the basics", focused on specific measures such as precise prevention in key areas. The rule of golden 24 hours was used to control the spread of the epidemic within one incubation period. During the epidemic, China continues to adopt active prevention and control strategies. This self-confidence and determination depends on adhering to the leadership of the Communist Party of China, the distinct essence of medical and health services, and significant advantages of social governance on health.

[Etiology and clinical characteristics of fever of unknown origin in 357 pediatric patients]

Objective: To explore the etiologies and clinical characteristics of fever of unknown origin (FUO) and to provide clues for early diagnosis of FUO. Methods: The data about etiology, age, sex, clinical course, length of hospital stays and the expression levels of inflammatory factors in fever phase of 357 pediatric inpatients who were diagnosed with FUO in Children's Hospital of Fudan University from 1 January 2016 to 31 December 2020 were collected and retrospectively analyzed. Participants were grouped into infectious disease, inflammatory disease, malignancy and others and according to the classification of diseases and also grouped into those aged<1 year, 1-<3 years,3-<6 years, 6-<12 years and 12-<18 years. Comparisons between groups were performed using the Mann-Whitney U test, Kruskal-Wallis H test and χ² test. Results: Among the 357 patients (217 males and 140 females). The age of onset was 3.9 (1.3, 9.2) years and visiting age was 5.1 (2.0, 9.3) years. The time-consuming of diagnosis was 94 (66, 213) days. The hospital stay was 8 (6, 14) days. The most frequently identified cause of FUO was infectious diseases (163 cases, 45.7%), followed by non-infectious inflammatory diseases (133 cases, 37.2%), malignancy (21 cases, 5.9%) and others (40 cases, 11.2%). The patients at younger age were more likely to be attacked by malignancy, oncologic diagnoses, and others, nevertheless patients at older age were more likely to be attacked by non-infectious inflammatory diseases oppositely (9.8 (3.6, 11.5) vs. 3.0 (1.2, 7.0), 2.3 (1.0, 5.2), 0.9 (0.5, 1.8) years, U=41.30, 15.94, 37.08, all P<0.01);106 (65%) patients were male, and 57 (35%) patients were female. This result indicated that boys were more susceptible to infectious diseases (χ²=14.73, P<0.01). Analysis of inflammatory factors in serum among 103 patients, interleukin (IL)-6 level in 40 infectious diseases patients (9 (2, 38) ng/L) was significantly lower than those of 6 tumor patients (89 (64, 599) ng/L) and 57 non-infectious inflammatory diseases patients (25 (8, 78) ng/L, U=51.05, 15.70, both P<0.05), no significant difference was observed in IL-2, IL-4, IL-10, tumor necrosis factor α and interferon among the groups (all P>0.05). The patients grouped into those aged 1-<3 years and 3-<6 years were more likely to be attacked by infectious diseases (51.3% (59/115) and 57.1% (40/70)), while patients grouped into those aged 6-<12 years and 12-<18 years were more likely to be attacked by non-infectious inflammatory diseases (55.6% (65/117) and 72.4% (21/29)). Conclusions: Infectious disease is still the main cause of FUO in children and the boys are more susceptible to infectious diseases. However, the morbidity of non-infectious inflammatory diseases increases to number 1 in FUO of children over 6 years of age.

[Value of albumin in diagnosis of neonatal intrahepatic cholestasis caused by citrin deficiency]

Objective: To investigate the clinical value of albumin (Alb) in the diagnosis of neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD). Methods: A retrospective analysis was performed for the clinical data of 90 children with NICCD who visited Children's Hospital of Fudan University from January 2007 to December 2014, and according to the content of Alb, these children were divided into Alb < 30 g/L (LA) group with 20 children and Alb ≥30 g/L (NA) group with 70 children. The clinical manifestations, results of laboratory examination, results of blood tandem mass spectrometry and urine gas chromatography-mass spectrometry, and gene detection results were compared between the two groups. The t-test and the chi-square test were used for statistical analysis.. Results: There were significant differences between the LA group and the NA group in splenomegaly degree (3.28±1.95 cm vs 1.92±1.06 cm, P = 0.030), aspartate aminotransferase/alanine aminotransferase ratio [3.15 (0.38-5.93) vs 2.14 (0.26-6.67), P = 0.010], activated partial thromboplastin time (53.27±11.68 s vs 45.06±9.79 s, P = 0.003), and international normalized ratio (1.92±1.35 vs 1.29±0.33, P = 0.001). The SLC25A13 mutation I 851_854del4 was associated with Alb (χ² = 4.76, P = 0.025). Conclusion: As for the children with Alb < 30g/L who are highly suspected of having NICCD, SLC25A13 gene detection and blood/urine mass spectrometry should be performed as early as possible, in order to initiate intervention treatment as soon as possible, prevent and treat complications, and improve prognosis.