Mycobacterium avium subsp.paratuberculosis (MAP). To date, PTB diagnosis, based on serology, fecal culture, and real-time polymerase chain reaction, has identified animals in advanced stages of infection. To detect MAP infection in animals earlier, the interferon-gamma (IFN-γ) test may be applied. This assay detects cytokines produced by T-lymphocytes of infected subjects after stimulation with purified protein derivatives (PPDs), extracted from Mycobacterium bovis (MB) and from M. avium (MA). The study involved three bovine herds: one PTB-infected herd, one PTB-free herd, and one with an outbreak of bovine tuberculosis. The IFN-γ test was performed on 235 animals, using bovine PPD (PPDB), avian PPD (PPDA), and three experimental PPD Johnins (PPDJs) extracted from a synthetic liquid medium culture of MAP , to assess early MAP detection and avoid false reactions to MB. Furthermore, IFN-γ results were evaluated using 12 interpretative criteria (ICs), based on the differences and ratio between PPD optical density (OD) and IFN-γ basal OD values after lymphocytic stimulation. IC accuracy was expressed as area under the receiver operating characteristic curve. Through a longitudinal study, PPDJs proved to be specific and sensitive in the detection of MAP-infected animals. Among the evaluated ICs, six showed the best performance in terms of accuracy (p < 0.0001), highlighting PTB subclinical infections. In particular, the two best criteria reached sensitivity values of 100%  with a specificity of 91.8%  and sensitivity levels of 80.6%  with a specificity of 100% . Thus, the IFN-γ assay proved to be a useful diagnostic tool to identify early subclinical MAP-infected animals, in order to manage infected cattle or those exposed to MAP and to monitor younger calves within a herd. Furthermore, the IFN-γ test can be considered an additional test to avoid the introduction of MAP-infected animals, especially in herds where disease has already been eradicated and preservation of the health status is required to maintain the PTB certification level.Paratuberculosis (PTB), also known as Johne's disease, is a chronic proliferative enteritis of ruminants caused by  Mycobacterium avium subsp. paratuberculosis (MAP) is a slow-growing mycobacterium  due to Mycobacterium bovis (MB) (M. avium D4ER (PPDA), respectively. Johnin (PPDJ), similar to the other tuberculins, is a crude PPD obtained from a MAP culture in a synthetic liquid medium, inactivated by heat treatment, precipitated with trichloroacetic acid, and re-suspended in phenol and glycerin  response, characterized by the production of IFN-γ and other pro-inflammatory cytokines –41. Nevevis (MB) –67. Recevis (MB) . As repovis (MB) , 58, 60.glycerin , 68.In the present study, we used three different experimental PPDJs, which are produced in Italy at Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche “Togo Rosati” (IZSUM) and described by Corneli et al. .The commercial diagnostic ELISA tests available today that are used for bTB have not been validated by the manufacturer for the diagnosis of PTB , 58. TheThe aim of this longitudinal study was to evaluate the performance of three new experimental PPDJs and their potential application, in association with Italian PPDA and PPDB, in the IFN-γ test for the early detection of animals infected with MAP.For the production of the new Italian Johnin, 20 Italian MAP strains were genotyped by amplification of mini- and microsatellite loci at the Italian National Reference Center for PTB . Two fieAll samples were assessed as per the periodic tests required by the Italian National Health Programs –80 and dA total of 235 cattle from farms in central Italy were enrolled in the study and divided into three groups, as follows:The first group consisted of 87 dairy cattle from three bTB Officially Free (OF) herds, where clinical cases of PTB had been reported.The second group consisted of 61 beef cattle from a bTB OF herd without PTB cases, and the herd had tested negative for serological tests in the last 4 years.The third group included 87 beef cattle from a bTB-positive herd with an ongoing outbreak when the study was performed.Each animal from the bTB OF herds with previous PTB cases or without PTB was assessed in parallel to traditional PTB tests, as follows:® paratuberculosis Indirect”—IDVet Innovative Diagnostics, Montpellier, France) in accordance with the manufacturer's instructions;PTB ELISA test on serum  yielded a positive result.2. The obtained values were expressed in units of OD measured at 450 nm (OD 450 nm).Jugular blood samples were collected and delivered to the laboratory within 12 h at room temperature. The heparinized blood samples of each animal were dispensed in aliquots of 1 ml and stimulated, respectively, with phosphate-buffered saline , used as a nil control antigen, which represented the IFN-γ basal value in the single animal (PBS); 10 μg of Italian PPDB and 10 μg of Italian PPDA; 20 and 10 μg of the three experimental PPDJs , with two different dilutions 1:5 and 1:10; Pokeweed Mitogen  included at a final concentration of 1 μg/ml, as a positive control of lymphocyte viability. IFN-γ secretion was evaluated using the Bovigam IFN-γ kit (Thermo Fisher Scientific™) in the plasma collected after 24 h of incubation at 37 ± 1°C in 5% CO* PBS > 0; 0.04 = MAP infection). From the sixth to ninth criteria, we considered the ratio between the PPD OD values obtained . For the 10th criterion, we compared the ratio between PPDs (PPDB/PPDA > PPDB/PPDJ = MAP infection); and finally, for the 11th and 12th criteria, we considered the difference between PPDA and PPDJs and two different cutoff values .For the PTB IFN-γ performance evaluation, a comparison among PPDB, PPDA, and PPDJ was carried out, applying differences or ratios among the PPD OD values obtained. For each criterion, different cutoffs were applied to interpret the results. In particular, 12 possible ICs were adopted in the first and second groups to assess the presence or absence of MAP (MAP reactive or MAP negative) and to evaluate the stage of MAP infection. In the third group, to verify the test performance and reliability in the presence of another mycobacterial infection, three of the best criteria, chosen among those evaluated, were adopted. The ICs, shown in For every criterion, a maximum threshold of the basal value (PBS ≤ 0.150 OD) was introduced to verify the eligibility of the sample. As reported in the literature , 86, thiThe sixth criterion is currently also adopted in the IZSUM for the official diagnosis of bTB.The performance of the PPDJs in the 12 IFN-γ test ICs was evaluated on the OD values obtained from a total of 235 cattle, including 87 cattle from PTB affected herds, 61 cattle from a bTB OF herd, without PTB cases in the last 4 years, and another group of 87 cattle from a bTB-positive herd.To establish the diagnostic accuracy and to compare the diagnostic efficiency of PPDJs, a receiver operating characteristic (ROC) curve analysis was performed. For each criterion, the Se, Sp, accuracy, area under the ROC curve (AUC), and Youden index were calculated. Differences in accuracy, Se, and Sp among the criteria were assessed using a binomial exact test.The association statistics, the AUC with its standard error, and a confidence interval (CI) for each model were calculated. Differences between the AUC for PPDJA, PPDJB, and PPDA were performed by ROCCONTRAST statements using the non-parametric approach of DeLong .For the purpose of the study, Se was defined as the proportion of samples with positive results from the expected true-positive animals, while Sp was defined as the proportion of samples with negative results to the expected true-negative animals.The Se of PPDJ  in the detection of MAP-infected subjects was calculated considering positive animals with a positive outcome in ELISA and/or qPCR and/or fecal culture. The Sp of PPDJ  was calculated considering negative animals with a negative outcome in ELISA, qPCR, and fecal culture from the herd PTB-free for at least 4 years.The PPDJ OD distribution was analyzed using histograms, and comparisons between dilutions and strains are shown in box plot graphs.Two types of analysis of variance were performed using Proc generalized linear models and SAS software v. 9.2 to evaluate the “dilution factor” (1:5 and 1:10) and “strain factor”  of the PPDJs, in particular if the PPDJ OD concentration values were different among the three strains and between the two dilutions.Animals belonging to the three groups underwent traditional PTB tests: ELISA PTB, qPCR, and MAP isolation from feces . Each suIn the first group, among the 87 cattle coming from bTB OF herds with previous PTB cases, 71 were positive for at least one of the traditional tests and 16 were negative to all the PTB tests. In particular, considering only the serological test, 68 subjects were positive, three were doubtful, and 16 were negative. Eighteen cattle were positive for real-time PCR from feces, and 28 were positive for MAP fecal culture. In the next 4 years, among the 16 subjects negative for the three PTB traditional tests at the first examination, five became positive during the follow-up . SpecifiIn the second group, among 61 cattle belonging to an OF bTB herd and without cases of PTB in the last 4 years, 100% of the animals were negative using conventional diagnostic tests.The third group consisted of 87 cattle from a herd in which bTB positivity to the skin test was registered and then confirmed by the isolation of MB. In the first sampling of the study, the bTB outbreak was still present and PPDA reactivity was found in the comparative skin test. For this reason, the IFN-γ test and ELISA PTB test were performed in support of the official bTB diagnosis to avoid false-positive bTB outcomes in eventually PTB-positive animals. The herd was monitored for another 2 years until the bTB-free status was regained and all animals were negative in the two ELISA tests performed annually.To evaluate the Se and Sp of the PPDJs using the different ICs, 128 animals were enrolled and followed up for 4 years. Among them, 67 from the first group were positive for at least one test for PTB, and 61 from the second group were always negative on the traditional tests for PTB. Out of 71 animals that tested positive for traditional PTB tests, four were considered outliers (PBS > 0.150 OD) and were therefore excluded from the performance evaluation.The amount of IFN-γ produced by the PTB-positive subjects, in response to stimulation with the various PPDs, expressed in OD values, is represented graphically in Regarding the assessment of PPDJ efficiency, analysis of variance showed no statistically significant differences between the mean OD 450 nm of the PPDJs and the dilution factor   or for tAs shown in Regarding the comparison of the diagnostic accuracy of PPDJs vs. PPDA, within the same criterion, statistically significant differences were observed in the second criterion . In addition, in the second criterion, the Sp of PPDJs was higher than that of PPDA, and the difference was statistically significant .p < 0.001 and p < 0.05, respectively. No difference was observed between AUC of PPDJA and PPDJB, since DeLong's test for two correlated ROC curves was statistically not significant (p > 0.05).Results of ROC analysis obtained with PPDA, PPDJA, and PPDJB according to the first three criteria are shown in As shown in In the third group, based on the data obtained from the application of the 12 criteria in the first and second groups on positive and negative PTB animals, respectively, the criteria with the best performance were used. In particular, in a herd with an ongoing bTB outbreak, the criteria that reported Sp values of 100%  were adopted with the aim of verifying the Sp of PPDJs.p < 0.0001) and PPDA .Out of 87 animals that were negative to ELISA PTB tests, seven subjects were considered outliers (PBS > 0.150 OD) and therefore excluded from the performance evaluation. As shown in Mycobacterium avium complex (MAC), mainly MAP  test and in the IFN-γ release assay, a reaction to PPDA can identify animals affected by PTB , 93–95. With the aim of producing new batches of PPDJ obtained from the field strains of MAPs common in our territory and to develop a more sensitive and specific IFN-γ test for the early diagnosis of MAP infection, three experimental PPDJs were produced at IZSUM, and different IFN-γ ICs were evaluated.From the first contact with mycobacteria, the immune response is characterized by a complex series of events aimed at controlling the infection before it can compromise homeostasis in the organism . In thisAs stated earlier, the “infected” animals that do not yet shed MAP and do not yet show clinical signs are the most difficult category to identify with ELISA, fecal culture, and qPCR, due to low antibody production and low or absent MAP shedding. In addition, the “subclinical infected” animals may contaminate the environment, but their detection by serological test and the direct MAP identification has lower probability of success, representing a significant challenge for the control and management of PTB . “AffectIn the present study, through a 4-year follow-up, it was possible to define the different stages of MAP infection in cattle of the first group from three PTB-affected herds, using new Italian Johnins in the IFN-γ assay. The obtained data represent the first assessment of the performance of experimental Italian PPDJs in the IFN-γ test and the first evidence of their ability to detect MAP-infected animals by adopting different ICs.The critical aspect of this study was the comparison between two different diagnostic approaches, one based on the IFN-γ test and the other based on traditional tests . The first approach is able to detect animals in the preliminary stages of MAP infection, while the second is useful when affected subjects are in the advanced stages of the disease or already have the clinical form of PTB. Therefore, the Se and Sp of the IFN-γ assay are related to the tests adopted to define the “positive animal.” These parameters are calculated on the basis of tests applied at the different stages of infection, in animal producing antibodies against MAP and/or in animal shedding MAP, while the IFN-γ test reveals infected animals that generally do not yet produce antibodies and do not yet shed MAP in their feces. This may have a negative effect on the performance of the IFN-γ test.Simultaneously to the performance evaluation of the new PPDJs, different criteria for the PTB IFN-γ test interpretation were developed and compared, particularly IC based on the difference between OD values and IC based on the OD ratio . Moreovep < 0.0001). In addition, both PPDJs with the first criterion achieved a higher accuracy related to values reached adopting IC from the third to sixth, and the difference was statistically significant for each criterion .The PPDJs achieved the best performance within the first six ICs, among the 12 applied ICs , with vap = 0.02), while PPDJB with the second criterion achieved the best Sp values , despite the accuracy being equal. As stated before, the Sp and Se are greatly affected by the tests used to detect the positive animal. On the basis of the six best ICs, in the first group, among 16 subjects with negative outcomes in the three PTB conventional tests, six were IFN-γ positive. The follow-up allowed monitoring of PTB progression, and five animals became PTB positive to traditional tests. In particular, two animals that reacted to both PPDA and PPDJs had PTB-positive bacterial culture 3 months later and also to the ELISA 10 months later. Among the three bovines reactive only to PPDJs, two animals became ELISA-positive 6 months later and a one bovine 18 months later. In the first step, these animals were considered “false positive” by statistical analysis, but the IFN-γ test with the six best ICs detected and unveiled MAP-infected cattle earlier than did the other traditional tests , and in terms of Sp, as in the case of the second IC . In fact, even though no statistically significant differences were observed between the first and second ICs, in terms of accuracy, PPDJB with the first criterion achieved better Se values . However, the analysis of the ROC curves of the PPDJA, PPDJB, and PPDA, according to the first three criteria (p > 0.05). Instead, it is important to highlight that AUC of PPDA was different from PPDJA and PPDJB and that the difference was statistically significant (p < 0.05).In terms of the mean IFN-γ production following stimulation with PPDJs and PPDA, there were no statistically significant differences  except icriteria , shows tThis result can be explained since MAP is part of the MAC; therefore, the remarkable similarities between PPD extracted from MAP and PPD extracted from MA do not permit the use of one against the other. However, in the criteria where both PPDJs and PPDA were used , the firAlthough valid criteria were highlighted in this study, in particular the first and the second, in our opinion, the main aspect is the adoption of different criteria in relation to the PTB status in each farm. In particular, it is advisable to use those criteria with a major Se, such as the first criterion, in herds with a high prevalence of PTB; on the contrary, apply more specific IC, such as the second criterion, in herds with low PTB prevalence, similar to the protocol described by Keck et al.  used in p < 0.0001). Always regarding the third criterion, PPDJA has shown higher Sp than PPDA, and the difference was statistically significant . Other authors  in the other groups. PPDJA achieved Sp values of 100% (CI 95%: 95.49–100%) when adopted in the third criterion, and the difference with other ICs was statistically significant (binomial exact test, In conclusion, the use of PPDJs and the interpretation of the IFN-γ test with the first or second criterion achieved high performance in the identification of MAP-infected cattle. Therefore, it can be assumed that the IFN-γ test could be a useful tool for identifying early subclinical MAP-infected animals, managing cattle infected or exposed to MAP, and monitoring younger calves within a herd.The IFN-γ test should be used for the early diagnosis of MAP infection, and it can be efficiently used to detect pre-maturely MAP-infected subjects within a herd. Considering that infected cattle may never shed MAP or show clinical signs of PTB, this would allow veterinarians and farmers to decide together about the future of infected animals. The future of the animal, that is, to keep or to cull, must be considered carefully based on PTB prevalence on a farm. In particular, in herds with high PTB prevalence, culling IFN-γ positive reactors could mean eliminating animals that are “controlling” the infection, and paradoxically these animals may be “resistant” to the disease, and as such, should be kept in the herd.On the contrary, in herds with low PTB prevalence or that are PTB-free, an animal that reacts positively to the IFN-γ test is definitely an animal that has been exposed to MAP or has contracted the infection; therefore, it has to be removed in order to maintain the low PTB or PTB-free status in the herd. Furthermore, the IFN-γ test can be considered as an additional test for animals that may be admitted to the herd, to avoid the introduction of MAP-infected subjects, especially in herds that have already eradicated the disease. Hence, the IFN-γ test will provide an additional diagnostic tool that farmers could adopt voluntarily to reach and preserve health status certification regarding PTB.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.PM: conceptualization. SC, ADi, CS, LC, PP, SCo, NV, ADo, and PM: methodology. NV: software. SC, ADi, and PM: validation. NV, LP, CS, MCi, LC, and PM: formal analysis. SC, ADi, CS, MCi, LC, MB, PP, SCo, and PM: investigation. SC, ADi, MB, ADo, and PM: resources. SC, ADi, NV, and PM: data curation. SC, ADi, MT, LP, and PM: writing original draft preparation. SC, ADi, MT, LP, MCa, and PM: writing review and editing. SC, NV, ADi, LP, and PM: visualization. SC, ADi, NV, MT, LP, MCa, ADo, and PM: supervision. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Objective: This study aimed to explore the association between base excess (BE) and the risk of 30-day mortality among patients with acute kidney injury (AKI) in the intensive care unit (ICU).Methods: This retrospective study included patients with AKI from the Medical Information Mart for Intensive Care (MIMIC)-IV database. We used a multivariate Cox proportional-hazards model to obtain the hazard ratio (HR) for the risk of 30-day mortality among patients with AKI. Furthermore, we utilized a Cox proportional-hazard model with restricted cubic splines (RCS) to explore the potential non-linear associations.Results: Among the 14,238 ICU patients with AKI, BE showed a U-shaped relationship with risk of 30-day mortality for patients with AKI, and higher or lower BE values could increase the risk. Compared with normal base excess (−3~3 mEq/L), patients in different groups  had different HRs for mortality: 1.57 , 1.26 , 0.97 , 1.53 , respectively. The RCS analyses also showed a U-shaped curve between BE and the 30-day mortality risk.Conclusion: Our results suggest that higher and lower BE in patients with AKI would increase the risk of 30-day mortality. BE measured at administration could be a critical prognostic indicator for ICU patients with AKI and provide guidance for clinicians. Acute kidney injury (AKI) is a severe complication in the intensive care unit (ICU), as it is associated with higher morbidity, mortality, and poorer outcomes. The incidence of AKI ranges from 2% in community settings to 20% among hospitalized patients and up to 60% in ICUs .Patients with AKI show an increased risk of mortality, chronic kidney disease (CKD) progression and cardiovascular complications . And theBase excess (BE) is defined as the amount of acid or alkali needed to adjust the value to the normal range , which iP < 0.0001). However, in this study, other confounders, such as age, sequential organ failure assessment (SOFA) score on admission, inotropes, and mechanical ventilation were significantly different between the two groups and were not adjusted.Smith  demonstrConsequently, the aim of this study was to explore the effect of baseline BE on mortality among patients with AKI.The data of this study were extracted from a large critical care database named Medical Information Mart for Intensive Care (MIMIC)-IV , 10, whiThis study included adult patients (≥18 years) with AKI defined according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria . The KDIThe variable of interest is baseline BE. Thus, we extracted the first measurement of BE at ICU admission as the baseline BE value. This was the main exposure factor in our study.2), and partial pressure of carbon dioxide (PCO2). AKI stages were defined by both SCr and the volume of Urine Output (UO) within the first 48 h after ICU admission according to KDIGO criteria , partial pressure of oxygen , and hospital LOS were regarded as secondary endpoints.In the present study, all variables had missing values of <20%. We used multiple imputation  to imputDescriptive statistics were used to present the differences between characteristics across the five groups of baseline BE values . Continuous variables were presented as mean ± standard deviation or median (IQR), and the differences between groups were identified using analysis of variance (ANOVA) or Kruskal–Wallis test. Categorical variables were presented as percentages, and comparisons between groups were made using the chi-square test or Fisher's exact-test.P-value < 0.05, in univariate analysis. To assess the robustness of the results, which could be affected by potential unmeasured confounders, we calculated the E-value. The E-value was defined as the minimum strength of association that an unmeasured confounder would have between the explaining variable and the outcome }.The Cox proportional hazards model was used to estimate the association between predefined groups according to baseline BE values and outcomes among critically ill patients with AKI. The model was adjusted by multiple covariates with a  outcome  and the In view of the hypothesis that the relationship between BE and risk of 30-day hospital mortality was non-linear, we further examined Cox models with restricted cubic splines (RCS) –16, withP-values were two-sided, and statistical significance was set at P < 0.05.All statistical analyses were performed using the R software (version 4.0.0). All reported A total of 18,855 patients fulfilled the definition of AKI. Of these 14,238 patients whose ICU time was more than 2 days had a BE value within 24 h after ICU admission. The study flow diagram is shown in 2, PCO2, and UO were lower. The proportion of patients using vasopressors and RRT was also higher. Patients with higher BE values tended to be female, older, and had lower lactate and PO2 values. These patients had higher values of pH, PCO2, SOFA, and SAPSII, tended to use fewer vasopressors and ventilation, and were more likely to have comorbidities such as congestive heart failure and chronic pulmonary disease.Baseline characteristics of the five BE groups are depicted in E-value was obtained as follows:According to the equation, E-value was relatively large; thus, we can consider the results to be robust to some extent.In our study, the P for non-linearity < 0.01). We can also conclude that the baseline BE value in the range of 0–5 mEq/L was a protective factor (HR <1). When the BE value was outside this range, it was a risk factor (HR > 1). The results of the multivariate analysis (P for non-linearity < 0.01).Furthermore, we used RCS to flexibly model and visualize the relationship between baseline BE values and 30-day all-cause mortality in the ICU. In the restricted quadratic spline regression model, baseline BE was taken as a continuous variable. In analysis  were simThe results of the secondary endpoints are presented in Subgroup analysis was based on the following strata: sex , AKI stage , SOFA score , and SAPS II score. We divided the patients into four subgroups according to SOFA score quartiles. We also divided the patients into two groups according to the median SAPS II score (median = 40). In almost all subgroups, when BE was in the range of −3~9 mEq/L, the patients had the lowest risk for mortality, and the patients in the fifth BE group (BE > 9 mEq/L) had the highest risk . SimilarBase excess was considered to be one of the most widely used markers in ICU, both to diagnose metabolic acidosis and to guide resuscitation or clinical intervention . In thisBE is convenient and intuitive for reflecting acid–base status in the ICU setting. Many studies have focused on base excess as one of the most essential indicators in ICU settings. For patients with trauma, the use of BE appeared to be better than vital signs or shock index for mortality prediction or rapid physiological assessment . A systeThe use of BE has also been extensively studied in burns. A prospective study including 42 major burn patients suggested that base deficit , as well as serum albumin level and hemoglobin concentration, were independent predictors of mortality among patients with burns . Binary The vital role of BE in prognosis and prediction has been demonstrated in many diseases. To determine the prognostic value of BE on admission among patients with acute heart failure (AHF), Hiroki Nakano et al.  concludeAs for AKI, the relationship between BE and all-cause mortality was more complex. The kidney plays a vital role in maintaining electrolyte homeostasis and acid–base balance. Acid–base disorder is not only a consequence, but also a contributor to the progression of kidney dysfunction.The U-shaped curve showed that lower BE (≤ -3 mEq/L), which indicated metabolic acidosis, would increase the risk of all-cause mortality in patients with AKI. This result was consistent with another study  which suThe results of subgroup analysis according to SOFA or SAPSII showed that the risk of mortality monotonically decreased when SOFA > 10, and the risk of mortality was also U-shaped when 4 < SOFA <7, 7 < SOFA <10, SAPS II ≥ 40, and SAPS <40. When the SOFA score was <4, there was no significant U-shaped relationship . Some stThis study had several limitations. First, BE remains a convenient and sensitive indicator for metabolic acid–base status, but it is not consistent with other markers such as lactate, bicarbonate, or anion gap . Thus, cIn addition, BE can be severely influenced by previous or concomitant administration of bicarbonate or lactate during resuscitation and in-hospital stay before ICU admission. The proportion of bicarbonate and lactate was shown in Furthermore, AKI can influence the acid–base imbalance; in turn, acid–base status can also be the result of therapies for deteriorating renal function, such as fluid resuscitation, use of diuretics, and RRT. Thus, for prerenal AKI, BE was appropriate for measuring the acid–base status. In contrast, BE had minimal utility for intrarenal or post-postrenal AKI. For example, when patients are on RRT in the ICU setting, BE only reflects the concentration of bicarbonate buffer and the duration of treatment. We considered that the low before ICU administration rate of bicarbonate and lactate might not affect the primary results substantially.Finally, we considered the first measurement of BE at administration, regardless of the influence of dynamic variation in BE. In the follow-up study, we built a joint model for longitudinal and time-to-event data , 31 to cBE could be an independent risk factor for all-cause death in patients with AKI in the ICU setting. Abnormal BE may be a risk factor for these patients. We also found a U-shaped association between baseline BE and all-cause mortality in patients with AKI. Regardless of whether BE is lower (BE ≤ −3 mEq/L) or higher (BE ≥ 9 mEq/L), it can increase the risk of 30-day ICU mortality in patients with AKI. Thus, BE measured at administration could be a good indicator of the severity of illness and provide guidance for clinicians.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.YC, YQ, YoZ, and CW designed the study and wrote the manuscript. YT, BT, WG, and XC performed the statistical analysis. RQ, DL, YaZ, SW, and RZ collected the study data. All authors participated in writing and revising the manuscript and read and approved the final manuscript.This work was supported by Three-Year Action Plan for Strengthening Public Health System in Shanghai (2020-2022) Subject Chief Scientist (No.GWV-10.2-XD05); Military logistics scientific research project (No. AWS14R013-1); Military Key Disciplines Construction Project-03; Natural Science Foundation of Shanghai (No.19ZR1469800); The National Natural Science Foundation of China (No. 82003558).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. 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Multiple sclerosis (MS) is an inflammatory disease damaging the myelin sheath in the central and peripheral nervous system in the brain and spinal cord. Optic Neuritis (ON) is one of the most prevalent ocular demonstrations of MS. The current diagnosis protocol for MS is MRI, but newer modalities like Optical Coherence Tomography (OCT) are already of interest in early detection and progression analysis. OCT reveals the symptoms of MS in the Central Nervous System (CNS) through cross-sectional images from neural retinal layers. Previous works on OCT were mostly focused on the thickness of retinal layers; however, texture features seem also to have information in this regard. In this research, we introduce a new pipeline that constructs layer-stacked (LS) images containing data from each specific layer. A variety of texture features are then extracted from LS images to differentiate between healthy controls and ON/None-ON MS cases. Furthermore, the definition of texture extraction methods is tailored for this application. After performing a vast survey on available texture analysis methods, a treasury of powerful features is collected in this paper. As a primary work, this paper shows the ability of such features in the diagnosis of HC and MS (ON and None-ON) cases. Our findings show that the texture features are powerful to diagnose MS cases. Furthermore, adding information of conventional thickness values to texture features improves considerably the discrimination between most of the target groups including HC vs. MS, HC vs. MS-None-ON, and HC vs. MS-ON. Multiple sclerosis (MS) is an inflammatory disease damaging the myelin sheath in the central and peripheral nervous system in the brain and spinal cord. This disease causes the immune system to attack one or more proteins of the myelin structure and disrupts the ability of the nervous system to communicate and therefore brings about many physical signs and symptoms . Those sThe current diagnosis protocol for MS is Magnetic Resonance Imaging (MRI); however, researchers are already looking for substitute methods to overcome MRI limitations like high cost, late-stage diagnosis, and inaccurate signs due to aging rather than MS . The effOptical Coherence Tomography (OCT) is a noninvasive imaging modality to take cross-sectional images of biological tissues. Retinal OCT provides information on symptoms of many eye diseases such as macular degeneration, glaucoma, and diabetic retinopathy and helps ophthalmologists to diagnose and treat such diseases in a timely manner –7. ParisIn recent years, in the field of retinal OCT image processing, much attention has been paid to extracting and using texture features of layers while these types of features have not yet been used widely for MS diagnosis and there are few works addressing this issue. As an example, Varga et al. in 2015 had a study investigating the differences in texture descriptors and optical properties of retinal tissue layers in patients with MS and evaluated their usefulness in the detection of neurodegenerative changes using OCT image segmentation . The terHere is an overview of the literature investigating texture features in OCT images. In 2007, Baroni et al. investigated the possibility of discriminating retinal OCT image layers in texture processing using Grey-Level Cooccurrence Matrix (GLCM) feature extraction . In 2014The rest of this paper is as follows. The proposed method for texture extraction of retinal OCT layers is described in The data in this study is obtained from Spectralis Heidelberg HRA+OCT device in Faiz Hospital and Sadra Ophthalmology Center, Isfahan, Iran. The size of each B-scan is 496 × 480 pixels. For some subjects, data contains 19 B-scans, and for others, it includes 25 B-scans. OCT data includes 36 health control (HC) eyes and 39 patients suffering from MS (20 eyes suffering from MS with no history of ON (MS-None-ON) and 19 eyes suffering from MS with a history of ON (MS-ON)). HC and patient populations have matched gender and age approximately. A summary data flow diagram is presented in p value for distinguishing HC, MS-ON, and MS-None-ON population from retinal OCT layers around the fovea. Finally, in the last step, a classification between HC and abnormal population is performed. Each block of the proposed algorithm flow is elaborated below.The workflow of the proposed method is shown in The sample output of preprocessing block is shown in During texture calculation, boundary points in layer-stacked images have synthetic contrast which may fool the feature extraction method and lead to incorrect and outlier values. To solve this problem, an eliminating mask is developed to ignore pixels located on both sides of each individual layer.Feature extraction is then performed on masked layer-stacked images. The features used in our work are GLCM, Local Binary Pattern (LBP), Local Directional Pattern (LDP), Local Optimal Oriented Pattern (LOOP), and fractal dimension. Finally, discriminant features are fed into Support Vector Machine (SVM) and Linear Discriminant Analysis (LDA) classifiers for differentiating between HC and MS cases.Investigating texture features is an efficient way to characterize various properties, such as structure, orientation, roughness, smoothness, or regularity of an image. Extracting features from masked layer-stacked images, we apply two categories of texture features including original and modified features.Different texture analysis methods are utilized in this research and elaborated in the next subsections. A set of features are then extracted according to (1) Grey-Level Cooccurrence Matrix. GLCM describes the spatial relationship between each intensity tone by considering changes between grey levels i and j at a particular displacement distance d and at a particular angle θ [ angle θ . Here, w(2) Local Binary Pattern. LBP is a method for describing the texture characteristics introduced in 1990 [P is the number of neighboring points that are chosen, i.e., 8, ip is the intensity of the neighborhood points, and  ic is the intensity of the central point.  LBPP calculates the output of LBP for P neighboring points.(3) Local Directional Pattern. A more robust to noise modified version of LBP is LDP which computes directional components for each pixel with Kirsch kernels and provides a measure of the strength of intensity variation in those directions [xc, yc) with intensity ic, eight rotated versions of the Kirsch edge detector should be applied on neighboring pixels with intensities in n = 0, 1, ⋯, 7. Eight corresponding responses of the Kirsch masks are mn n = 0, 1, ⋯, 7. mk is the kth highest Kirsch activation, and all the neighboring pixels having Kirsch response higher than mk are assigned 1, and others 0. Then, the LDP value for the pixel  is given byrections . For eac(4) Local Oriented Optimization Pattern. LOOP offers a nonlinear combination of LBP and LDP that overcomes their individual problems while maintaining the strengths of each. Compared to LDP, LOOP assigns an exponential weight wn to each of neighboring pixels. wn is a digit between 0 and 7, according to the rank of the magnitude of mn among the 8 Kirsch mask outputs [xc, yc) is given by outputs . The val(5) Fractal Analysis. Images with self-similarity characteristics are called fractal. The box-counting analysis is an appropriate method of fractal dimension estimation for images with or without self-similarity [N is the number of boxes that cover the pattern, and r is the magnification or inverse value of the box size.milarity . We haveA higher slope means that the object is more fractal, i.e., reduction in the size of the box reveals more complexity. The lower slope means that the object is closer to the straight line, i.e., less fractal, and the amount of details does not increase rapidly with increasing magnification.Inserting zero values by masking layer-stacked images  of an entry in the cooccurrence matrix, and px+y(i) is the probability of cooccurrence matrix coordinates summing to x + y. HX and HY are the entropies of px and py. Finally, HXY, HXY1, and HXY2 are shown inFor GLCM, the first row and column of the output matrix (which represent unwanted zero pixels) are eliminated. The GLCM features listed in In LBP, LDP, and LOOP methods, the features in The last category of texture analysis methods to be considered is fractal analysis. Here, we remove the black background above the layer-stacked images before performing the masking step. The mean and standard deviation of the fractal dimensions for each image is then reported.t-test and Bonferroni correction. The Bonferroni correction is an adjustment made to p values when several dependent or independent statistical tests are being performed simultaneously on a single data set. To perform a Bonferroni correction, the critical p value (α) is divided by the number of comparisons being made.To handle the course of dimensionality problem caused by small number of available data compared to bunch of calculated features, more significant features are selected based on p value (p < 0.005) is divided by 4 and p < 0.001 is considered as a significant level for cut-off. After Bonferroni adjustment for multiple comparisons, features with p < 0.001 are selected as significant features. Then, two classification models, SVM and LDA, are utilized for differentiating between four possible groups including HC vs. MS, HC vs. MS-ON, HC vs. MS-None-ON, and MS-ON vs. MS-None-ON. A 10-fold cross-validation is used to evaluate accuracy, for each classification model.Here, considering that the majority of the features have been extracted from the GLCM matrix and this matrix has produced the features in four different angles, according to Bonferroni correction, the value of meaningful t-test is used to identify which features show significant differences between healthy and MS (ON and None-ON) cases . Frequencies of significant selected features for each retinal layer are also presented in To evaluate the statistical significance of the extracted features, the N) cases . The p vAccording to Tables t-test and Bonferroni correction15 common selected texture features based on Thickness featuresCombination of I and IIIn addition, to prepare a fair comparison with the previous studies, we also test the performance of the two classification models using thickness features as input. As abovementioned, utilizing texture features for our intended goal is totally novel and previous researches were only relying on thickness as discriminant features. Therefore, the thickness features are calculated as the average value of distance between two consecutive boundaries, which lead to 10 thickness values out of 11 retinal layer boundaries, and this thickness feature vector is fed also to each classifier. In summary, the following set of information are utilized as input of each two classifiers:As it can be found in Furthermore, the impressive point is that in case III and with the combination of texture and thickness features as input of the classifiers, the result improved considerably and also the performance of the LDA classifier is superior to the SVM performance in most of the conditions.There are no specific tests for MS detection. Instead, a diagnosis of MS often relies on ruling out other conditions that might produce similar signs and symptoms, known as a differential diagnosis. Blood tests, spinal tap (lumbar puncture), evoked potential tests, and MRI are the conventional MS diagnosis methods. The first MR images of MS were produced in the early 1980s . In mostMRI-based methods have been indeed the most successful techniques to estimate CNS damage up to the present, although it is becoming increasingly clear that due to the ability of direct visualization of retinal axons, OCT has become an extremely sensitive method for imaging neurodegeneration in MS patients. Studies show thickness reduction in retinal layers of MS patients with and without history of ON by OCT image analysis , 24–28. Indeed, texture analysis is a novel strategy for studying intrinsic changes in retinal layers during neurodegenerative diseases. MS, as one of the famous neurodegenerative disorders, is investigated in this research.After performing a vast survey on available texture analysis methods, a treasury of powerful features is collected in this paper. As a primary work, this paper shows the ability of such features in discrimination of HC and MS (ON and None-ON) cases. Even with simple classification methods, the texture features are powerful to diagnose MS cases (from HC ones) with accuracy of 85.3% and 72% with SVM and LDA classifiers, respectively.Another valuable point is that adding information of conventional thickness values to texture features improves the discrimination between most of the target groups including HC vs. MS, HC vs. MS-None-O, and HC vs. MS-ON. It should be noted that the results of the last group (MS-ON vs. MS-None-ON) are generally weaker than other groups due to the lack of significant discriminant texture features for this group.Furthermore, the findings show that some layers like 2, 3, and 4 carry more texture information useful in separation of HC from MS cases. Such finding can be a start point for further investigation in this area.


Nearly a year after the classification of the COVID-19 outbreak as a global pandemic, it is clear that different factors have contributed to an increase in psychological disorders, including public health measures that infringe on personal freedoms, growing financial losses, and conflicting messages. This study examined the evolution of psychosocial impacts with the progression of the pandemic in adult populations from different countries and continents, and identified, among a wide range of individual and country-level factors, which ones are contributing to this evolving psychological response. An online survey was conducted in May/June 2020 and in November 2020, among a sample of 17,833 adults  from eight countries/regions . Probable generalized anxiety disorder (GAD) and major depressive episode (MDE) were assessed. The independent role of potential factors was examined using multilevel logistic regression. Probable GAD or MDE was indicated by 30.1% and 32.5% of the respondents during phases 1 and 2, respectively (a 7.9% increase over time), with an important variation according to countries/regions (range from 22.3% in Switzerland to 38.8% in the Philippines). This proportion exceeded 50% among young adults (18–24 years old) in all countries except for Switzerland. Beyond young age, several factors negatively influenced mental health in times of pandemic; important factors were found, including weak sense of coherence (adjusted odds ratio aOR = 3.89), false beliefs (aOR = 2.33), and self-isolation/quarantine (aOR = 2.01). The world has entered a new era dominated by psychological suffering and rising demand for mental health interventions, along a continuum from health promotion to specialized healthcare. More than ever, we need to innovate and build interventions aimed at strengthening key protective factors, such as sense of coherence, in the fight against the adversity caused by the concurrent pandemic and infodemic. Since its first identification as a cluster of atypical pneumonias in Wuhan, China in December 2019 , researcAlthough signs of hope are appearing among the population, due to rapid advancements in the development, production and distribution of the COVID-19 vaccine, the psychological repercussions of COVID-19 continue to deepen as many countries face the second wave, and even a third one in some cases, of the pandemic. Extensive research on disaster mental health has established that emotional distress is ubiquitous in affected local communities; a finding certain to be echoed during the pandemic, but this time among virtually the entire world population, as no one is immune to its collateral damages ,6. ThrouMeasures implemented to control the spread of the COVID-19 virus vary greatly by countries and regions . CountriBeyond the stressors directly related to the pandemic, it is crucial to consider the infodemic as a critical factor contributing to the adverse outcomes of the COVID-19 pandemic. Not only can mis- and disinformation negatively impact an individual’s physical and mental health, they can ultimately affect countries’ abilities to stop the pandemic, as the effectiveness of public health measures is reduced due to poor compliance . As the Various factors play important roles in coping with a highly stressful situation such as the COVID-19 pandemic and the ensuing turmoil . Given tThe pandemic has had, and will continue to have, profound psychological effects around the world. It is essential to understand how the adverse mental health outcomes are progressing with the perpetuation of the health crisis, and how they are influenced by the infodemic and other challenges arising in the context of the pandemic. Multilevel factors that positively or negatively contribute to the psychological response of the population must be better understood, to put in place appropriate interventions. Numerous studies have explored these factors in conjunction with prospective changes in mental health, while others demonstrated the association between COVID-19 and mental health along with their influencing factors. However, additional research should be carried out to examine factors that affect the mental health of the population over time, to inform the development of sound mitigation strategies. This study therefore aims to (1) examine the evolution in anxiety and depression with the progression of the pandemic in adult populations from different countries and continents and (2) identify, among a wide range of individual and country-level factors, which ones are positively or negatively contributing to this evolving psychological response.This study is the second phase of an interdisciplinary and international survey (conducted in eight countries from four continents) on the psychosocial impacts of the COVID-19 pandemic among adults and its associated risk and protective factors. This is part of a larger multidisciplinary research project funded by the Canadian Institutes of Health Research. The study was conducted in accordance with the Declaration of Helsinki, was reviewed and approved by the Research Ethics Board of the CIUSSS de l’Estrie—CHUS (HEC ref: 2020-3674). Further details concerning the goals, objectives and methods of this broad research project can be found elsewhere ,22. The To ensure continuity between the two phases of the project, the same polling firms were responsible for the recruitment of participants and coordination of the data collection. Great attention was paid to the recruitment and sampling methods, which were consistent between participating countries (or regions) and between the two phases of data collection, in order to make the data comparable. Eligible participants consisted of adults (≥ 18 years) residing in the eight participating countries or regions. The participants were randomly selected from online panels, curated by the polling firms using various sources. Substantial efforts were made to maximize census representation. In addition to using targeted recruitment to ensure inclusion of hard-to-reach groups, two strategies ensured the optimal representativeness of the sample: the use of software generating representative samples of the population  and weighting of data based on age, sex and region in each participating country or region. For additional information concerning the recruitment procedure, the published article on the first phase of the study may be consulted . The finAn online questionnaire was used as the data collection instrument. The questionnaire is centred on the concepts of the Knowledge–Attitude–Practice (KAP) model , allowinProbable generalized anxiety (GAD) and major depressive episodes (MDE) were conserved as the two main assessed psychological outcomes. To evaluate these outcomes, the online questionnaire contained the GAD-7 and the Patient Health Questionnaire-9 (PHQ-9) scales, based on the diagnostic criteria for GAD and MDE described in DSM-IV. Although these scales are designed to be used in clinical settings by professionals, their use is also appropriate in population-based studies and they are often used as such. For each item on the respective scales, participants were asked to state their frequency according to four options . While the GAD-7 score ranges between 0–21 and the PHQ-9 score ranges from 0–27, the cut-off score of 10 or above for both scales identifies moderate to severe symptoms of GAD or MDE ,25. ThesIn the first phase of the study, factors that were assessed in the online survey were primarily factors that positively or negatively influenced the psychological response to the pandemic at an individual level. They were classified into four distinct categories, that is demographic characteristics, factors related to the pandemic, factors related to the infodemic, and individual psychological resources. These same factors were also explored in the second phase of the study  and household composition . Being an essential worker was also assessed; however, this characteristic was further broken down to distinguish healthcare and social service workers from other essential workers . Similar to the previous phase, education level was not included in the international analyses. A barrier encountered in the previous analyses was the varying education systems among participating countries/regions, making it difficult to assess degree equivalency. To counter this, the data collected was converted to corresponding International Standard Classification of Education . However2 test was used to compare these participant characteristics across countries, by measurement wave. Treating countries as fixed effects, binomial regression models (with identity link function) were used to estimate rates of GAD or MDE indication by sex, age groups, country, measurement waves and two-factor interactions. As participants were nested within countries, and individual-level and country-level variables were available for analysis, a multilevel mixed-effects logistic regression model was considered and compared against the fixed effects binomial regression model, using the Bayesian Information Criterion (BIC). The BIC is used to select between these competing models; it rewards for goodness-of-fit to the data but penalizes for model complexity, with the preferred model balancing these opposing demands and yielding the lowest BIC statistic [The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) guidelines were used to inform the reporting of analyses . Initialtatistic . The multatistic , all maiThe final sample totaled 17,833 adults; 8806 from measurement wave 1 (June 2020) and 9027 from wave 2 (November 2020). To ensure the representativeness of the sample, the data were weighted according to sex, age and region of residence. When observing the sample as a whole, 51.8% of the participants were females, 49.2% were aged from 18–44 years old, 30.2% lived in households with children and 26.0% stated that they were essential workers, of whom 36.5% were healthcare or social service workers. 2 test, significant differences were observed among countries for all characteristics (p < 0.001) with the exception of sex . When comparing these values to the national statistics of each country, the study samples appeared broadly representative. In addition, the sample characteristics resembled closely the sample previously obtained during the first phase of the study, which allowed a more accurate comparison between the two waves.When analyzing the data distribution at each measurement wave for sex, age, household composition and essential worker status using the corrected weighted Pearson χ2 test p < 0.001). Similarly, probable MDE was indicated by 25.5% and 27.8% of participants in June and November, showing a significant increase (corrected weighted Pearson χ2 test p = 0.002). For measurement wave 1 (June 2020), 1427.7 (16.2%) participants were indicated for both probable GAD and MDE and 2660.6 (30.2%) were indicated for either probable GAD or MDE; whereas for the second measurement wave, 1700.8 (18.8%) participants were indicated for both probable GAD and MDE and 2937.3 (32.5%) were indicated for either. More information concerning the indication of GAD/MDE can be found in p < 0.001).Overall, the data demonstrated an increase in negative psychological outcomes between the first and second measurement waves. Probable GAD was indicated by 21.0% and 23.6% of participants in June and November, respectively, an increase that was significant (corrected weighted Pearson χp < 0.001) whereas the interactions between measurement wave × sex (p = 0.62), measurement wave × country (p = 0.30), and age × sex (p = 0.20) were not. This implies that the pattern of indications over age significantly changed between the measurement waves. Repeating the binomial regression model analysis, keeping the significant measurement wave × age interaction term, revealed that indications were significantly different between countries (p < 0.001), sex (p < 0.001), age (p < 0.001), measurement waves (p < 0.001), and measurement wave × age (p < 0.001). When modelling weighted probable GAD or MDE indications, adjusting for sex, age, country, and measurement wave, together with considered two-factor interaction terms, the interaction between measurement wave × age was significant . Thus, pursuant analyses treated participants as being nested within countries, which were modelled as random intercepts. In this multilevel mixed-effects model, females had odds of probable GAD or MDE indication 1.24  compared to that of males, and to those aged ≥ 65 years; participants aged 18–24 years had odds of probable GAD or MDE indication 4.22  higher in June and 7.93  higher in November. The estimated intraclass correlation (ICC) among participants within the same country was 0.020 . In other words, only 2% of the variance in psychological outcomes under study were explained by country-level factors, suggesting that most of the variation lies between people. p < 0.05). Conversely, variables measuring essential worker status, self-isolation/quarantine, threat perceived for country and/or world, being a victim of stigma, level of information about COVID-19, trust in authorities score, and social networks used as a regular source of information had significant associations with probable GAD or MDE indication but no such interaction with measurement wave.The considered sociodemographic and potential stressor variables were next individually added to this model, together with their interaction over measurement wave see . Variablp < 0.001) and the GINI index (p = 0.03) were significantly related to probable GAD or MDE indication.Next, country-level predictors were considered. p = 0.14), and all considered main effects also remained significant except for the country-level GINI index (p = 0.56) and the individual-level variable friend/family/coworkers as a regular source of information (p = 0.32), although the interaction term for this latter variable was significant (p = 0.04). Notably, in this analysis, those aged 18–24 years had high-adjusted odds for probable GAD or MDE indication  compared to their older aged ≥ 65 years, and this was worse in November . Additionally, a weak SOC yielded a high-adjusted odd for probable GAD or MDE indication at measurement wave 1 , which significantly increased in November   including all countries omitting the false beliefs score variable; (2) including all variables and omitting Hong Kong participants. 008) see .p = 0.25), threat perceived for oneself and/or family (p = 0.09), false beliefs score (p = 0.93), and friend/family/coworkers as a regular source of information (p = 0.22), and all considered main effects also remained significant except for the country-level GINI index (p = 0.18) and the individual-level variable friend/family/coworkers as a regular source of information (p = 0.75). Again, those aged 18–24 years and weak SOC carried a relatively high odds of probable GAD or MDE indication compared to their peers—a burden that significantly worsened in November.Undertaking analysis (2), generally similar patterns emerged. All included interactions with measurement wave remained significant except for household composition  all over the world. Second, by using the exact same methodology , worsening of anxiety and depression levels have been documented, particularly in young adults, between Phase 1 (May–June 2020) and Phase 2 (November 2020). Third, beyond young age, a wide range of factors negatively influencing mental health in times of the pandemic were highlighted, important factors (based on the magnitude of the effect size) were found, including a weaker SOC, COVID-19-related false beliefs, and self-isolation or quarantine.Overall, we found a small but significant deterioration with the progression of the COVID-19 pandemic in the psychological health of the adult population from eight countries and four continents. A global increase of 7.9% in the indication of either GAD or MDE was indeed noted from June–November 2020, with almost a third of the participants (32.5%) exhibiting symptoms consistent with one of these mental disorders in November. As discussed in an earlier article, such prevalence is much greater than what was estimated in the prepandemic era .One key observation in the current study is of great importance and deserves full attention: in all countries but Switzerland, more than half of young adults reported symptoms consistent with GAD or MDE. This age group, which was already significantly affected by the pandemic in June 2020, showed deteriorating psychological health at a faster pace in the second half of 2020 than any other age group. There are many possible explanations for these disturbing results. Regardless of the pandemic, the transition from adolescence to adulthood has always been a stressful period filled with changes and adjustments . Since tInterestingly, the evolution of the epidemiological situation regarding the COVID-19 morbidity and mortality at the country-level does not seem to influence rates of probable anxiety or mood disorders. Indeed, despite being strongly affected by the second wave of COVID-19 during the time of the study, Switzerland and Belgium remain the two countries with the lowest indication for negative psychological outcomes. These countries seem to be less affected than New Zealand and Hong Kong, which reported very few new cases of the virus at the beginning of the month of November. Several studies have exposed the negative impacts of public health measures such as lockdown or stay-at-home recommendations on mental health regardless of the epidemiological situation in a country . The difWhen specifically considering the lower prevalence of GAD and MDE observed for Belgium and Switzerland, many potential factors may play a role in these findings. One aspect that must be considered is the timing between the waves (periods of confinement and deconfinement) in each respective country and the data collection periods. The first phase of data collection in June coincided with the first deconfinement in Belgium and the second phase in November fell just at the beginning of the second confinement. Another study done by the University of Louvain in Belgium revealed high levels of psychological distress for the month of March (the start of the confinement) and April (the peak of the first wave) . AnotherFurthermore, the total population size of a country was found to act as independent predictor of either probable GAD or MDE. At first glance, it could be hypothesized that a larger size country could be affected negatively by both complex crisis management and communication strategies, resulting in increased negative mental health outcomes related to the pandemic. However, the relationship at stake might not be directly attributable to the population size, but rather their impact on trust, confidence and perception of proximity with authorities/elites . Confidence and trust in national and/or local state authorities are expected to be lower in larger populations, often facing more inequalities and economic stress ,38. LoweAs observed in the first phase of the study, the SOC is still critical in protecting against adversity caused by the two concurrent crises . Recent work has identified courses of action shown to increase SOC and, in general, the adaptive capacities of individuals and communities during stressful situations such as the ongoing pandemic . InterveThis study has several limitations, the main one being its cross-sectional nature, precluding our capacity to infer a causal link between risk/protective factors and mental health outcomes. When interpreting the changes in the data over time, it is important to consider that this study uses a repeated-cross sectional design and not a longitudinal approach, making it more difficult to attribute the changes in negative psychological outcomes to the various variables studied. Additionally, despite tremendous efforts in achieving representativeness in our sample, some groups of the population may be underrepresented, including adults with lower literacy levels and those not having access to a computer or the Internet. When considering the possible distorting effects of the weighting of the data, the weights had minimal effects on our main estimates . Indeed, probable GAD or MDE was indicated by 32.2% and 32.5% of the respondents using the unweighted and the weighted data, respectively (a 0.9% difference), suggesting that weights did not led to distortions of effects. Although the use of a cut-off value in the PHQ-9 and GAD-7 scales facilitates the interpretation of the data relating to the GAD or MDE (probable disorder: yes or no), it can also lead to some limits. As the original data takes a continuous from, some details are lost when using a cut-off and the prevalence of some of the factors may be overestimated . AnotherThe world has entered into a new era dominated by psychological suffering and rising demand for mental health interventions along a continuum from health promotion to specialized healthcare. More than ever, there is a need to foster individual and collective resilience. Each community should attempt to build and share a common vision of its problems and vulnerabilities, but also of its resources and capacities, in order to jointly develop solutions tailored to the local context and to thrive in these uncertain times. As observed, poor mental health outcomes associated with lockdown and other collateral damages of the pandemic (and the infodemic) could be better mitigated with ongoing assessment of psychosocial impacts and associated stressors, informed decisions and thoughtful interventions at the individual and collective levels .There is still so much research needed in the practical and political fields. With regard to our research project, new questions were added to the measurement tool of the second phase (November 2020), including additional psychosocial outcomes  as well as another potential factors that may influence these outcomes in times of pandemic, that is personal political leaning . As a next step, our interdisciplinary team will explore how the pandemic may have influenced these very important public health issues and the contributing role of this “new” factor that has been rarely, if ever, assessed in times of pandemic.


Background: Data on the relationship between physical activity (PA) and hemorrhagic stroke (HS) are limited in Asian populations. This population-based longitudinal follow-up study therefore investigates whether PA is associated with a reduced risk of HS in Taiwan.Methods: A total of 58,857 subjects who had participated in the Keelung Community-based Integrated Screening Program between 2005 and 2012 were enrolled. Information about their PA, obtained using questionnaires, was used to categorize them into three groups according to their average weekly time engaged in it: (1) no PA, (2) low PA (<90 min weekly), and (3) high PA (90 min per week or more). Cox proportional hazard regression was used to evaluate the effect of PA on HS. Stratified analysis by sex and comorbidities  were conducted to evaluate their impact on the relationship between PA and HS.Results: Compared to the no-PA group, the adjusted hazard ratio of HS for the low-PA group was 0.74 , and for the high-PA group, 0.72 . The stratified analyses showed that, for the non-comorbidity strata, the beneficial effect of PA on reducing HS risk became stronger as PA increased. However, in the diabetes and hypertension strata, high PA did not appear to have any greater protective effect than low PA.Conclusions: Our findings suggested that even <90 min of PA per week might be beneficial to reduce HS risk. Such a low level of PA is likely to be more achievable and easier to maintain for the general population. Additionally, personalized recommendations based on pre-existing comorbidities may help optimize the beneficial effects of PA on HS prevention. Stroke is a leading cause of death and disability worldwide. Up to 80% of strokes can be prevented through the management of risk factors such as hypertension, diabetes mellitus (DM) , smokingThis study used data from the Keelung Community-based Integrated Screening program (KCIS), which was conducted by health-service centers in Keelung City, Taiwan . The impThe present study used KCIS data from 2005–2012, and linked them to Taiwan's national health insurance research database (NHIRD) and mortality registry for the same 8-year period plus the three following years, i.e., 2013–2015. The NHIRD and mortality-registry data were from the Health and Welfare Data Science Center database at National Taiwan University's Health Data Research Center. Taiwan's national health insurance program is single-payer, compulsory social insurance, and NHIRD is a large-scale healthcare database covering more than 98% of Taiwan's population. Therefore, by linking these databases, a large-scale representative sample of screening data and healthcare records can be collected for analysis. The data that support the findings of this study are available from the corresponding author upon reasonable request.The present study was approved by the National Taiwan University Hospital Research Ethics Committee. Before analyzing the data, all personal ID numbers in the database were encrypted as alphanumeric codes to protect personal information. The health data used in this study could only be accessed in a privacy-protected room within the Health Data Research Center. Because the data were in de-identified form and analyzed anonymously in a privacy-protected environment, the requirement for informed consent was waived.Are you currently in the habit of engaging in PA? (Answer options: 0. Never 1. Yes); and those who answered yes were also asked How many times do you engage in PA in a week? and How many minutes is your PA each time? Based on the answers to these two follow-up questions, each subject's weekly PA time was obtained by multiplying his/her self-reported number of weekly PA sessions by the minutes each one lasted.We carried out a longitudinal follow-up study to investigate the impact of PA on HS risk. The questionnaire asked each subject Based on the weekly PA time we calculated, the subjects were categorized into three groups: (1) a no-PA (NPA) group, comprising subjects who answered “Never” to our initial PA question; (2) a low PA (LPA) group, consisting of subjects whose weekly PA times were <90 min; and (3) a high PA (HPA) group, which included subjects whose weekly PA times were 90 min or more. We chose 90 min as the cut-off point between LPA and HPA because a prior population-based study in Taiwan showed that 90 min a week of PA reduced mortality from all causes . The recN = 61,466). We excluded subjects who had ever been diagnosed with a stroke  prior to their respective index dates. After excluding 1,811 subjects who had a history of stroke, 59,655 subjects were left.We defined the date of initial screening, i.e., questionnaire completion, as the index date. Subjects aged 20 or above at their index dates, provided that those index dates fell within 2005–12, were included  their first occurrence of HS, (2) their death, or (3) the end of 2015. A diagnosis of HS was determined by at least one inpatient discharge or two outpatient visits with a principal diagnostic code of HS (ICD-9-CM codes 430–432). Death dates and causes of death were obtained from the mortality registry.We examined the differences in demographic, lifestyle, and comorbidity variables across the three PA groups using chi-square tests and analysis of variance. The incidence rate was calculated as the number of HS events in the group divided by the total follow-up time of the group . We used the Cox proportional hazard regression analysis to estimate the effects of different PA levels on HS. Since the association between PA and HS may vary with sex and comorbidities, we conducted stratified analysis by sex and comorbidities to evaluate their impact on the association between PA and HS risks . An alphp < 0.0001). The average age of the HPA group (52.8 years) was higher than the NPA (44.0 years) and LPA (42.3 years) groups. Moreover, the prevalence of pre-existing comorbidities, such as diabetes mellitus, hypertension, hyperlipidemia, coronary heart disease, cancer, chronic obstructive pulmonary disease, and osteoarthritis, were higher in the HPA group than in the NPA and LPA groups.p = 0.0219), and the HPA group's, 0.72 .The three groups' respective numbers of HS events and adjusted hazard ratios (HR) are shown in In our analysis stratified by DM , both LPIn our analysis stratified by hypertension , for theFor the non-hyperlipidemia stratum in our analysis stratified by hyperlipidemia, the LPA group had a slightly lower risk of HS but lacking statistical significance , and being a member of the HPA group was associated with a lower risk of HS . In the hyperlipidemia stratum, on the other hand, both the LPA and HPA groups had a significantly reduced risk of HS .In sum, for the non-DM, non-hypertension, and non-hyperlipidemia strata, the protective effect of PA against HS became stronger as PA time increased. However, in the DM and hypertension strata, HPA was not associated with a lower risk of HS than LPA was.Although PA has been associated with a reduced risk of stroke , 15, theFor primary prevention of cardiovascular diseases, the World Health Organization recommends ≥150 min per week of moderate intensity or 75 min per week of vigorous-intensity of aerobic PA, or an equivalent mixture of the two . The AmeTo our knowledge, only a handful of studies have been published on the relationship between PA and HS risk in Asian populations. One study from Japan reported that moderate levels of PA seemed to be optimal for HS prevention, reducing the risk by ~30% . SimilarLikewise, few previous studies have assessed the impact of sex and pre-existing cardiovascular risk factors on the relationship between PA and HS risk. Our stratified analysis by sex  suggestsIn our analyses that were stratified by DM and by hypertension, PA seemed to have a greater protective effect against HS in the non-DM, non-hypertension strata. In addition, the HPA group experienced greater protective effects than the LPA group in those two strata. However, HPA was no better than LPA when it came to reducing HS risk in the DM and hypertension strata; i.e., there might be no advantage of HPA over LPA in individuals with these two conditions. But the cause of this apparent lack of benefit of more PA is unclear. It has previously been suggested that microangiopathy caused by DM or hypertension can lead to cerebral microbleeds , which mOur analysis stratified by hyperlipidemia, in contrast, showed that both LPA and HPA were associated with more HS risk reduction in the hyperlipidemia stratum than in the non-hyperlipidemia one . PreviouAccording to our analyses stratified by comorbidities , the HPA group had a higher magnitude of HS risk reduction than the LPA group in the non-comorbidity strata. Such findings imply that more PA per week should probably be recommended for relatively healthy persons without pre-existing cardiovascular risk factors as a means of HS prevention. In the comorbidity strata, however, the LPA group tended to experience a higher magnitude of HS risk reduction than the HPA group. Therefore, <90 min of PA per week might be a more appropriate approach to HS prevention for persons with pre-existing comorbidities such as hyperlipidemia. Accordingly, personalized recommendations based on the presence or absence of DM, hypertension, and hyperlipidemia may be helpful in optimizing the beneficial impact of PA on HS risk.Most previous studies conducted in the western countries have reported that participation in PA decreases with age , 25. On The key strength of the present study is its use of a representative, population-based sample with longitudinal follow-up. This enabled us to examine the long-term relationship between PA and the subsequent risk of HS. In addition, we included a variety of comorbid medical conditions in the adjustment for regression analysis. Nonetheless, several limitations should be acknowledged. First, this study used self-reported PA, and detailed information on exercise types and intensities was not available in the original KCIS questionnaires. Therefore, misclassification errors may be present. Second, diagnoses of HS and comorbidities in this study were determined using ICD codes from the NHIRD. This may raise concerns about diagnostic accuracy. However, as well as seeking maximize case ascertainment as described above, we should point out that the Bureau of NHI has formed various audit committees that randomly sample claim data and review the sampled patients' healthcare records so as to optimize diagnostic accuracy and quality of care . Third, Asian populations suffer HS more frequently than other populations. The present study has shown that even <90 min a week of PA might help to reduce HS risk in one such population. For most people, this level of PA is likely to be more achievable than the longer times recommended by the WHO and other organizations. Additionally, individualized recommendations regarding PA based on pre-existing comorbidities may help optimize the beneficial effects of PA on HS prevention. A modest amount of PA may be more favorable to lowering HS risk in patients with cardiovascular comorbidities  than a greater amount. Conversely, more intense and/or lengthy PA may be more conducive to reducing HS risk in people without such comorbidities. However, future studies are needed to confirm our findings.ntuhdrc@ntu.edu.tw.The data analyzed in this study is subject to the following licenses/restrictions: The datasets are managed by the Health and Welfare Data Science Center at National Taiwan University's Health Data Research Center. Requests to access these datasets should be directed to The studies involving human participants were reviewed and approved by National Taiwan University Hospital Research Ethics Committee. Written informed consent for participation was not required for this study in accordance with the national legislation and the institutional requirements.S-HF, L-SC, K-CY, and S-LP designed the research, wrote the manuscript, and conducted the research. S-HF, K-CY, and S-LP analyzed data. All authors have read and approved the final manuscript.This research was supported by a grant from the Ministry of Science and Technology, Executive Yuan, Republic of China (MOST 107-2314-B-002-051-MY2). However, the funder had no role in the study's design, data collection or analysis; the decision to publish it; or the preparation of the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


A solitary fibrous tumor of the chest (SFTC) is a subtype of solitary fibrous tumor (SFT) with a low incidence rate. The purpose of this study is to analyze the diagnosis and treatment of SFTC and the difference between benign and malignant solitary fibrous tumor of the pleura (SFTP) to improve the understanding of this rare disease.A retrospective analysis of fifty patients with SFTC (33 cases in the pleura and 17 in the lung) was performed. Clinical and imaging characteristics, pathological features, and treatment follow-up outcomes were analyzed.via plain computed tomography (CT) and enhanced CT was used for enhancement of the tumors. It was also found that 18 cases had necrosis, and 5 cases had calcification. The histopathology results showed that frequent nuclear division, obvious morphological variation, necrosis, and the high expression of Ki-67 cells are markers of malignant SFTC. There were significant differences in age, chest tightness, necrotic foci in CT, and expression of Ki-67 between the benign and malignant SFTP cases. All the patients who received treatment were given an excellent prognosis.The common symptoms of the 50 patients included a cough, expectoration, chest tightness, fever, and chest pain. Space occupying lesions were found A combination of enhanced CT, histopathology, and immunohistochemistry can be used for the accurate diagnosis of SFTC. Advanced age, chest tightness, necrotic foci in CT, and a high Ki-67 index were more likely to be malignant SFTP. Operation and radiofrequency ablation can provide favorable outcomes for both benign and malignant SFTC. These tumors originate from CD34al cells . The sital cells –7. SFTs al cells . AccuratChest computed tomography (CT), histopathology, and immunohistochemistry are the current methods used for diagnosis. However, there is still no uniform CT and histopathology phenomenon standard for distinguishing benign and malignant SFTC. For example, Cardillo et al.  identifiIn this study, we analyzed the clinical features, including the symptoms, signs, imaging, and pathology, of 50 cases of SFTC. Then, we explored the treatment and outcomes of all the patients, and finally, we compared the difference between benign and malignant SFTP.via CT and confirmed through histopathology. All tumors were risk-stratified by using the modified scheme proposed by Demicco et al.  and the lung (n=17). All SFTC were initially diagnosed o et al. . This stA diagnosis of SFTC depends on CT, histopathology, and immunohistochemistry. All the patients here underwent a plain CT scan, and 48 patients received an enhanced CT scan, and histopathology and immunohistochemistry were performed on all samples. For immunohistochemistry, the presence and level of anti-cluster of differentiation (CD)34 antibodies, vimentin, Bcl-2, signal transducer and activator of transcription 6 (STAT6), CD99, epithelial membrane antigen (EMA), smooth muscle actin (SMA), S-100, cytokeratin (CK), desmin, and Ki-67 were determined.Among the 33 patients with SFTP, 27 patients selected surgery as the initial treatment, 18 of them choosing open surgery and 9 of them opting for thoracoscope surgery. Two patients chose interventional treatment for their initial treatment. One of these 2 patients underwent CT-guided radiofrequency ablation of a mediastinal solitary fibroma as the initial treatment in the first month, the third month, and the seventh month after the diagnosis was confirmed. The other case underwent right diaphragmatic artery angiography and embolization, followed by radiofrequency ablation in the first month, second month, and sixth month, and thoracoscopic tumor resection in the fourteenth month. After surgery, 25 patients were selected for dynamic observation and follow-up, and one patient with a benign SFTP received deep hyperthermia (4 times) over a 4-month period, and one patient received docetaxel and carboplatin chemotherapy (4 times). The remaining four SFTP patients failed to undergo any treatment.All the 17 SFTL patients chose surgery, 7 of them selecting open surgery and 10 of them thoracoscopic surgery. None of them received adjuvant treatment after surgery.Death of any cause was selected as the primary end point, and recurrence of tumor was identified as the secondary end point. Nine cases were lost to follow-up, and the follow-up period for the other patients was 3–99 months, the last follow-up being on 25 September 2020. Telephone and outpatient follow-up were used, and the patients received routine follow-up, including chest CT and clinical examinations, every six months after treatment.SPSS 22.0 was used for statistical analysis. The measurement data with normal distribution were expressed by xˉ ± s, and the measurement data that did not conform to the normal distribution were represented by median (M)  . A Student’s t-test or rank sum test was employed for the comparison of measurement data between two groups, and the exact probability method was used to compare the two groups of classified data. A p-value < 0.05 indicated statistical significance.The baseline characteristics of the patients are listed in P=0.082) , while patients in the malignant group exhibited a higher incidence rate of chest tightness (p = 0.02).The diagnosis of SFTC depends on CT, histopathology, and immunohistochemistry. All the patients underwent a preoperative plain CT scan, and 48 of them also underwent a preoperative enhanced CT scan  the tumor cells were oval or short fusiform in shape and distributed unevenly in the matrix; (2) tumor cells mainly exhibited an unstructured random growth pattern; (3) the abnormality of the tumor cells was not significant; and (4) the nucleus was round or oval, and 0–4 mitotic were seen per high power field (HPF) , and one patient with malignant SFTC in the left pleura died 5 months after the diagnosis because of respiratory failure (without treatment). Both of the patients were more than 80 years old.Only one patient experienced a recurrence of the tumor. This patient, who had malignant SFTC in the left pleura, relapsed 79 months after surgery. He was given further surgery and adjuvant chemotherapy, and a favorable prognosis was obtained.In general, the prognosis for patients undergoing either open or thoracoscopic surgery was excellent.+ dendritic mesenchymal (stem) cells. Hence, CD34 is usually considered to be a diagnostic marker for SFTC  video-assisted thoracic surgery (VATS) is often used for visceral pleura tumors attached by a pedicle with a diameter of <4 cm; 2) auxiliary small incision thoracotomy is widely used for wide-based tumors 5–8 cm in size; and 3) conventional thoracotomy is utilized when the tumor is >10 cm. However, we used VATS for three patients with tumors >10 cm, and all of them obtained an excellent prognosis. Furthermore, in the postoperative follow-up to the end of the study, no metastasis or recurrence was found. It is worth mentioning that complete resection is an important factor affecting local recurrence and metastasis , and we In this study, we analyzed the diagnosis and treatment of SFT, but there are some limitations to our research. Firstly, the number of cases we investigated was small, and we did not compare the effectiveness and safety of open surgery and laparoscopic surgery. In our study, due to the small sample size at present, and the vast majority of patients received traditional surgical treatment, postoperative adjuvant chemotherapy and other systemic treatment were not carried out, and the number of patients with new treatment methods such as radiofrequency ablation and hyperthermia was less, so the comparison between traditional surgical treatment and new treatment was not carried out for the time being. Our future studies will address these two issues.In sum, our analysis of diagnostic methods and treatments for SFT concluded that middle age, chest tightness, necrotic CT manifestations, and a high Ki-67 index are more common in malignant SFTP, and these findings can provide direction for clinicians.The original contributions presented in the study are included in the article/The studies involving human participants were reviewed and approved by the Henan Institute of Respiratory Diseases, The First Affiliated Hospital of Zhengzhou University ethics committee. The patients/participants provided their written informed consent to participate in this study. Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.ZJ conceived the idea and conceptualized the study. LJ collected the data. ZZ analyzed the data. ZJ drafted the manuscript, then TB reviewed the manuscript. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.