Structure and biological activity in vitro of Flagellin and its mutants from Escherichia coli Nissle 1917.

Bacterial flagellin is a potent immunomodulatory agent. Previously, we successfully obtained flagellin from Escherichia coli Nissle 1917 (FliCEcN) and constructed two mutants with varying degrees of deletion in its highly variable regions (HVRs). We found that there was a difference in immune stimulation levels between the two mutants, with the mutant lacking the D2-D3 domain pair of FliCEcN having a better adjuvant effect. Therefore, this study further analyzed the structural characteristics of the aforementioned FliCEcN and its two mutants and measured their levels of Caco-2 cell stimulation to explore the impact of different domains in the HVRs of FliCEcN on its structure and immune efficacy. This study utilized AlphaFold2, SERS (Surface-enhanced Raman spectroscopy), and CD (circular dichroism) techniques to analyze the structural characteristics of FliCEcN and its mutants, FliCΔ174-506 and FliCΔ274-406, and tested their immune effects by stimulating Caco-2 cells in vitro. The results indicate that the D2 and D3 domains of FliCEcN have more complex interactions compared to the D1-D2 domain pair., and these domains also play a role in molecular docking with TLR5 (Toll-like receptor 5). Furthermore, FliCΔ274-406 has more missing side chain and characteristic amino acid peaks than FliCΔ174-506. The FliCEcN group was found to stimulate higher levels of IL-10 (interleukin 10) secretion, while the FliCΔ174-506 and FliCΔ274-406 groups had higher levels of IL-6 (interleukin 6) and TNF-α (tumor necrosis factor-α) secretion. In summary, the deletion of different domains in the HVRs of FliCEcN affects its structural characteristics, its interaction with TLR5, and the secretion of immune factors by Caco-2 cells.

Enhancing Rumen Fermentation and Bacteria Community in Sika Deer (Cervus nippon) through Varying Levels of Dragon Fruit Peel Polyphenolic Extract: An In Vitro Study.

The aim of this study is to investigate the effect of dragon fruit peel polyphenolic extract (DFPE) on gas production, rumen fermentation, and bacterial communities in sika deer using an in vitro technique. Three treatments with different DFPE levels (DFPE0, base diet; DFPE5, base diet + 5 mg/g DFPE; DFPE10, base diet + 10 mg/g DFPE, respectively; n = 6) were implemented. The phenolic composition of DFPE, gas production (GP), ammonia nitrogen (NH3-N), volatile fatty acid (VFA), and bacteria communities was evaluated after 24 h of incubation. The results showed that GP and NH3-N were reduced by DFPE supplementation. Total VFA, isovaleric acid, and valeric acid were increased (p < 0.05) by the addition of DFPE. No changes (p > 0.05) were observed in pH, acetic acid, propionic acid, isobutyric acid, butyric acid, and the ratio of acetic acid to propionic acid. Additionally, the alpha indexes, including Sobs, Shannon, and Ace, were increased by DFPE supplementation. Moreover, at the phylum level, DFPE supplementation increased (p = 0.01) Bacteroidota but reduced (p < 0.01) Firmicutes. At the genus level, compared to DFPE0, the DFPE10 had increased relative abundances of Rikenellaceae_RC9_gut_group (p < 0.01), norank_f_Muribaculaceae (p = 0.01), Lachnospiraceae_NK3A20_group (p < 0.01), Christensenellaceae_R-7_group (p < 0.01), and NK4A214_group (p < 0.01), decreased relative abundances of Streptococcus (p < 0.01), Oribacterium (p = 0.01), and Enterococcus (p < 0.01). Compared to DFPE0, DFPE5 had no change (p > 0.05) in all bacteria at the genus level except for decreased relative abundance of Enterococcus (p < 0.01). These results indicated that DFPE may be able to be used as a feed additive to enhance fermentation parameters and improve ruminal bacteria communities in Sika deer.

Effect of First-Line Serplulimab vs Placebo Added to Chemotherapy on Survival in Patients With Extensive-Stage Small Cell Lung Cancer: The ASTRUM-005 Randomized Clinical Trial.

Importance: Programmed cell death ligand 1 inhibitors combined with chemotherapy has changed the approach to first-line treatment in patients with extensive-stage small cell lung cancer (SCLC). It remained unknown whether adding a programmed cell death 1 (PD-1) inhibitor to chemotherapy provided similar or better benefits in patients with extensive-stage SCLC, which would add evidence on the efficacy of checkpoint inhibitors in the treatment of extensive-stage SCLC. Objective: To evaluate the efficacy and adverse event profile of the PD-1 inhibitor serplulimab plus chemotherapy compared with placebo plus chemotherapy as first-line treatment in patients with extensive-stage SCLC. Design, Setting, and Participants: This international, double-blind, phase 3 randomized clinical trial (ASTRUM-005) enrolled patients at 114 hospital sites in 6 countries between September 12, 2019, and April 27, 2021. Of 894 patients who were screened, 585 with extensive-stage SCLC who had not previously received systemic therapy were randomized. Patients were followed up through October 22, 2021. Interventions: Patients were randomized 2:1 to receive either 4.5 mg/kg of serplulimab (n = 389) or placebo (n = 196) intravenously every 3 weeks. All patients received intravenous carboplatin and etoposide every 3 weeks for up to 12 weeks. Main Outcomes and Measures: The primary outcome was overall survival (prespecified significance threshold at the interim analysis, 2-sided P < .012). There were 13 secondary outcomes, including progression-free survival and adverse events. Results: Among the 585 patients who were randomized (mean age, 61.1 [SD, 8.67] years; 104 [17.8%] women), 246 (42.1%) completed the trial and 465 (79.5%) discontinued study treatment. All patients received study treatment and were included in the primary analyses. As of the data cutoff (October 22, 2021) for this interim analysis, the median duration of follow-up was 12.3 months (range, 0.2-24.8 months). The median overall survival was significantly longer in the serplulimab group (15.4 months [95% CI, 13.3 months-not evaluable]) than in the placebo group (10.9 months [95% CI, 10.0-14.3 months]) (hazard ratio, 0.63 [95% CI, 0.49-0.82]; P < .001). The median progression-free survival (assessed by an independent radiology review committee) also was longer in the serplulimab group (5.7 months [95% CI, 5.5-6.9 months]) than in the placebo group (4.3 months [95% CI, 4.2-4.5 months]) (hazard ratio, 0.48 [95% CI, 0.38-0.59]). Treatment-related adverse events that were grade 3 or higher occurred in 129 patients (33.2%) in the serplulimab group and in 54 patients (27.6%) in the placebo group. Conclusions and Relevance: Among patients with previously untreated extensive-stage SCLC, serplulimab plus chemotherapy significantly improved overall survival compared with chemotherapy alone, supporting the use of serplulimab plus chemotherapy as the first-line treatment for this patient population. Trial Registration: ClinicalTrials.gov Identifier: NCT04063163.

Effects of Purple Corn Anthocyanin on Blood Biochemical Indexes, Ruminal Fluid Fermentation, and Rumen Microbiota in Goats.

The objective of this study was to observe the effects of anthocyanin from purple corn on blood biochemical indexes, ruminal fluid fermentation parameters, and the microbial population in goats. A total of 18 Qianbei Ma wether kids (body weight, 21.38 ± 1.61 kg; mean ± standard deviation) were randomly assigned to three groups using a completely randomized design. The group diets were: (1) control, basal diet, (2) treatment 1 (LA), basal diet with 0.5-g/d purple corn pigment (PCP), and (3) treatment 2 (HA), basal diet with 1-g/d PCP. The results showed that supplementation of PCP anthocyanin increased (P < 0.05) crude protein and gross energy digestibilities compared to the control. Compared to the control group, the inclusion of anthocyanin-rich PCP led to significantly increased (P < 0.05) plasma reduced glutathione and peroxidase concentrations. Goats receiving PCP had increased (P < 0.05) ruminal fluid acetic acid and a higher ratio of acetate to propionate, while the propionic acid, butyric acid, valeric acid, isobutyric acid, and isovaleric acid levels had decreased (P < 0.05). There was no significant difference (P > 0.05) in ruminal fluid alpha bacterial diversity among the three groups. At the phylum level, the feeding of PCP had significant effect (P < 0.05) on the abundances of Actinobacteriota, Proteobacteria, Elusimicrobiota, WPS-2, and Cyanobacteria. At the genus level, HA group had lower (P < 0.05) Prevotellaceae_NK3B31_group abundance compared to the other groups. In addition, significant differences (P < 0.05) were also observed for the ruminal fluid Eubacterium_nodatum_group, Amnipila, Ruminiclostridium, U29-B03, unclassified_c_Clostridia, Pyramidobacter, Anaeroplasma, UCG-004, Atopobium, norank_f_norank_o_Bradymonadales, Elusimicrobium, norank_f_norank_o_norank_c_norank_p_WPS-2, norank_f_Bacteroidales_UCG-001, and norank_f_norank_o_Gastranaerophilales among all groups. Taken together, the inclusion of anthocyanin-rich PCP increased the antioxidant potential, improved rumen volatile fatty acids, and induced a shift in the structure and relative abundance of ruminal microbiota in growing goats.

Parthenolide inhibits human lung cancer cell growth by modulating the IGF­1R/PI3K/Akt signaling pathway.

Lung cancer is the leading cause of cancer­associated mortality worldwide. Parthenolide (PTL), a natural product extracted from the plant Tanacetum parthenium, (a flowering plant in the daisy family, Asteraceae) has been reported to inhibit cancer cell growth, including that of human lung cancer. However, the underlying mechanisms by which PTL exerts its anticancer effect have remained to be fully elucidated. In the present study, Cell Counting Kit­8 and colony formation assays were used to assess the effect of PTL to inhibit cell proliferation, a wound­healing assay was performed to assess cell migration and western blot analysis and PCR were employed to reveal the molecular mechanisms by which PTL inhibits human lung carcinoma cell growth. The results indicated that PTL substantially inhibited cell proliferation and migration in two lung cancer cell lines A549 and H1299. Mechanistically, the phosphorylation of insulin­like growth factor 1 receptor (IGF­1R), Akt and forkhead box O3α (FoxO3α) was blocked by PTL. Furthermore, IGF­1­induced Akt [protein kinase B or (PKB)] and FoxO3α phosphorylation were also inhibited by PTL treatment. In addition, PTL significantly suppressed lung cancer growth in a subcutaneous xenograft mouse model. Taken together, the present in vivo and in vitro results indicate that PTL may suppress lung cancer growth through inhibiting IGF­1R­mediated PI3K/Akt/FoxO3α signaling, suggesting that PTL may be an attractive candidate for the treatment of lung cancer.

The TLR4/ERK/PD­L1 axis may contribute to NSCLC initiation.

Infection and inflammation serve an important role in tumor development. Toll­like receptor 4 (TLR4) is a pivotal component of the innate and adaptive immune response during infection and inflammation. Programmed­death ligand 1 (PD­L1) is hypothesized as an important factor for non­small cell lung cancer (NSCLC) immune escape. In the present study, the relationship between TLR4 and PD­L1, in addition to the associated molecular mechanism, were investigated. TLR4 and PD­L1 expression in lung cancer tissues were detected using immunohistochemistry, whilst overall patient survival was measured using the Kaplan­Meier method. The A549 cell line stimulated using lipopolysaccharide (LPS) was applied as the in vitro inflammatory NSCLC model. Associated factors were investigated using reverse transcription­quantitative PCR and western blotting. Lung cancer tissues exhibited increased PD­L1 and TLR4 levels compared with those of adjacent para­cancerous tissues, where there was a positive correlation between TLR4 and PD­L1 expression. In addition, increased expression of these two proteins was found to be linked with poorer prognoses. Following the stimulation of A549 cells with LPS, TLR4 and PD­L1 expression levels were revealed to be upregulated in a dose­dependent manner, where the ERK and PI3K/AKT signaling pathways were found to be activated. Interestingly, in the presence of inhibitors of these two pathways aforementioned, upregulation of PD­L1 expression was only inhibited by the MEK inhibitor PD98059, which can inhibit ERK activity. These data suggested that the ERK signaling pathway is necessary for the TLR4/PD­L1 axis. In conclusion, data from the present study suggest that TLR4 and PD­L1 expression can serve as important prognostic factors for NSCLC, where TLR4 activation may induce PD­L1 expression through the ERK signaling pathway.

MicroRNA-448 overexpression inhibits fibroblast proliferation and collagen synthesis and promotes cell apoptosis via targeting ABCC3 through the JNK signaling pathway.

Idiopathic pulmonary fibrosis (IPF) is a condition that results in the progressive deterioration of lung function with poor prognosis. The current study is aimed at exploring how microRNA-448 (miR-448) targeting ABCC3 affects fibroblast proliferation, apoptosis, and collagen synthesis of mice with IPF via the Jun N-terminal kinase (JNK) signaling pathway. Bioinformatics and dual-luciferase polymerase chain reaction were used to predict the relationship of miR-448 and ABCC3. The expression of miR-448 and ABCC3 was detected in IPF tissues. Using IPF mouse models, lung fibroblasts for the experiments were treated with miR-448 mimic, miR-448 inhibitor, si-ABCC3, or SP600125 (inhibitor of JNK) to evaluate the cell proliferation and apoptosis in response to miR-448. Reverse transcription quantitative polymerase chain reaction and western blot analysis were used to identify the expression of miR-448, ABCC3, and the activation of the JNK signaling pathway. ABCC3 was targeted and downregulated by miR-448 based on bioinformatics prediction and dual-luciferase reporter gene assay. Additionally, miR-448 was found to be highly expressed in IPF lung tissues with low expression levels of ABCC3. In response to the treatment of miR-448 mimic or si-ABCC3, lung fibroblasts exhibited decreased cell proliferation and increased apoptotic rates, whereas the miR-448 inhibitor reversed the conditions. Notably, we also found that miR-448 mimic inhibited the JNK signaling pathway. In conclusion, by using miR-448 to target and downregulate ABCC3 to block the JNK signaling pathway in mice with IPF, we found an increase in fibroblast apoptosis, inhibited cell proliferation, and decreased collagen synthesis of fibroblasts.

Transcriptional responses of LSm14A after infection of blue eggshell layers with Newcastle disease viruses.

LSm14A is a key innate immunity component of processing body (P-body) that mediates interferon-ß (IFN-ß) signaling by viral RNA. This is the first study to report chicken LSm14A (cLSm14A) cloning from blue eggshell layer, high tibia and frizzle chickens. The cLSm14A gene, encoding 461 amino acids, is highly homologous in the three types of chickens. The cLSm14A was extensively expressed in several tissues. The transcriptional level of cLSm14A was significantly increased in various stages of Newcastle disease virus (NDV) infection. In HEK293 cells, full length cLSm14A from blue eggshell layer was localized in the cytoplasm as dots. The results of this study indicated that cLSm14A is an important sensor that mediates innate immunity in chicken against NDV infections.

Detection of Lung Cancer by Analysis of Exhaled Gas Utilizing Extractive Electrospray Ionization-Mass Spectroscopy.

In this study, extractive electrospray ionization and mass spectrometry (EESI-MS) was used to evaluate whether volatile organic compounds (VOCs) in exhaled gases can serve as specific diagnostic markers of lung cancer. The patients with lung cancer were diagnosed by chest CT or chest X-ray exam and confirmed by histopathology and cytology. Patients with pulmonary infections were identified by imaging, pathological diagnosis, or improvement of symptoms after antiinflammatory treatment. The control group had no lung abnormalities in imaging. Exhaled gases were collected using a Tedlar sampling bag and were detected using electrospray ionization mass spectrometry. By combining statistical and analytical chemistry, characteristic volatile organic compounds were screened. The results show that butadiene, orotic acid, tetrahydrobiopterin, and N-phenylacetylglutamine in lung cancer patients are significantly different from those in the control and lung infection groups.

Cryptotanshinone inhibits cellular proliferation of human lung cancer cells through downregulation ofIGF-1R/PI3K/Akt signaling pathway.

Lung cancer is one of the most commonly diagnosed malignancies worldwide. Cryptotanshinone (CPT) is a diterpene quinone compound extracted from natural plants and has been reported to have anticancer effects in several cancers including human lung cancer. However, the mechanism by which CPT acts to prevent lung cancer cell growth is largely unknown. In the present study, by using MTT assay, colony formation assay, wound healing and western blotting assays, the effects of CPT on the cell proliferation and migration of human lung cancer cells and the potential cellular signaling mechanisms were investigated. The data demonstrated that CPT exhibited anti-proliferative effects against A549 and H1299 cells. In parallel, the migration of A549 cells was also markedly inhibited by CPT treatment. Further study indicated that CPT not only inhibited the basal phosphorylation level of insulin-like growth factor 1 receptor (IGF-1R) and RAC-alpha serine/threonine-protein kinase (Akt), but also blocked IGF-1 induced IGF-1R and Akt phosphorylation. Finally, it was demonstrated that pretreatment with CPT inhibited IGF-1 induced cell proliferation of A549 and H1299 cells. In conclusion, the results of the present study indicated that CPT inhibits the proliferation and migration of lung cancer cells via a mechanism that involves inhibiting the IGF-1R-mediated phosphoinositide 3-kinase/Akt signaling pathway. The data provides evidence that CPT could be developed as a potential therapeutic agent for the treatment of lung cancer.

Porcine reproductive and respiratory syndrome virus inhibition of interferon-ß transcription by IRF3-independent mechanisms in MARC-145 cells in early infection.

Interferon ß is an important antiviral molecule whose expression is triggered through recognition of viral components by pattern recognition receptors via a cascade of signaling molecules, while viruses could target these molecules to evade from innate immunity. IFN regulatory factor 3 (IRF3) plays a crucial role in innate immune responses. Here, we demonstrate that PRRSV infection did not induce IFN-ß gene transcription in MARC-145 cells, but inhibited poly (I:C) stimulated IFN-ß gene transcription instead. Such inhibition is time-dependent with the progression of PRRSV infection. We also show that the inhibition of IFN-ß transcription in the early stage of infection could not be due to inhibition of phosphorylation and nuclear translocation of IRF3, though significant decrease of p-IRF3 and its nuclear translocation in PRRSV-infected and poly (I:C) cells was observed later at 48 h post-infection. The different patterns of inhibition for IFN-ß transcription and IRF3 phosphorylation have important implications as to the mechanism(s) by which PRRSV suppresses the type I IFN signaling at early stage of infection. There could be mechanism(s) other than effecting on IRF3 or molecules upstream that require further investigation.

[Study of changes in extravascular lung water index of patients suffered from H7N9 avian influenza with acute respiratory distress syndrome].

OBJECTIVE: To analyze the characteristic of changes in extravascular lung water index (EVLWI) of H7N9 avian influenza patients who complicated with acute respiratory distress syndrome (ARDS), and to approach the relevance between EVLWI and severity, pulmonary oxygenation in patients with lung injury. METHODS: Four H7N9 avian influenza patients administered from April to June in 2013 in First Affiliated Hospital of Nanchang University were studied. The patients who suffered from severe ARDS were administered with low tide volume ventilation plus positive end-expiratory pressure (PEEP), namely protected ventilation strategy, with monitoring hemodynamic parameters and EVLWI through pulse-indicated continuous cardiac output (PiCCO) catheter. During ventilation, patients' parameters, such as PEEP, fraction of inspired oxygen (FiO2), arterial partial pressure of oxygen (PaO2), oxygenation index (PaO2/FiO2), cardiac index (CI), systemic vascular resistance index (SVRI), pulmonary vascular resistance index (PVRI), EVLWI, and central venous pressure (CVP) were collected. RESULTS: All 4 H7N9 avian influenza patients were complicated with ARDS, 2 patients were classified to severe ARDS and administered with comprehensive therapies, specially protected ventilation strategy; ventilation duration was 9 days and 30 days respectively, and PiCCO monitoring was 9 days and 21 days respectively. EVLWI of 2 patients on the 1st, 2nd, 3rd day was 10.0±3.2 ml/kg, 12.0±2.9 ml/kg, 14.0±4.2 ml/kg, and 24.0±6.7 ml/kg, 24.0±6.1 ml/kg, 23.0±5.8 ml/kg, respectively. As their conditions became better, patients' EVLWI decreased to 5.5±2.7 ml/kg and 7.0±3.0 ml/kg, respectively at weaning. PEEP and FiO2 of 2 patients were down-regulated, PaO2/FiO2 increased to 334±64 mm Hg and 142±53 mm Hg at weaning. However, no significant changes in CI, SVRI, PVRI and CVP in the 2 patients were observed. CONCLUSIONS: EVLWI increases when H7N9 avian influenza patients are complicated with severe ARDS. As the conditions get better, EVLWI returns to normal value gradually. There is relevance between the motive changes in EVLWI and severity of ARDS and pulmonary oxygenation.

Listeria monocytogenes aguA1, but not aguA2, encodes a functional agmatine deiminase: biochemical characterization of its catalytic properties and roles in acid tolerance.

Listeria monocytogenes is adaptable to low pH environments and therefore crosses the intestinal barrier to establish systemic infections. L. monocytogenes aguA1 and aguA2 encode putative agmatine deiminases (AgDIs) AguA1 and AguA2. Transcription of aguA1 and aguA2 was significantly induced at pH 5.0. Deletion of aguA1 significantly impaired its survival both in gastric fluid at pH 2.5 and in mouse stomach, whereas aguA2 deletion did not show significant defect of survival in gastric fluid. With agmatine as the sole substrate, AguA1 expressed in Escherichia coli was optimal at 25 °C and over a wide range of pH from 3.5 to 10.5. Recombinant AguA2 showed no deiminase activity. Site-directed mutagenesis revealed that all nine AguA1 mutants completely lost enzymatic activity. AguA2 acquired AgDI activity only when Cys-157 was mutated to glycine. AguA1 mutation at the same site, G157C, also inactivated the enzyme. Thus, we have discovered Gly-157 as a novel residue other than the known catalytic triad (Cys-His-Glu/Asp) in L. monocytogenes that is critical for enzyme activity. Of the two putative AgDIs, we conclude that only AguA1 functionally participates in the AgDI pathway and mediates acid tolerance in L. monocytogenes.

Functional characterization of porcine LSm14A in IFN-ß induction.

Human LSm14A has recently been found as a processing body-associated sensor of intracellular viral nucleic acids and triggers signaling for type I IFN expression. Here porcine LSm14A (pLSm14A) was cloned from the PK-15 cells. The pLSm14A ORF is 1392 bp in length, encoding 463 amino acids. The putative pLSm14A contains a Sm-like domain and two arginine-glycine-glycine (RGG) boxes. The pLSm14A has high identity at the amino acid level to those of bovine, human and mouse (93.5-97.4%) and is transcribed in different tissues of pigs. In HEK293 or Marc-145 cells, pLSm14A was localized in the cytosol as P-body-like dots. Expression of pLSm14A in HEK293 or Marc-145 cells enhanced activities of IFN-ß and NF-κB promoters, induced IFN-ß transcription, and potentiated poly(I:C)-induced IFN-ß promoter activation, indicating that pLSm14A is a potential signal molecule in the IFN-ß pathway of pigs. We also found that pLSm14A-induced IFN-ß promoter activity was down-regulated by porcine reproductive and respiratory syndrome virus infection in Marc-145 cells. Since pLSm14A is constitutively expressed in virtually all tissues, more research is needed to explore its role in initial phase of viral infections of pigs and its relationship with RIG-I in sensing PAMPs for type I IFN induction.

[Changes in the calcitonin content after inhalation injury in dogs].

OBJECTIVE: To investigate the changes in the serum content of immunoreactive calcitonin (iCT) after burns or inhalation injury, and to explore its diagnostic significance. METHODS: Twenty-four dogs were randomized into 4 groups, i. e. A (n = 6, with moderate degree inhalation injury) , B ( n = 6, with severe inhalation injury), C (n = 6, with most severe inhalation injury) and D (n = 6, with severe burns) groups. The serum content of iCT and blood gas analysis before and after injury were determined at different time points. The degree of inhalation injury was determined with fibrobronchoscopic examination at 6 post-inhalation injury hour (PIH). RESULTS: (1) Fiber bronchoscopic examination showed that the degree of inhalation injury in each group was coincident with the anticipation. (2) The serum content of iCT in each group at 1 PIH was obviously higher than that before injury, and it was evidently higher in A, B and C groups than that in D group at 4 PIH. The peak value of iCT in group A at 24 PIH was (453+/-224) ng/L, and it increased gradually in B and C groups at 48 PIH. The serum content of iCT increased continually from 2 PIH on, and it reached (125+/-41) ng/L at 48 PIH. (3) Compared with PaO2 value before injury (109+/-8) mmHg, there was no obvious difference of the PaO, in A and D groups. PaO2 value in B and C group began to descend continually at 8 PIH (65+/-6) mmHg, and that in C group began to descend at 4 PIH (71+/-9) mmHg. PaCO2 value in C group began to increase at 24 PIH(52+/-11) mmHg when compared with that before injury(38+/-5 ) mmHg. CONCLUSION: The changes in the serum level of iCT within 8 PIH occurred much earlier than PaO2 and PaCO2, thus it has the same diagnostic significance as fibers bronchoscopic examination.