PtdIns4P exchange at endoplasmic reticulum-autolysosome contacts is essential for autophagy and neuronal homeostasis.

Inter-organelle contacts enable crosstalk among organelles, facilitating the exchange of materials and coordination of cellular events. In this study, we demonstrated that, upon starvation, autolysosomes recruit Pi4KIIα (Phosphatidylinositol 4-kinase II α) to generate phosphatidylinositol-4-phosphate (PtdIns4P) on their surface and establish endoplasmic reticulum (ER)-autolysosome contacts through PtdIns4P binding proteins Osbp (Oxysterol binding protein) and cert (ceramide transfer protein). We found that the Sac1 (Sac1 phosphatase), Osbp, and cert proteins are required for the reduction of PtdIns4P on autolysosomes. Loss of any of these proteins leads to defective macroautophagy/autophagy and neurodegeneration. Osbp, cert, and Sac1 are required for ER-Golgi contacts in fed cells. Our data establishes a new mode of organelle contact formation - the ER-Golgi contact machinery can be reused by ER-autolysosome contacts by re-locating PtdIns4P from the Golgi apparatus to autolysosomes when faced with starvation.Abbreviations: Atg1: Autophagy-related 1; Atg8: Autophagy-related 8; Atg9: Autophagy-related 9; Atg12: Autophagy-related 12; cert: ceramide transfer protein; Cp1/CathL: cysteine proteinase-1; CTL: control; ER: endoplasmic reticulum; ERMCS: ER-mitochondria contact site; fwd: four wheel drive; GM130: Golgi matrix protein 130 kD; Osbp: Oxysterol binding protein; PG: phagophore; PtdIns4K: phosphatidylinositol 4-kinase; Pi4KIIα: Phosphatidylinositol 4-kinase II α; Pi4KIIIα: Phosphatidylinositol 4-kinase III α; PtdIns4P: phosphatidylinositol-4-phosphate; PR: photoreceptor cell; RT: room temperature; Sac1: Sac1 phosphatase; Stv: starvation; Syx17: Syntaxin 17; TEM: transmission electron microscopy; VAP: VAMP-associated protein.

SARS-CoV-2 Spreads Globally Through the Object-to-Human Transmission of Cross-Border Logistics.

With globalization, the demand for transnational logistics is growing rapidly. However, the object-to-human transmission of SARS-CoV-2 has been reported in transnational logistics production, transportation, storage, sales, and consumption. Every link of transnational logistics has the risk of spreading the COVID-19 pandemic. It is concluded that low temperatures, dry environments, and smooth surfaces are conducive to the long-term survival of SARS-CoV-2 on the surface of transnational goods. Epidemiological investigation and big data analysis show that the object-to-human transmission route of direct contact with contaminated cold chain goods plays a key role in the outbreak and transmission of the COVID-19 pandemic. This may be the most crucial reason for the global spread of SARS-CoV-2 caused by transnational logistics. It is an effective way to prevent the spread of SARS-CoV-2 from object-to-human through transnational logistics by strengthening the management of employees in all aspects of transnational logistics, carrying out comprehensive disinfection and quarantine of and guiding consumers to handle transnational goods properly.

Accurate Interpretation of SARS-CoV-2 Antigen Detection by Immunochromatography.

SARS-CoV-2 is a serious infectious respiratory virus that can cause lung, heart, kidney, and liver damage and even cause death. Early diagnosis of SARS-CoV-2 infection is vital for epidemic prevention and control. At present, the gold standard of COVID-19 diagnosis is nucleic acid detection of SARS-CoV-2. However, the nucleic acid detection of SARS-CoV-2 requires high site requirements and technology requirements, and the detection is time-consuming and cannot fully meet clinical needs. Although SARS-CoV-2 antigen test results cannot be directly used to diagnose COVID-19, positive results can be used for the early triage and rapid management of suspected populations. However, due to the limitations of the methodology itself, the SARS-CoV-2 antigen test is prone to produce false-positive and false-negative results in the process of detection. It is urgent to develop a batch of SARS-CoV-2 antigen reagents based on new detection technology and detection principles to overcome the defects of existing technologies.

Challenges of SARS-CoV-2 Omicron Variant and appropriate countermeasures.

The Omicron (B.1.1.529) variant was first reported in South Africa and rapidly spread worldwide in early November 2021. This caused panic in various countries, so it is necessary to understand Omicron Variant. This paper summarizes omicron variant-related research achievements. Studies have shown that Omicron Variant contains many mutations that make it more infectious and transmissible. At the same time, immune escape is also caused, resulting in reduced efficacy of existing vaccines, increased risk of reinfection, treatment failure or reduction of monoclonal antibody therapies, and detection failure. However, current data indicate that Omicron Variant causes mild clinical symptoms and few severe cases and deaths. Omicron Variant is valid for a range of nonpharmaceutical interventions against SARS-CoV-2. Improving diagnostic accuracy and enabling timely isolation and treatment of diagnosed cases is also critical to interrupting the spread of omicron variants. COVID-19 vaccine boosters could undoubtedly help control Omicron spread and infection. However, developing a vaccine specific to Omicron Variant is also imminent.

Performance and application evaluation of SARS-CoV-2 antigen assay.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid detection is the gold standard for the laboratory diagnosis of coronavirus disease 2019 (COVID-19). However, this method has high requirements for practitioners' skills and testing sites, so it is not easy to popularize and promote the application in places other than large hospitals. In addition, the detection flux of SARS-CoV-2 nucleic acid is small, and the whole detection process takes much time, which cannot meet the actual needs of rapid screening in large quantities. The WHO conditionally approved a batch of SARS-CoV-2 antigen reagents for clinical application to alleviate this contradiction. SARS-CoV-2 antigen detection offers a trade-off among clinical performance, speed and accessibility. With the gradual increase in clinical application, the accumulated clinical data show that the sensitivity and specificity of the SARS-CoV-2 antigen assay are over 80% and 97%, respectively, which can basically meet the requirements of the WHO. However, the sensitivity of the SARS-CoV-2 Antigen Assay among asymptomatic people in low prevalence areas of COVID-19 cannot meet the standard, leading to a large number of missed diagnoses. In addition, the detection ability of SARS-CoV-2 antigen reagent for different SARS-CoV-2 mutant strains differs greatly, especially for those escaping the COVID-19 vaccines. In terms of results interpretation, it is highly reliable to exclude SARS-CoV-2 infection based on the high negative predictive value of the SARS-CoV-2 antigen assay. However, in the low prevalence environment, the probability of false positives of the SARS-CoV-2 antigen assay is high, so the positive results need to be confirmed by the SARS-CoV-2 nucleic acid reagent. The SARS-CoV-2 antigen assay is only a supplement to SARS-CoV-2 nucleic acid detection and can never completely replace it. To date, SARS-CoV-2 nucleic acid detection continues to be the standard laboratory method for COVID-19 diagnosis.

Regulation of lipid homeostasis by the TBC protein dTBC1D22 via modulation of the small GTPase Rab40 to facilitate lipophagy.

The regulation of lipid homeostasis is not well understood. Using forward genetic screening, we demonstrate that the loss of dTBC1D22, an essential gene that encodes a Tre2-Bub2-Cdc16 (TBC) domain-containing protein, results in lipid droplet accumulation in multiple tissues. We observe that dTBC1D22 interacts with Rab40 and exhibits GTPase activating protein (GAP) activity. Overexpression of either the GTP- or GDP-binding-mimic form of Rab40 results in lipid droplet accumulation. We observe that Rab40 mutant flies are defective in lipid mobilization. The lipid depletion induced by overexpression of Brummer, a triglyceride lipase, is dependent on Rab40. Rab40 mutant flies exhibit decreased lipophagy and small size of autolysosomal structures, which may be due to the defective Golgi functions. Finally, we demonstrate that Rab40 physically interacts with Lamp1, and Rab40 is required for the distribution of Lamp1 during starvation. We propose that dTBC1D22 functions as a GAP for Rab40 to regulate lipophagy.

An imbalance of T cell subgroups exists in children with sepsis.

The purpose of this study is to explore the role of different T cell subgroups in the pathogenesis of sepsis in children. Flow cytometry was used to detect the changes in the activation status and the number of T cell subgroups in the peripheral blood of children with sepsis; healthy children were selected as the control group. Compared with healthy children, the number of CD4+ T cells in the peripheral blood of children with sepsis did not change significantly (Z = 1.945, P = 0.052); though the ratio decreased and the median level dropped from 34.6% to 30.7% (Z = 2.257, P = 0.024). However, the number of CD8+ T cells in the blood of children with sepsis increased, and the median level also increased from 0.2 × 109/L to 0.4 × 109/L (Z = -2.404, P = 0.016). In addition, CD3+CD8+HLA-DR + cell level significantly increased, and the median level increased from 4.2% to 24.3% (Z = -5.370, P = 0.000). There was a large heterogeneity in the hospitalization time of sepsis in clinical patients. Compared to patients with a mean hospital stay of 6 days, patients with a median hospital stay of 13 days had a lower CD3+CD4+CD25 + cells percentage, while the percentage of CD3+CD8+HLA-DR+ was higher, resulting in a more apparent increase of CD3+ CD8+HLA-DR+/CD3+CD4+CD25+. Therefore, the failure of CD4+ T cell activation and proliferation, and the excessive activation and proliferation of CD8+ T cells play an important role in the pathogenesis of sepsis. The increase of CD3+CD8+HLA-DR+/CD3+CD4+CD25 + ratio was associated with the extended course of sepsis.

Clinical Significance of Interleukin-6 in the Diagnosis of Sepsis and Discriminating Sepsis Induced by Gram-negative Bacteria.

BACKGROUND: To discuss the clinical significance of interleukin (IL)-6 in the differential diagnosis of sepsis and its capability of differentiating the sepsis induced by Gram-negative bacteria from that induced by Gram-positive bacteria. METHODS: A total of 379 children with sepsis were involved in this study to form the case group, and their C-reactive protein (CRP), procalcitonin (PCT) and IL-6 levels before antibiotics and after recovery were checked. Receiver operating characteristic curve was applied to evaluate the significance of CRP, PCT and IL-6 in the differential diagnosis of sepsis and their capability of differentiating the sepsis induced by Gram-negative bacteria from that induced by Gram-positive bacteria. RESULTS: When these 3 indicators were applied to the differential diagnosis of sepsis, the area under the curve (AUC) of IL-6, PCT and CRP was 0.881, 0.877 and 0.754, respectively. The combination of IL-6 and PCT presented highest diagnostic efficiency. CRP, PCT and IL-6 levels in children with sepsis induced by Gram-negative bacteria were significantly higher than those in children with sepsis induced by Gram-positive bacteria. CONCLUSIONS: CRP, IL-6 and PCT are applicable to the differential diagnosis of sepsis and differentiating the sepsis induced by Gram-negative bacteria from Gram-positive bacteria. Appropriate combinations of these indicators are capable of increasing differential diagnosis efficiency. These indicators can be used as markers of antibiotics usage, but whether they can be used as markers to withdraw antibiotics is still needed to be observed.

Utility of cytokines to predict neonatal sepsis.

BACKGROUND: Sepsis is an important cause of neonatal morbidity and mortality worldwide. Diagnosis and treatment of neonatal sepsis relies on clinical judgment and interpretation of nonspecific laboratory tests. In a prospective cohort, we measured inflammatory cytokines as a potential biomarker for neonatal sepsis. METHODS: Serum inflammatory cytokine levels were evaluated in the early stage of neonatal sepsis and after antimicrobial treatment. Receiver operating characteristic curves assessed the diagnostic value of cytokines. We performed multiple logistic regression analysis to characterize the role of each cytokine independently for infants with culture proven sepsis. RESULTS: C-reactive protein, interleukin (IL)-6, IL-10 and IL-6/IL-10 levels were significantly elevated in neonatal sepsis when compared with the control group and there were 1.4 (95% confidence interval (CI): 1.2-1.5), 4.9 (95% CI: 4.6-5.1), 5.1 (95% CI: 4.5-5.6), and 10.2 (95% CI: 9.2-11.1) fold greater odds, respectively, to predict neonatal sepsis when increased. After effective treatment, median IL-6 (pretreatment value: 263.0 pg/ml and post-treatment value: 7.4 pg/ml) and IL-6/IL-10 levels (pretreatment value: 16.6 and post-treatment value: 1.4) significantly decreased. The areas under the curve for IL-6, IL-10, IL-6/IL-10 and C-reactive protein for differential diagnosis were 0.98, 0.82, 0.90, and 0.88, respectively. CONCLUSION: IL-6 and IL-6/IL-10 outperformed C-reactive protein to diagnose neonatal sepsis. Of the cytokines studied, IL-6 was the most sensitive, whereas IL-6/IL-10 was the most specific predictor of neonatal sepsis.

Haze is an important medium for the spread of rotavirus.

This study investigated whether the rotavirus infection rate in children is associated with temperature and air pollutants in Hangzhou, China. This study applied a distributed lag non-linear model (DLNM) to assess the effects of daily meteorological data and air pollutants on the rotavirus positive rate among outpatient children. There was a negative correlation between temperature and the rotavirus infection rate. The impact of temperature on the detection rate of rotavirus presented an evident lag effect, the temperature change shows the greatest impact on the detection rate of rotavirus approximate at lag one day, and the maximum relative risk (RR) was approximately 1.3. In 2015, the maximum cumulative RR due to the cumulative effect caused by the temperature drop was 2.5. Particulate matter (PM) 2.5 and PM10 were the primary air pollutants in Hangzhou. The highest RR of rotavirus infection occurred at lag 1-1.5 days after the increase in the concentration of these pollutants, and the RR increased gradually with the increase in concentration. Based on the average concentrations of PM2.5 of 53.9 µg/m(3) and PM10 of 80.6 µg/m(3) in Hangzhou in 2015, the cumulative RR caused by the cumulative effect was 2.5 and 2.2, respectively. The current study suggests that temperature is an important factor impacting the rotavirus infection rate of children in Hangzhou. Air pollutants significantly increased the risk of rotavirus infection, and dosage, lag and cumulative effects were observed.

Clinical Value of Assessing Cytokine Levels for the Differential Diagnosis of Bacterial Meningitis in a Pediatric Population.

We performed a prospective observational study to evaluate the utility of measuring inflammatory cytokine levels to discriminate bacterial meningitis from similar common pediatric diseases. Inflammatory cytokine levels and other cerebrospinal fluid (CSF) physicochemical indicators were evaluated in 140 patients who were diagnosed with bacterial meningitis via microbiological culture or PCR assay. The CSF concentrations of interleukin (IL)-6 and IL-10, CSF/blood IL-6 and IL-10 ratios, CSF white blood cell count, and CSF micro total protein were significantly elevated in bacterial meningitis patients compared with healthy children or patients with viral encephalitis, epilepsy, or febrile convulsions (P < 0.001). The area under the curve values for CSF concentrations of IL-6 and IL-10, CSF/blood IL-6 and IL-10 ratios, CSF white blood cell count, and CSF micro total protein to identify bacterial meningitis episodes by receiver-operating characteristic analysis were 0.988, 0.949, 0.995, 0.924, 0.945, and 0.928, respectively. The area under the curve for the combination of CSF IL-6 and CSF/blood IL-6 ratio was larger than that for either parameter alone, and the combination exhibited enhanced specificity and positive predictive value. After effective meningitis treatment, CSF IL-6 levels dropped significantly. These results suggest that CSF IL-6 and CSF/blood IL-6 ratio are good biomarkers in discriminating bacterial meningitis. Evaluating CSF IL-6 and CSF/blood IL-6 ratio in combination can improve diagnostic efficiency. Additionally, CSF IL-6 levels can be used to monitor the effects of bacterial meningitis treatment.

A Comprehensive Assessment of the Value of Laboratory Indices in Diagnosing Kawasaki Disease.

OBJECTIVE: Kawasaki disease (KD) is the primary cause of heart disease among children, but because its clinical symptoms are nonspecific, it is difficult to diagnose. The purpose of this study was to evaluate laboratory indices for possible use in the early diagnosis of KD and to determine which indices are predictive of a response to intravenous immunoglobulin (IVIG) and can be used to monitor the effects of treatment. METHODS: Three hundred thirty KD patients, 330 age-matched children with KD-like febrile disease, and 330 age-matched healthy children (controls) were enrolled in this prospective study. Levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and cytokines were determined in all study subjects. RESULTS: In the derivation cohort, 181 patients in the KD group were compared with 181 patients in the KD-like febrile group. The following indices were found to be useful in the diagnosis of KD: NT-proBNP (area under the curve [AUC] 0.923), ESR (AUC 0.909), CRP (AUC 0.834), and interleukin-6 (IL-6; AUC 0.678). The diagnostic efficiency of each index demonstrated in the derivation cohort was repeated in the 149 KD patients in the validation cohort. There were significant differences in NT-proBNP levels between IVIG-responsive KD patients (n = 270) and IVIG-nonresponsive KD patients (n = 60), with higher NT-proBNP levels in IVIG-nonresponsive KD patients. The NT-proBNP level can effectively distinguish IVIG-responsive KD patients from IVIG-nonresponsive patients, and its AUC was 0.73. There were also significant differences in the NT-proBNP levels before and after treatment, with a significant decline after treatment. CONCLUSION: Serum levels of NT-proBNP can be used in the diagnosis of KD, the prediction of a patient's sensitivity to IVIG treatment, and the monitoring of the effects of IVIG treatment, but more attention must be paid to the scope of its application.

Epidemiological characteristics and immune status of children with Respiratory Syncytial Virus.

Respiratory Syncytial Virus (RSV) infections are the dominant cause of pneumonia in children. In order to determine the epidemiological characteristics and immune status of children with Respiratory Syncytial Virus, a prospective study was performed among patients with RSV infection. Comparisons between RSV pneumonia group and normal control group, RSV pneumonia group had lower IL-2 (median levels, pg/ml: 3.8 vs. 5.1, P < 0.01), and higher IL-4 (median levels, pg/ml: 3.2 vs. 2.4, P < 0.01), IL-10 (median levels, pg/ml: 12.2 vs. 2.3, P < 0.01), and IFN-γ (median levels, pg/ml: 13.4 vs. 4.6, P < 0.01). The level of IgE among pneumonia patients caused by RSV increased sharply (median levels, mg/L: 48.1 vs. 8.8, P < 0.01). Another amazing finding is that after birth, the degree of IgE of the children infected by RSV increases gradually with age. This effect is at its peak in 0.6 years old. The IgE and eosinophil levels were higher when patients suffered from RSV pneumonia with wheeze (IgE median levels, IU/ml: with wheeze: 72.74 vs. without wheeze: 11.5, P < 0.05; eosinophil median levels, ×10(9) /l: with wheeze: 0.21 vs. without wheeze: 0.05, P < 0.05). The main morbidity crowd is the children under the age of 1 year old. The downregulation of IL2 and the upregulation of IL-4, IL-10, IFN-γ, and IgE happen after RSV infection.

Relationship between immune parameters and organ involvement in children with Henoch-Schonlein purpura.

Henoch-Schonlein purpura (HSP) is the most common type of connective tissue diseases which increasingly occurs in children in recent years and its pathogenesis remains unclear. In order to explore the immune parameters and underlying pathogenesis mechanism of children with HSP, the study involved 1232 patients with HSP having different clinical symptoms and their laboratory indicators were evaluated. Th1/Th2 imbalance and overactivity of Th2 cells can cause increase in the synthesis and release of immunoglobulins in children with HSP. The number of red blood cells and white blood cells in urine was directly proportional to the level of IgA and inversely proportional to the level of serum complements (C3 and C4). Activation of these complements caused by immunoglobulin in patients with HSP plays an important role in renal injury. The urinary protein content in children with HSP along with proteinuria was positively correlated with IgE level, and IgE mediated type 1 hypersensitivity can cause increase in capillary permeability and weakened the charge barrier; hence, it could be considered as one of the causes of proteinuria in HSP. Additionally, the NK cells percentage was reduced and impaired immune function of NK cells were related to the immune injury of the digestive tract and kidney.

Mycoplasma pneumoniae infection in children is a risk factor for developing allergic diseases.

Mycoplasma pneumoniae (MP) infection is the dominant cause of pneumonia in children. We sought to determine the relationship between MP infection and secondary allergic disease and to clarify the associated mechanisms of inflammatory response. A prospective study was performed among 1330 patients diagnosed with pneumonia to investigate the patient immune status by determining the correlation between MP infection, immunoglobulin E (IgE) levels, and a spectrum of associated serum cytokines. Serum IgE, IL-4, IL-6, and IL-10 levels for MPP patients in the acute phase were obviously higher than those in the recovery phase (P < 0.01). MPP patients with allergic conditions had increased serum IgE levels and increased IL-4/INF- γ ratio, and IgE and Eosinophil Cationic Protein were further elevated in patients who eventually developed secondary asthma changes. Patients with severe pneumonia and high clinical pulmonary infection scores presented higher levels of IL-4 and IL-5 in serum than those with low scores (P < 0.01). The proportion of CD4+ and CD8+ T cells that secreted IL-4 was significantly increased in MPP patients with elevated IgE. Our data demonstrate a significant correlation between MP infection and IgE levels, which is associated with a Th1/Th2 cytokine imbalance.

The clinical application value of cytokines in treating infectious diseases.

We performed a prospective study to evaluate the abilities of inflammatory cytokines to rule out the potential risk of sepsis and intracranial infection and to estimate the function of inflammatory cytokines in discriminating Gram-negative bacteria from Gram-positive ones through ROC analysis. During the course of the study, Levels of serum inflammatory cytokines were measured by flow cytometry at the onset of diseases of patients who suffered from sepsis or intracranial infection. A total of 299 cases of sepsis and 43 cases of intracranial infection were observed during the study. It is noticed that there is no difference of inflammatory cytokine levels between sepsis group and intracranial infection group. The area under ROC curve (AUC) of cytokines, such as IL-2, IL-6 and IL-10 were 0.901, 0.86, 0.888, respectively, which was employed to rule out the diseases of sepsis and intracranial infection. Through comparisons with the patients who were infected by Gram-positive bacteria or Gram-negative ones, it is estimated that IL-6 and IL-10 sharply elevated in patients with Gram-negative bacteria infection (median levels, pg/mL: IL-6: 116.6 vs. 25.4, P = 0.000; IL-10: 13.7 vs. 6.3, P = 0.000). Additionally, IL-2 significantly decreased when patients suffered from Gram-negative bacteria infection (median levels, pg/mL: IL-2: 2.2 vs. 2.7, P = 0.031). The AUCs for detecting cytokines, including IL-2, IL-10 and LOGREGR.Pred_IL-2+IL-10 were 0.581 (95% CI, 0.526 to 0.634), 0.661 (95% CI, 0.608 to 0.712) and 0.735 (95% CI, 0.685 to 0.782), respectively, which was used to evaluate the function of inflammatory cytokines in discriminating Gram-negative bacteria from Gram-positive ones infection. This paper indicates that IL-2, IL-6 and IL-10 are effective biomarkers to rule out sepsis and intracranial infection. Additionally, the combination of IL-2 and IL-10 is an effective biomarkers to diagnose whether patients afflicted by Gram-negative bacteria.