Procalcitonin as a Diagnostic Marker in Patients with Infectious Diseases

Background: Procalcitonin levels have been shown to indicate severity of a disease, but there have been few reports about interpretation of procalcitonin levels between different diseases. This study was therefore carried out to investigate the usefulness of procalcitonin for clinical diagnosis, and for discriminating between bacterial and viral infection, between cystitis and pyelonephritis, and between acute upper respiratory inflammation and pneumonia.Methods: Among patients with the primary complaint of fever who were treated, either hospitalized or as out-patients, at Saitama Medical University Hospital during a 5-year period from August 1, 2012, to July 31, 2017, the potential subjects for this study were the 362 patients, consisting of 191 males and 171 females, with whom procalcitonin was measured. The subjects with whom comparative evaluation was carried out were the 205 with whom the final diagnoses were diseases, these being infectious diseases, malignancies, collagen diseases, and benign tumors with 176, 12, 11 and 6 patients, respectively. The remaining patients were excluded from the study, these consisting of 150 patients with whom the final diagnosis was merely symptoms such as headache, or was a condition not covered by internal medicine, such as traumas; and 7 patients whose diagnoses were unknown.Results: Procalcitonin levels in patients with infectious diseases were significantly higher (p < 0.05) than in patients with malignant tumors, collagen diseases, or benign tumors. Comparison between different diseases showed significant differences (p < 0.05) between pyelonephritis and cystitis, and between bacterial pneumonia and acute upper respiratory inflammation.Conclusions: Procalcitonin was significantly elevated in patients with bacterial infection. Significant differences in procalcitonin level were found between pyelonephritis and cystitis, and between bacterial pneumonia and acute upper respiratory inflammation, so procalcitonin is considered to be useful for discrimination between these.

Pharmacologic Activities of Plant-Derived Natural Products on Respiratory Diseases and Inflammations

Respiratory inflammation is caused by an air-mediated disease induced by polluted air, smoke, bacteria, and viruses. The COVID-19 pandemic is also a kind of respiratory disease, induced by a virus causing a serious effect on the lungs, bronchioles, and pharynges that results in oxygen deficiency. Extensive research has been conducted to find out the potent natural products that help to prevent, treat, and manage respiratory diseases. Traditionally, wider floras were reported to be used, such as Morus alba, Artemisia indica, Azadirachta indica, Calotropis gigantea, but only some of the potent compounds from some of the plants have been scientifically validated. Plant-derived natural products such as colchicine, zingerone, forsythiaside A, mangiferin, glycyrrhizin, curcumin, and many other compounds are found to have a promising effect on treating and managing respiratory inflammation. In this review, current clinically approved drugs along with the efficacy and side effects have been studied. The study also focuses on the traditional uses of medicinal plants on reducing respiratory complications and their bioactive phytoconstituents. The pharmacological evidence of lowering respiratory complications by plant-derived natural products has been critically studied with detailed mechanism and action. However, the scientific validation of such compounds requires clinical study and evidence on animal and human models to replace modern commercial medicine.

Attenuated asthma phenotype in mice with a fetal-like antigen receptor repertoire

We hypothesized that the scarcity of N-nucleotides might contribute to the inability of the neonate to mount a robust allergic immune response. To test this, we used terminal deoxyribunucleotidyl Transferase deficient (TdT−/−) mice, which express “fetal-like” T cell receptor and immunoglobulin repertoires with largely germline-encoded CDR3 regions. Intraperitoneal sensitization was followed by aerosol provocation with either PBS or the allergen OVA in both TdT−/− mice and wild-type mice to develop allergic respiratory inflammation. The effects of this procedure were investigated by lung function test, immunological analysis of serum and brochoalveolar lavage. The local TH2 cytokine milieu was significantly attenuated in TdT−/− mice. Within this group, the induction of total IgE levels was also significantly reduced after sensitization. TdT−/− mice showed a tendency toward reduced eosinophilic inflow into the bronchial tubes, which was associated with the elimination of respiratory hyperreactivity. In conclusion, in a murine model of allergic airway inflammation, the expression of fetal-like antigen receptors was associated with potent indications of a reduced ability to mount an asthma phenotype. This underlines the importance of somatically-generated antigen-receptor repertoire diversity in type one allergic immune responses and suggests that the fetus may be protected from allergic responses, at least in part, by controlling N addition.

A suitable murine model for studying respiratory coronavirus infection and therapeutic countermeasures in BSL-2 laboratories

Several animal models are being used to explore important features of COVID-19, nevertheless none of them recapitulates all aspects of the disease in humans. The continuous refinement and development of other options of in vivo models are opportune, especially ones that are carried out at BSL-2 (Biosafety Level 2) laboratories. In this study, we investigated the suitability of the intranasal infection with the murine betacoronavirus MHV-3 to recapitulate multiple aspects of the pathogenesis of COVID-19 in C57BL/6J mice. We demonstrate that MHV-3 replicated in lungs 1 day after inoculation and triggered respiratory inflammation and dysfunction. This MHV-model of infection was further applied to highlight the critical role of TNF in cytokine-mediated coronavirus pathogenesis. Blocking TNF signaling by pharmacological and genetic strategies greatly increased the survival time and reduces lung injury of MHV-3-infected mice. In vitro studies showed that TNF blockage decreased SARS-CoV-2 replication in human epithelial lung cells and resulted in the lower release of IL-6 and IL-8 cytokines beyond TNF itself. Taken together, our results demonstrate that this model of MHV infection in mice is a useful BSL-2 screening platform for evaluating pathogenesis for human coronaviruses infections, such as COVID-19.

P058 Persistence of neutrophil abnormalities in COVID-19 convalescence

Background/Aims Patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may develop acute respiratory inflammation, due to an exaggerated immune response and some develop chronic complications. Neutrophils play a major role in the pathology of inflammatory diseases and have been shown to contribute to lung and vascular damage in COVID-19. Our aim was to establish a relationship between neutrophil phenotype and disease severity and to determine whether neutrophil abnormalities persist in convalescent patients. Methods Peripheral blood samples were obtained from acute COVID-19 patients (n = 74), follow-up (FU) patients discharged following inpatient admission (n = 56), a median of 87 days after discharge, and healthy controls (HCs, n = 22). Patients were stratified by disease severity based on inspired oxygen (FiO2) and admission to intensive care (ICU). Neutrophils were isolated from whole blood by negative selection for phenotyping and functional analysis. PBMC Isolation Tubes were used to quantify and phenotype low density neutrophils (LDNs) within the PBMC fraction. For quantification of reactive oxygen species (ROS) production, isolated neutrophils were incubated with a ROS reactive dye, DHR-123 and stimulated with PMA. All samples were stained and fixed prior to analysis by flow cytometry. Results There was a marked increase in neutrophils expressing the activation and degranulation markers, CD64 (P &lt; 0.0001) and CD63 (P &lt; 0.0001) and a reduction in neutrophils expressing the maturity markers, CD10 (P &lt; 0.0005) and CD101 (P &lt; 0.0005) in patients with acute COVID-19 compared to HCs. Increased frequency of neutrophils expressing CD64 (P &lt; 0.005), CD63 (P &lt; 0.01) and expressing decreased CD101 (P &lt; 0.0001) were also detected in FU patients compared to HCs. Notably, 42.3 ± 4.4% of neutrophils were CD101lo in FU patients, compared to 29.0 ± 3.7% in acute patients and 9.6 ± 4.1% in HCs. These changes were most apparent in FU patients recovering from severe COVID-19 compared to mild or moderate disease. The frequency of LDNs in PBMCs from acute patients was significantly higher than HCs (P &lt; 0.0001), and correlated with disease severity. Similarly, the frequency of LDNs in FU patients was significantly higher than in HCs (P &lt; 0.0005). We found a trend towards higher basal ROS production in acute and FU patients, but a blunted response to PMA stimulated ROS production in neutrophils from acute patients versus HCs (P &lt; 0.0001). Impaired ROS production persisted in FU patients compared to HCs (P &lt; 0.01). Conclusion Circulating neutrophils in acute COVID-19 have an altered phenotype and comprise immature and activated cells. This altered phenotype persisted in convalescence and may contribute to the persistence of symptoms and an increased susceptibility to subsequent infections. Future work will aim to investigate the functional implications of these findings. Disclosure T.O. Williams: None. V. Kästele: None. E.R. Mann: None. S.B. Knight: None. M. Menon: None. C. Jagger: None. S. Khan: None. J.E. Konkel: None. T.N. Shaw: None. M. Rattray: Consultancies; M.R. has a paid consultancy with AstraZeneca. L. Pearmain: None. A. Horsley: None. A. Ustianowski: None. I. Prise: None. N.D. Bakerly: None. P.M. Dark: None. G.M. Lord: Corporate appointments; G.M.L. is cofounder and scientific advisory board member of Gritstone Oncology Inc., which is a public company that develops therapeutic vaccines (primarily for the treatment of cancer). A. Simpson: None. T. Felton: None. L. Ho: None. M. Feldmann: None. I. Bruce: None. J.R. Grainger: None. T. Hussell: None.

DIAGNOSIS DETECTION OF ACUTE RESPIRATOR INFECTION WITH FORWARD CHAINING METHOD

Many acute respiratory infections or ARI are caused by viruses that attack the nose, trachea (breathing tube), or the lungs. It can be said that ARI is caused by inflammation that disrupts a person's breathing process. If not treated quickly, ARI can spread to all respiratory systems and prevent the body from getting proper oxygen, moreover it can cause the loss of a person's life. This research aims to diagnose ARI as an early step in practicing artificial intelligence in medicine, designing and apply an expert system that can diagnose ARI. The procedure used in this study uses forward chaining with tracking that begins with input data, and then creates a diagnosis or solution. The expert system used to diagnose acute respiratory inflammation uses the Forward chaining procedure with a data-driven approach, in this approach tracking starts from input data, and then seeks to draw conclusions, so that it can be used. diagnose the type of disease associated with the ARD disease experienced by showing the existing signs.

Attenuated Asthma Phenotype in Mice With a Fetal-Like Antigen Receptor Repertoires

We hypothesized that the scarcity of N-nucleotides might contribute to the inability of the neonate to mount a robust allergic immune response. To test this, we used terminal deoxyribunucleotidyl Transferase deficient (TdT-/-) mice, which express “fetal like” T cell receptor and immunoglobulin repertoires with largely germline-encoded CDR3 regions.Intraperitoneal sensitization was followed by aerosol provocation with either PBS or the allergen OVA in both Tdt-/- mice and wild-type mice to develop allergic respiratory inflammation. The effects of this procedure were investigated by lung function test, immunological analysis of serum and brochoalveolar lavage. The local TH2 cytokine milieu was significantly attenuated in Tdt-/- mice. Within this group, the induction of total IgE levels was also significantly reduced after sensitization. Tdt-/- mice showed a reduced eosinophilic inflow into the bronchial tubes, which was associated with the elimination of respiratory hyperreactivity. In conclusion, in a murine model of allergic airway inflammation, the expression of fetal-like antigen receptors was associated with a reduced ability to mount an asthma phenotype. This underlines the importance of somatically-generated antigen-receptor repertoire diversity in type one allergic immune responses and suggests that the fetus may be protected from allergic responses, at least in part, by controlling N addition.

Novel investigation of perovskite membrane based electrochemical nitric oxide control phenomenon

The combustion of hydrocarbon fuels within the automotive industry results in harmful and reactive incomplete combustion byproducts. Specifically, nitric oxide emissions (NO) lead to increased smog, acid rain, climate change, and respiratory inflammation within the population [Nitrogen Dioxide | American Lung Association]. Current methods for treating combustion exhaust include the catalytic converter in conjunction with nitrogen oxide traps. However, there is no active, continuous reduction method that does not require restrictions on the combustion environment (Hirata in Catal Surv Asia 18:128–133, 2014). Here, a small voltage potential oscillation across a newly designed electro-chemical catalytic membrane significantly reduces NO emissions. A ceramic membrane consisting of two dissimilar metal electrodes, sandwiching a dielectric layer, is able to achieve an NO reduction in excess of 2X that of a platinum group metal (PGM) three way catalytic converter. An analysis of the exhaust effluent from the membranes indicates N2O as a precursor to N2 and O2 formation, without the introduction of ammonia (NH3), during the reaction of NO indicating a divergence from current literature. Our results demonstrate how an oscillatory electric potential on a catalytic surface may alter anticipated reaction chemistry and interaction between the catalytic surface and fluid flow.