Correction: Serial measurement of cytokines strongly predict COVID-19 outcome.

[This corrects the article DOI: 10.1371/journal.pone.0260623.].

Serial measurement of cytokines strongly predict COVID-19 outcome.

PURPOSE: Cytokines are major mediators of COVID-19 pathogenesis and several of them are already being regarded as predictive markers for the clinical course and outcome of COVID-19 cases. A major pitfall of many COVID-19 cytokine studies is the lack of a benchmark sampling timing. Since cytokines and their relative change during an infectious disease course is quite dynamic, we evaluated the predictive value of serially measured cytokines for COVID-19 cases. METHODS: In this single-center, prospective study, a broad spectrum of cytokines were determined by multiplex ELISA assay in samples collected at admission and at the third day of hospitalization. Appropriateness of cytokine levels in predicting mortality were assessed by receiver-operating characteristic (ROC) analyses for both sampling times in paralel to conventional biomarkers. RESULTS: At both sampling points, higher levels of IL-6, IL-7, IL-10, IL-15, IL-27 IP-10, MCP-1, and GCSF were found to be more predictive for mortality (p<0.05). Some of these cytokines, such as IL-6, IL-10, IL-7 and GCSF, had higher sensitivity and specificity in predicting mortality. AUC values of IL-6, IL-10, IL-7 and GCSF were 0.85 (0.65 to 0.92), 0.88 (0.73 to 0.96), 0.80 (0.63 to 0.91) and 0.86 (0.70 to 0.95), respectively at hospital admission. Compared to hospital admission, on the 3rd day of hospitalization serum levels of IL-6 and, IL-10 decreased significantly in the survivor group, unlike the non-survivor group (IL-6, p = 0.015, and IL-10, p = 0.016). CONCLUSION: Our study results suggest that single-sample-based cytokine analyzes can be misleading and that cytokine levels measured serially at different sampling times provide a more precise and accurate estimate for the outcome of COVID-19 patients.

Development of Interleukin-2 Loaded Chitosan-Based Nanogels Using Artificial Neural Networks and Investigating the Effects on Wound Healing in Rats.

The aim of this study was to develop and characterize rh- IL-2 loaded chitosan-based nanogels for the healing of wound incision in rats. Nanogels were prepared using chitosan and bovine serum albumin (BSA) by ionic gelation method and high temperature application, respectively. Particle size, zeta potential, and polydispersity index were measured for characterization of nanogels. The morphology of nanogels was examined by using SEM and AFM. The IL-2 loading capacity of nanogels was determined using ELISA method. In vitro release of IL-2 from nanogels was performed using Franz diffusion cells. Artificial neural network (ANN) models were developed using selected input parameters (stirring rate, chitosan%, BSA%, TPP%) where particle size was an output parameter for IL-2 free nanogels. Wound healing effect of IL-2 loaded chitosan-TPP nanogel was evaluated by determining the malondialdehyde (MDA) and glutathione (GSH) levels of wound tissues in rats. The particle size of IL-2 loaded chitosan-TPP nanogels was found to be larger than that of IL-2 loaded BSA-based chitosan nanogels. Drug loading capacity of nanogels was found 100% ± 0.010 for both nanogels. IL-2 was released slowly after the initial burst effect. According to SEM and AFM imaging, BSA-chitosan nanogel particles were of nanometer size and presented a swelling tendency, and chitosan-TPP nanogel particles were found to be spherical and homogenously dispersed. IL-2 loaded chitosan-TPP nanogel was found suitable for improving wound healing because it decreased the MDA levels and increased the GSH levels wound tissues comparing to control group.

Evaluation of non-radioactive endpoints of ex vivo local lymph node assay-BrdU to investigate select contact sensitizers.

The present study sought to verify the utility of the non-radioactive endpoints LLNA BrdU (5-bromo-2'-deoxyuridine) ex vivo incorporation and cytokine release using auricular lymph node cells isolated from BALB/c mice topically treated with a strong (formaldehyde or p-phenylene-diamine [PPD]), moderate sensitizer (cinnamal), or weak sensitizer (eugenol). Stimulation index (SI) and EC3 values were calculated for each agent. Based on the results of ex vivo LLNA-BrdU assays, EC3 values were calculated to be 0.29, 0.09, 1.91, and 16.60% for formaldehyde, PPD, cinnamal, and eugenol, respectively. These results were in good agreement with data from previous standard radioactive LLNA. Cytokine analyses indicated T(H)1 and T(H)2 cytokine involvement in the regulation of murine contact allergy and these could be utilized as endpoints in assessments of contact allergy in mice. In conclusion, the current study provided evidence that the non-radioactive endpoint LLNA BrdU ex vivo incorporation could be of use as a viable alternative approach to assess the skin sensitization potential of test compound with respect to improving animal welfare. This is of particular importance in the case of any laboratory where it might be difficult to handle and/or readily employ radioisotopes. Further studies will be required to confirm--across test agents--the reproducibility as well as the limits of utility of this new ex vivo BrdU method.

Diagnostic potential of serum direct markers and non-invasive fibrosis models in patients with chronic hepatitis B.

AIM: Liver biopsy is recommended in the majority of patients with chronic viral hepatitis for fibrosis evaluation. Because of the disadvantages of liver biopsy, many studies related to non-invasive biomarkers and scores have been performed. In this study, we aimed to assess the diagnostic value of serum direct markers and non-invasive fibrosis models to predict liver fibrosis in the treatment-naive chronic hepatitis B (CHB) patients and to compare their diagnostic performance. METHODS: This study included 58 patients with a diagnosis of CHB virus infection and 30 healthy controls. Hyaluronic acid, tissue inhibitor of matrix metalloproteinase 1 and amino-terminal propeptide of type III procollagen were measured by enzyme-linked immunosorbent assay; and the Original European Liver Fibrosis panel, the Enhanced Liver Fibrosis (ELF) panel, PP score, aspartate aminotransferase to platelet ratio index (APRI) and FIB-4 indexes were calculated using the formulas taken from previous publications. Fibrosis stage was determined using Ishak's scoring system. RESULTS: The fibrosis stages identified upon liver biopsy was F0 in 12 patients (20.7%), F1-2 in 36 (62.1%) and F3-5 in 10 (17.2%). The diagnostic value of all the non-invasive indices was low to detect mild fibrosis. We demonstrated that the diagnostic accuracy of HA is the best for predicting fibrosis of F3 or more (area under the receiver-operator curve, 0.902). In our study, the results from a combination of tests showed that ELF and APRI had the highest diagnostic value sensitivity of 90%, specificity of 100%, positive predictive value of 100% and negative predictive value of 96.4% for detection of fibrosis of F3 or more. CONCLUSION: In CHB patients, combination of ELF and APRI has a better diagnostic value in predicting fibrosis of F3 or more.

Matrix metalloproteinase-7 and matrix metalloproteinase-9 in pediatric multiple sclerosis.

Matrix metalloproteinases and their tissue inhibitors play a key role in the pathogenesis of adult-onset multiple sclerosis, and were suggested as biomarkers of response to interferon-ß, an established treatment in multiple sclerosis. However, data regarding pediatric population are scarce. We determined serum levels of matrix metalloproteinase-7, matrix metalloproteinase-9, and tissue inhibitor of matrix metalloproteinase-1 in children, and evaluated effects of interferon-ß therapy on these measures. Serum samples from 14 children with relapsing, remitting multiple sclerosis at baseline and at month 12, and from 15 controls, were collected. Interferon-ß treatment was initiated in eight patients. Mean serum matrix metalloproteinase-9 levels and matrix metalloproteinase-9/tissue inhibitor of matrix metalloproteinase-1 ratio were higher in patients compared with controls, and were reduced significantly in treated patients at month 12, but did not change in untreated patients. Mean matrix metalloproteinase-7 levels were lower in patients compared with controls, and increased significantly in the treated group, but did not change significantly in the untreated group. In pediatric multiple sclerosis, a shift in matrix metalloproteinase-9/tissue inhibitor of matrix metalloproteinase-1 balance toward proteolytic activity is evident, and interferon-ß therapy demonstrates a beneficial effect on this disturbed balance.

Is neopterin a diagnostic marker of acute appendicitis?

BACKGROUND: The diagnosis of acute appendicitis, even for experienced surgeons, can sometimes be complex. A delay in diagnosis increases the complication rate. This experimental study aimed to investigate the suitability and significance of neopterin as a marker for acute appendicitis. METHODS: The levels of neopterin were measured using an acute appendicitis animal model in 35 New Zealand male rabbits. They were divided into 5 groups as Group 1= control; Group 2= sham; and Groups 3 (12-hour); 4 (24-hour); and 5 (48-hour) (based on the elapsed time period before their appendectomies). The neopterin levels of each group were measured by neopterin enzyme immunoassay kit in blood samples (taken before the appendectomies in Groups 3, 4 and 5). RESULTS: For the diagnosis of acute appendicitis, the optimal cut-off point was 34.475 nmol/L. The probability of acute appendicitis was found to be 4.667 times higher when the neopterin level was greater than 34.475 nmol/L. CONCLUSION: This study was an experimental animal study; however, it provides valuable clues useful in clinical assessment. Neopterin seems to have great potential as a new diagnostic marker for the diagnosis of acute appendicitis.

Evaluation of auricular lymph node cell lymphocyte proliferation and cytokine production as non-radioactive endpoints during murine contact allergy.

The murine local lymph node assay (LLNA) has been developed as a test method to assess allergic contact dermatitis. In spite of the validity of the LLNA, attention was drawn to the two disadvantages: use of radioactivity for in vivo measurement of lymph node cell proliferation ([(3)H]-thymidine labeling) and the possibility of false positive results caused by non-specific cell activation as a result of inflammatory processes in the skin (irritation). We aimed to investigate the following non-radioactive endpoints of LLNA: 5-bromo-2'-deoxyuridine (BrdU) incorporation ex vivo and in vivo, in vivo and ex vivo cytokine production with or without phytohemagglutinin (PHA) stimulation. Here, 8-12-week-old female BALB/c mice were treated topically with the strong sensitizer 2,4-dinitrochlorobenzene (DNCB) in acetone:olive oil (AOO, 4:1 [v/v]) at levels of 0.025, 0.05, 0.01, or 0.25% (w/v). Ear thickness was also measured to determine the differentiation index (DI) indicating the proportion of non-specific activation due to irritating properties of test compound. At the concentration of 0.05%, stimulation index (SI) value was found to be 3 for DNCB based on in vivo and ex vivo BrdU incorporation. The results of the in vivo and ex vivo non-radioactive LLNA assays were compatible both with each other and with previous radioactive LLNA data. Our results indicate that non-radioactive endpoints may be used as an alternative to the [(3)H]-thymidine LLNA. The levels of T(H)1 cytokines (IL-2 and IFNγ) and T(H)2 cytokines (IL-4 and IL-5) in lymph node cell cultures were significantly (P < 0.01) increased when DNCB was applied at the concentrations of 0.05 and 0.1%, respectively. As the DI was > 1, the applied concentrations of DNCB caused only allergic effect but not any irritant effect. This study reports that the use of these non-radioactive endpoints can assess allergic contact dermatitis caused by chemicals.

Community-based research: cost of the tests used for anti-HBc total seropositivity only and hepatitis B screening.

Our study aimed to determine anti-HBc total (IgG+IgM) seroprevalence in the adult population aged ≥ 15 and to compare the cost of testing for HBsAg and anti-HBs in only anti-HBc positive+ subpopulation to that in the whole population for HBV screening. The study involved a face-to-face survey and peripheral blood sampling from 452 adult subjects for HBV tests. HBV-DNA PCR was studied only in anti-HBc+ subjects. Of the 452 subjects anti-HBc total was positive in 192 (42.47%), of which: (a) 27 (14.06%) were HBsAg+, anti-HBs negative⁻, (b) 126 (65.62%) were HBsAg⁻, anti-HBs+, (c) 39 were HBsAg⁻, anti-HBs⁻. This last group (c) were tested for HBV-DNA PCR and six (15.38%) were positive. When we perform HBsAg and anti-HBs tests in all 452 subjects as in routine practice in blood banks, the cost is 3320 Euros. However, when all subjects are tested for anti-HBc total at first and then only anti-HBc total+ ones are tested for HBsAg and anti-HBs, the cost is 2929 Euros. The cost difference between the two methods is 391 Euros for 452 subjects. Accordingly, our HBV screening algorithm brings a financial saving of 11.78% and helps to identify the isolated anti-HBc total+ subjects who carry potential risk for spreading HBV.

Effects of scaling and root planing and subantimicrobial dose doxycycline on gingival crevicular fluid levels of matrix metalloproteinase-8, -13 and serum levels of HsCRP in patients with chronic periodontitis.

BACKGROUND: This study evaluates the efficacy of subantimicrobial dose doxycycline (SDD) in conjunction with scaling and root planing (SRP) on gingival crevicular fluid (GCF) levels of matrix metalloproteinase (MMP)-8 and -13 and on serum levels of high-sensitivity C-reactive protein (HsCRP) in patients with chronic periodontitis (CP). METHODS: A total of 41 patients with CP and 17 healthy individuals were included in this randomized controlled trial. CP patients were randomly distributed into two groups. Study groups were established as Group I with SRP+placebo, Group II with SRP+SDD, and Group III as control. All CP patients received two regimens of SRP and Group II patients also received SDD for 6 weeks. At baseline and 6 weeks, GCF and blood were collected and clinical indices were recorded. The HsCRP level was assayed in the plasma on a nephelometer. The GCF levels of MMPs were assayed by an enzyme-linked immunosorbent assay. RESULTS: Statistically significant differences in plaque index, gingival index (GI), probing depth (PD), GCF volumes, GCF MMP levels, and serum levels of HsCRP between pre-treatment and post-treatment were noted in both groups. Between groups there was a statistically significant decrease in PD, GI, and GCF levels of MMP-8 favoring the group receiving SDD adjunctive to SRP (P <0.05). CONCLUSION: In this study, greater improvement was detected for PD, GI, and GCF levels of MMP-8 when using SRP+SDD compared to SRP+placebo.