Improved accuracy of etiological diagnosis of spinal infection by metagenomic next-generation sequencing.

Currently, the use of metagenomic next-generation sequencing (mNGS), a new approach to identify organisms in infectious diseases, is rarely reported in the diagnosis of spinal infection. This study aimed to evaluate the potential value of mNGS in etiological diagnosis of spinal infection. In this retrospective study, the clinical data of patients with suspected spinal infection were collected by electronic medical records. Specimens obtained from each patient were tested via mNGS assay and other conventional microbiological tests (CMTs). The sensitivity and specificity of mNGS and CMTs were calculated using the final clinical diagnosis as the golden standard. In total, 108 patients were eligible for the study, with the mean length of stay of 42.8 days. Regarding the overall identification of pathogens, mNGS exhibited a better performance than CMTs, and several nontuberculous mycobacteria, fungi, and bacteria were newly discovered. In the diagnosis of spinal infection, the sensitivity, specificity, and area under the curve of mNGS were 90.72%, 81.82%, and 0.89, respectively, which were all higher than 52.17%, 56.25%, and 0.72 of the CMTs. At hospital discharge, the C-reactive protein, erythrocyte sedimentation rate, and white blood cell count of patients significantly decreased compared with hospitalization (all p < 0.05), and 88.89% showed good outcomes. These findings may suggest that mNGS has a better diagnostic accuracy in pathogenic identification of patients with suspected spinal infection, and patients treated with NGS-guided antimicrobial therapy mostly seem to have good outcomes.

Human endogenous retrovirus K in the respiratory tract is associated with COVID-19 physiopathology.

BACKGROUND: Critically ill 2019 coronavirus disease (COVID-19) patients under invasive mechanical ventilation (IMV) are 10 to 40 times more likely to die than the general population. Although progression from mild to severe COVID-19 has been associated with hypoxia, uncontrolled inflammation, and coagulopathy, the mechanisms involved in the progression to severity are poorly understood. METHODS: The virome of tracheal aspirates (TA) from 25 COVID-19 patients under IMV was assessed through unbiased RNA sequencing (RNA-seq), and correlation analyses were conducted using available clinical data. Unbiased sequences from nasopharyngeal swabs (NS) from mild cases and TA from non-COVID patients were included in our study for further comparisons. RESULTS: We found higher levels and differential expression of human endogenous retrovirus K (HERV-K) genes in TA from critically ill and deceased patients when comparing nasopharyngeal swabs from mild cases to TA from non-COVID patients. In critically ill patients, higher HERV-K levels were associated with early mortality (within 14 days of diagnosis) in the intensive care unit. Increased HERV-K expression in deceased patients was associated with IL-17-related inflammation, monocyte activation, and an increased consumption of clotting/fibrinolysis factors. Moreover, increased HERV-K expression was detected in human primary monocytes from healthy donors after experimental SARS-CoV-2 infection in vitro. CONCLUSION: Our data implicate the levels of HERV-K transcripts in the physiopathology of COVID-19 in the respiratory tract of patients under invasive mechanical ventilation. Video abstract.

[Clinical study on modified Topping-off technology in the treatment of multiple lumbar degenerative diseases].

OBJECTIVE: To explore the clinical effect of the modified Topping-off technique in the treatment of multiple lumbar degenerative diseases. METHODS: From October 2019 to May 2020, 42 patients who underwent modified Topping-off operation (modified Topping-off group) and 42 patients who underwent multilevel total laminectomy and interbody fusion with screw rod system internal fixation (whole laminectomy group) were observed and analyzed. There were 15 males and 27 females in the modified Topping-off group, aged from 28 to 80 years old, with an average of (59.57±11.85)years old. There were 14 males and 28 females in the whole laminectomy group, aged from 45 to 82 years old, with an average of (64.26±9.19) years old. Visual analogue scale (VAS) and Oswestry Disability Index (ODI) were evaluated before operation, 1 week, 6 weeks and 12 weeks after operation. The intraoperative blood loss, incision length, operation time, postoperative drainage, weight-bearing time, hospitalization time, intervertebral space height, intervertebral foramen height and lumbar mobility were statistically analyzed. RESULTS: All patients were followed up for 12 weeks. The intraoperative blood loss and postoperative drainage in the modified Topping-off group were significantly less than those in the whole lamina group (P<0.05). The incision length, operation time, weight-bearing time and hospital stay in the modified Topping-off group were shorter than those in the whole lamina group(P<0.05). There were significant differences in intervertebral space height, intervertebral foramen height and lumbar mobility between the two groups at 12 weeks after operation(P<0.05). The modified Topping-off group had significantly lower VAS 1, 6, 12 weeks after operation and ODI 12 weeks after operation compared with rhose before operation. The VAS at 1, 6, 12 weeks in the whole lamina group were significantly lower those that before operation(P<0.05). The ODI at 12 weeks in the whole lamina group were significantly lower than those before operation(P<0.01). There were significant differences in VAS scores between the two groups at 1 week, 6 weeks and 12 weeks after operation(P<0.01). There was significant difference in ODI between the two groups 12 weeks after operation(P<0.01). CONCLUSION: The application of modified Topping-off technique in the treatment of multi segmental lumbar degenerative diseases can reduce the total length of fusion segments, avoid or slow down the degeneration of adjacent segments, and has a positive effect on maintaining the normal movement of the spine.

Solitary bone plasmacytoma of spine with involvement of adjacent disc space: A case report.

RATIONALE: Solitary bone plasmacytoma (SBP) is a rare manifestation of plasma cell tumor. Although axial skeleton is the most frequently affected site of SBP, adjacent disc space involvement is rare. Herein we report a case of SBP in thoracic vertebra with involvement of adjacent disc space. PATIENT CONCERNS: A 57-year-old male presented with a 2-year history of intermittent back pain with activity. The patient's back pain intensity with activity was a score of 5 of the 10-point visual analog scale). DIAGNOSES AND INTERVENTION: The patient underwent a posterior fusion procedure from T6 to T10, and an open biopsy of the vertebral lesion confirmed that final diagnosis of SBP. The patient received postoperative radiotherapy with a total of 4000 Gy to the T7-T9 vertebral levels over a 20-day period. OUTCOMES: Following radiotherapy, the patient's pain intensity was reduced to the visual analog scale score of 1 at the 6-month follow-up. LESSONS: SBP lacks typical clinical symptoms, and the accurate diagnosis before clinical intervention remains challenging. Due to the disc involvement, SBP often manifests as spinal infection. Hence, differential diagnosis in spinal lesions involving the disc should include SBP.

Whole-Genome-Based Helicobacter pylori Geographic Surveillance: A Visualized and Expandable Webtool.

Helicobacter pylori exhibit specific geographic distributions that are related to clinical outcomes. Despite the high infection rate of H. pylori throughout the world, the genetic epidemiology surveillance of H. pylori still needs to be improved. This study used the single nucleotide polymorphisms (SNPs) profiling approach based on whole genome sequencing (WGS) to facilitate genomic population analyses of H. pylori and encourage the dissemination of microbial genotyping strategies worldwide. A total number of 1,211 public H. pylori genomes were downloaded and used to construct the typing tool, named HpTT (H. pylori Typing Tool). Combined with the metadata, we developed two levels of genomic typing, including a continent-scale and a country scale that nested in the continent scale. Results showed that Asia was the largest isolate source in our dataset, while isolates from Europe and Oceania were comparatively more widespread. More specifically, Switzerland and Australia are the main sources of widespread isolates in their corresponding continents. To integrate all the typing information and enable researchers to compare their dataset against the existing global database easily and rapidly, a user-friendly website (https://db.cngb.org/HPTT/) was developed with both genomic typing tools and visualization tools. To further confirm the validity of the website, ten newly assembled genomes were downloaded and tested precisely located on the branch as we expected. In summary, the H. pylori typing tool (HpTT) is a novel genomic epidemiological tool that can achieve high-resolution analysis of genomic typing and visualizing simultaneously, providing insights into the genetic population structure, evolution analysis, and epidemiological surveillance of H. pylori.

Genetic Evidence and Host Immune Response in Persons Reinfected with SARS-CoV-2, Brazil.

The dynamics underlying severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection remain poorly understood. We identified a small cluster of patients in Brazil who experienced 2 episodes of coronavirus disease (COVID-19) in March and late May 2020. In the first episode, patients manifested an enhanced innate response compared with healthy persons, but neutralizing humoral immunity was not fully achieved. The second episode was associated with different SARS-CoV-2 strains, higher viral loads, and clinical symptoms. Our finding that persons with mild COVID-19 may have controlled SARS-CoV-2 replication without developing detectable humoral immunity suggests that reinfection is more frequent than supposed, but this hypothesis is not well documented.

The inhibition of MARK2 suppresses cisplatin resistance of osteosarcoma stem cells by regulating DNA damage and repair.

OBJECTIVE: This study aims to explore the role of MARK2 in chemotherapeutic resistance and potential mechanism within cisplatin resistance models of CD133+ MG-63 and MNNG/HOS cells. METHODS: CD133- and CD133+ MG-63 and MNNG/HOS cells were differentiated and obtained by MACS(Magnetic bead sorting). Cell activity was determined by CCK-8 assay. siRNA was employed to down regulate the Microtubule Affinity Regulated Kinase 2 (MARK2) expression. Immunofluorescence detection and RT-qPCR were used to measure the expressions of MARK2 and DNA-PKcs at both protein and mRNA levels. Western blot was applied to test the levels of MARK2, γH2AX (S139), DNA-PKcs, Phospho-PI3 Kinase p85 (Tyr458), Akt, phospho-Akt (T308) antibodies, mTOR, phospho-mTOR (Ser2448). RESULTS: Compared with CD133- MG-63 cells, CD133+ MG-63 cells showed significantly strong cisplatin resistance, with high levels of MARK2, DNA-PKcs and potent DNA damage repair ability (p<0.05). Down regulation of MARK2 reduced the cisplatin resistance of CD133+ MG-63 cells, with deceasing expression of DNA-PKcs (p<0.05). PI3K/Akt/mTOR pathway was potentially activated in CD133+ MG-63 cells, and involved in the cisplatin resistance of MG-63 cells. The similar results were observed in CD133+ MNNG/HOS cells. The reduction of MARK2 retarded the activity of PI3K/Akt/mTOR pathway and further impeded the cisplatin resistance in CD133+ MG-63 and MNNG/HOS cell. CONCLUSION: Our data suggested that MARK2 was related to cisplatin resistance in CD133+ MG-63 and MNNG/HOS cells. The decrease of MARK2 restricted the cisplatin resistance of CD133+ MG-63 and MNNG/HOS cells by down regulating the expression of DNA dependent protein kinase catalytic subunit (DNA-PKcs) and inhibiting activity of PI3K/Akt/mTOR signaling pathway, which provides new clues for the osteosarcoma chemotherapy strategy.

Diagnosis of Sepsis with Cell-free DNA by Next-Generation Sequencing Technology in ICU Patients.

BACKGROUND AND AIMS: Bacteremia is a common serious manifestation of disease in the intensive care unit (ICU), which requires quick and accurate determinations of pathogens to select the appropriate antibiotic treatment. To overcome the shortcomings of traditional bacterial culture (BC), we have adapted next-generation sequencing (NGS) technology to identify pathogens from cell-free plasma DNA. METHODS: In this study, 78 plasma samples from ICU patients were analyzed by both NGS and BC methods and verified by PCR amplification/Sanger sequencing and ten plasma samples from healthy volunteers were analyzed by NGS as negative controls to define or calibrate the threshold of the NGS methodology. RESULTS: Overall, 1578 suspected patient samples were found to contain bacteria or fungi by NGS, whereas ten patients were diagnosed by BC. Seven samples were diagnosed with bacterial or fungal infection both by NGS and BC. Among them, two samples were diagnosed with two types of bacteria by NGS, whereas one sample was diagnosed with two types of bacteria by BC, which increased the detectability of bacteria or fungi from 11 with BC to 17 with NGS. Most interestingly, 14 specimens were also diagnosed with viral infection by NGS. The overall diagnostic sensitivity was significantly increased from 12.82% (10/78) by BC alone to 30.77% (24/78) by NGS alone for ICU patients, which provides more useful information for establishing patient treatment plans. CONCLUSION: NGS technology can be applied to detect bacteria in clinical blood samples as an emerging diagnostic tool rich in information to determine the appropriate treatment of septic patients.