OBJECTIVE: To assess the value of chromosomal microarray analysis (CMA) and trio-whole exome sequencing (trio-WES) for fetuses with increased nuchal translucency (NT) thickness. METHODS: Sixty two pregnant women who had visited Urumqi Maternal and Child Care Health Hospital between June 2018 and June 2020 for NT ≥ 3.0 mm at 11 ~ 13⁺⁶ gestational weeks were selected as study subjects. Relevant clinical data were collected. The patients were divided into 3.0 ~ ＜3.5 mm (n = 33) and ≥3.5 mm groups (n = 29). Chromosome karyotyping analysis and chromosomal microarray analysis were carried out. And trio-WES analysis was performed on 15 samples with NT thickening but negative CMA results. The distribution and incidence of chromosomal abnormalities in the two groups were compared by using chi-square test. RESULTS: The median age of the pregnant women was 29 years old (22 ~ 41 years old), the median thickness of NT was 3.4 mm (3.0 ~ 9.1 mm), and the median gestational age at the detection was 13⁺⁴ weeks (11⁺⁵ ~ 13⁺⁶ weeks). Chromosome karyotyping analysis has detected 12 cases of aneuploidies and 1 case of derivative chromosome. The detection rate was 20.97% (13/62). CMA has detected 12 cases of aneuploidies, 1 case of pathogenic CNV and 5 cases of variant of uncertain significance (VUS), with a detection rate of 29.03% (18/62). The aneuploidy rate for the NT ≥ 3.5 mm group was higher than that for the 3.0 ≤ NT < 3.5 mm group [3.03% (1/33) vs. 41.38% (12/29), χ² = 13.698, P < 0.001]. There was no statistically significant difference between the two groups in the detection rate of fetal pathogenic CNV and VUS (χ² = 0.028, P > 0.05). Trio-WES analysis of 15 samples with negative CMA result and no structural abnormality has identified 6 heterozygous variants, including SOS1: c.3542C>T (p.A1181V) and c.3817C>G (p.L1273V), COL2A1: c.436C>T (p.P146S) and c.3700G>A (p.D1234N), LZTR1: c.1496T>C (p.V499A), and BRAF: c.64G>A (p.D22N), respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), all of the variants were rated as VUS. CONCLUSION NT thickening can indicate chromosome abnormality, and CMA and trio-WES may be used for the prenatal diagnosis.
Pregnancy ; Humans ; Female ; Adult ; Infant ; Nuchal Translucency Measurement/methods* ; Prenatal Diagnosis/methods* ; Chromosome Aberrations ; Aneuploidy ; Fetus/diagnostic imaging* ; Ultrasonography, Prenatal ; DNA Copy Number Variations ; Transcription Factors

Objective:To investigate the protective effect and mechanism of dexamethasone in lung ischemia/reperfusion injury (LIRI) rats.Methods:① Part one experiment: 24 Sprague-Dawley (SD) rats were divided into four groups according to the random number method ( n = 6): standard ventilation group (N group), normal saline group (NS group), LIRI group, and dexamethasone+LIRI group (DEX group). The rat model of LIRI was established by clamping the left pulmonary hilum for 1 hour and reperfusing it for 2 hours. The DEX group was given dexamethasone 3 mg/kg 5 minutes before reperfusion, and NS group was injected with normal saline. Group N did not receive any treatment. The left lung tissue of the rats in each group were taken alive 2 hours after reperfusion. The lung tissue was harvested for lung wet/dry mass ratio (W/D) measurement. Hematoxylin-eosin (HE) staining and electron microscopy was used to observe the pathological changes of lung tissue and to assess the degree of injury. Ultrastructural changes of lung tissue were observed under electron microscope. The levels of tumor necrosis factor-α (TNF-α), interleukin (IL-1β, IL-6) in lung tissue were detected by enzyme linked immunosorbent assay (ELISA). The expressions of phosphorylated protein kinase B (p-AKT) was detected by Western Blot. ② Part two experiment: intervention with phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway inhibitor LY294002 to further explore the mechanism of dexamethasone in reducing lung injury induced by LIRI. Twenty-four SD rats were divided into four groups according to the random number method ( n = 6): N group, LIRI group, DEX group, and dexamethasone+LY294002+LIRI group (LY group). All the groups except the LY group were treated with membrane and intervention according to part one experiment. The LY group was injected with LY294002 0.3 mg/kg after injection of dexamethasone. The expressions of M1 macrophage polarization markers CD11c, CD16, and M2 macrophage polarization markers CD206, Arg1 were detected by immunohistochemistry. Results:① Part one experiment: compared with N group, the morphological and ultrastructural changes of lung tissue in the LIRI group were significantly changed, lung injury score, lung W/D ratio and TNF-α, IL-1β, IL-6 levels were significantly increased, and p-AKT expression was significantly decreased. Compared with the LIRI group, the morphological and ultrastructural changes of the lung tissue in the DEX group were significantly improved, and the lung injury score was reduced (5.00±0.89 vs. 8.83±0.75), lung W/D ratio and TNF-α, IL-1β, IL-6 levels were significantly decreased [lung W/D ratio: 6.25±0.56 vs. 8.27±0.72, TNF-α(ng/L): 93.28±16.42 vs. 205.90±25.30, IL-1β(ng/L): 130.10±10.81 vs. 209.10±19.20, IL-6 (ng/L): 195.80±21.17 vs. 310.50±20.77], p-AKT expression was significantly increased [p-AKT/AKT: (57.58±8.80)% vs. (36.62±9.25)%], and the differences were statistically significant (all P < 0.05). There was no significant difference in each index between NS group and N group. ② Part two experiment: compared with the N group, the expression of macrophage polarization markers CD11c, CD16, CD206 and Arg1 in the LIRI group were significantly increased. Compared with the LIRI group, the expressions of CD11c and CD16 in the lung tissue of the DEX group were significantly decreased, and the expressions of CD206 and Arg1 were significantly increased. The intervention of PI3K/AKT signaling pathway inhibitor LY294002 significantly blocked the effect of dexamethasone on LIRI-mediated macrophage polarization (CD11c immunohistochemical score: 7.20±0.36 vs. 5.00±0.34, CD16 immunohistochemical score: 8.20±0.48 vs. 7.40±0.64, CD206 immunohistochemical score: 5.80±0.59 vs. 7.40±0.28, Arg1 immunohistochemical score: 7.20±0.72 vs. 8.80±0.48, all P < 0.05). Conclusions:Dexamethasone pretreatment can alleviate the intrapulmonary inflammatory response and lung injury caused by LIRI in rats. The mechanism of action is related to the polarization direction of pulmonary macrophagesvia activation of the PI3K/AKT pathway by dexamethasone.

Objective:To establish a model of patellar dislocation by femoral osteotomy or surgical release of medial retinaculum in immature rabbits, and observe morphological and trabecular microarchitectural changes in the trochlea.Methods:Forty rabbits at 3 months of age were included. All right knees underwent surgery, 20 knees were treated with femoral osteotomy and internal rotation of distal femur to increase femoral anteversion angle (Osteotomy group, OS group), and another 20 knees were treated with surgical release of medial retinaculum and overlap suture of lateral retinaculum (Soft tissue group, ST group). All left knees were acting as internal controls. Micro-CT scans for distal femur were acquired after 4 months post surgery. the height of Medial, central, and lateral trochlear, sulcus angle, and lateral and medial trochlear slope were measured to describe the trochlear morphology, and bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular spacing (Tb.Sp), and bone mineral density (BMD) were calculated to evaluate the microarchitectural structure. All parameters were compared between groups.Results:In OS group, one rabbit sustained a hip dislocation without patellar dislocation. Three knees developed complete patellar dislocation in daily flexion position, and the remaining 16 patellae were dislocated when the knee was placed in the maximal extension position. In ST group, 15 knees were complete patellar dislocation in daily flexion position, and 5 knees were without dislocation. A local boss was formed proximal to the entrance of the groove and the articular cartilage was smooth, and no obvious osteoarthritis was observed in OS group. In ST group no boss was formed, while obvious cartilage degeneration and defect was seen. Compared to the control group, the central trochlear height and sulcus angle were greater in both groups, but without significant difference between the two groups. The Tb.Th was increased in both medial and lateral condyle, and Tb.N was decreased in medial condyle compared with its control knees in OS group. The BV/TV, Tb.Th, Tb.N and BMD were decreased and Tb.Sp was increased in both medial and lateral condyle compared with its control knees in ST group. Compared to the OS group, the BV/TV, Tb.Th, Tb.N and BMD were smaller and Tb.Sp was greater in both medial and lateral condyle in ST group, with significant differences.Conclusion:The model of patellar dislocation could be successfully achieved by femoral rotational osteotomy to increase femoral anteversion or surgical release of medial retinaculum and overlap suture of lateral retinaculum, and subsequent morphological and trabecular microarchitectural changes in the trochlea are different. Different bony and soft tissue factors should be addressed for different patients with patellar dislocation in clinical practice.

Objective:To investigate the effects of three monomer components stilbene glycoside, emodin, catechin of Polygonum multiflorum on damages of liver tissue and cell.Methods:A total of 48 rats were randomly divided into four groups of stilbene glycoside, emodin, catechin-and normal saline(control)-treated groups(n=12, each). Rats were gavaged with the same dose of 1 g/kg for stilbene glycoside, emodin, catechin groups and normal saline for control group for 28 days.During the administration, the general state of rat was observed.After the last administration, serum biochemical indexes related to liver function were detected.Pathological morphological changes of liver tissue were observed by hatmatoxylin-Eosin(HE)staining.The expression levels of apoptosis-related proteins in liver tissue were determined by Western blot.Cells of human normal liver cell line LO2 divided into the stilbene glycoside-, emodin-, catechin-treated cells groups were cultured with 7 different concentrations of interfering agents for 24 h and 48 h respectively, and cultured with normal saline in the control group for the same time.Cell proliferation was observed using the cholecystokinin octapeptide(CCK8), and the mRNA expressions of apoptosis-related factors were detected using PCR.Results:After 28 days of feeding, there was no significant difference in body weight and food intake among the four groups( P>0.05). Pathological liver damage and abnormal liver biochemical indexes were observed in rat liver tissues in the emodin and catechin groups( P<0.05). Compared with the control group, the expression levels of anti-apoptotic proteins Bcl-2 were decreased(0.34±0.03, 0.41±0.07 vs.0.45±0.04, P<0.05), the expression levels of apoptotic proteins Caspase-3 and Bax were increased(0.76±0.03, 0.27±0.06 vs.0.03±0.00; 0.44±0.03, 0.15±0.04 vs.0.02±0.00, P<0.01), and those in the stilbene glycoside group were normal.Compared with the control group, emodin and catechin-treated cell groups showed the concentration-and time-dependent proliferation inhibition in LO2 normal hepatocytes( P<0.05)after treatment.And the mRNA expression of hepatocyte apoptosis factors Bax and Caspase-3 were increased(1.74±0.05, 1.29±0.01 vs.0.89±0.12, 1.21±0.07, 1.25±0.01 vs.0.97±0.07, P<0.01), and that of anti-apoptotic proteins Bcl-2 was decreased(0.06±0.06, 0.56±0.11 vs.1.39±0.18, P<0.01). Compared with the control group, the survival rate had no significant difference in the stilbene glycoside treated-cell group( P>0.05), while its mRNA expression of hepatocyte apoptosis factors was reduced( P<0.05). Conclusions:No obvious liver damage is found in rats treated with the stilbene glycoside of Polygonum multiflorum, but the emodin and catechin cause damages of liver tissue and cell in vivo and in vitro.

Objective:This study was to systematically update the economic evaluation evidence of colorectal cancer screening in mainland China.Methods:Based on a systematic review published in 2015, we expanded the scope of retrieval database (PubMed, EMbase, The Cochrane Library, Web of Science, CNKI, Wanfang Data, VIP, CBM) and extended it to December 2018. Focusing on the evidence for nearly 10 years (2009-2018), basic characteristics and main results were extracted. Costs were discounted to 2017 using the consumer price index of medical and health care being provided to the residents, and the ratio of incremental cost-effectiveness ratio (ICER) to per capita GDP in corresponding years were calculated.Results:A total of 12 articles (8 new ones) were included, of which 9 were population-based (all cross-sectional studies) and 3 were model-based. Most of the initial screening age was 40 years (7 articles), and most of the frequency was once in a lifetime (11 articles). Technologies used for primary screening included: questionnaire assessment, immunological fecal occult blood test (iFOBT) and endoscopy. The most commonly used indicator was the cost per colorectal cancer detected, and the median (range) of the 20 screening schemes was 52 307 Chinese Yuan (12 967-3 769 801, n=20). The cost per adenoma detected was 9 220 Yuan (1 859-40 535, n=10). In 3 articles, the cost per life year saved (compared with noscreening) was mentioned and the ratio of ICER to GDP was 0.673 (-0.013-2.459, n=11), which was considered by WHO as "very cost-effective" ; The range of ratios overlapped greatly among different technologies and screening frequencies, but the initial age for screening seemed more cost-effective at the age of 50 years (0.002, -0.013-0.015, n=3), than at the 40 year-olds (0.781, 0.321-2.459, n=8). Conclusions:Results from the population-based studies showed that the cost per adenoma detected was only 1/6 of the cost per colorectal cancer detected, and limited ICER evidence suggested that screening for colorectal cancer was generally cost-effective in Chinese population. Despite the inconclusiveness of the optimal screening technology, the findings suggested that the initial screening might be more cost-effective at older age. No high-level evidence such as randomized controlled trial evaluation was found.

Objective:The existed economic evaluations of cancer screening in Chinese population are almost all single-cancer focused, evidence on parallel comparison among multiple cancers is lacking. Thus, the aim of this study was, from a priority setting perspective, to compare the cost-effectiveness of six common cancers(colorectal cancer, breast cancer, liver cancer, lung cancer, esophageal cancer and stomach cancer) to facilitate policy making in future scaled-up screening in populations in China.Methods:Partially based on our previous single-cancer systematic reviews (colorectal cancer, breast cancer, liver cancer, and lung cancer), evidence of economic evaluations of cancer screening in populations in mainland China were systematically updated and integrated. The main updates include: 1) Stomach cancer and esophageal cancer were newly added to the current analysis. 2) The literature searching was extended to 8 literature databases, including PubMed, EMbase, The Cochrane Library, Web of Science, CBM, CNKI, Wanfang Data, and VIP. 3) The period of publication year was updated to the recent 10 years: January 1, 2009 to December 31, 2018. 4) The study focused on populations in mainland China. Following the standard processes of literature searching, inclusion and exclusion from previous systematic reviews, the basic characteristics, evaluation indicators and main results of the included studies were extracted. All the costs were discounted to 2017 value using the by-year consumer price index of medical and health care residents in China and presented in the Chinese Yuan (CNY). The ratios of incremental cost-effectiveness ratio (ICER) to China′s per capita GDP in 2017 were calculated (<1 means very cost-effective, 1-3 means cost-effective, >3 means not cost-effective). Given a specific indicator, the median value among all reported screening strategies for each cancer was calculated, based on which priority ranking was then conducted among all cancers when data available.Results:A total of 45 studies were included, 22 for breast cancer, 12 for colorectal cancer, 6 for stomach cancer, 4 for esophageal cancer (all conducted in high-risk areas), 1 for liver cancer and none for lung cancer (was not then considered for next ranking due to limited numbers of studies). When based on the indicator, the median ratio of cost per life-year saved to China′s per capita GDP (reported in 12 studies), the lowest ratio (-0.015) was observed in esophageal cancer among 16 strategies of 2 studies ( N=2, n=16), followed by 0.297 for colorectal cancer ( N=3, n=12), 0.356 for stomach cancer ( N=1, n=4) and 0.896 for breast cancer ( N=6, n=52, P75=3.602). When based on another commonly used ICER indicator, the median ratio of cost per quality-adjusted life-year gained to China′s per capita GDP (reported in 13 studies), the least cost was found in stomach cancer (0.495, N=3, n=8, P75=3.126), followed by esophageal cancer (0.960, N=1, n=4, P75=1.762) and breast cancer (2.056, N=9, n=64, P75=4.217). Data was not found for colorectal cancer. In addition, cost per cancer case detected was the most adopted indicator (32 studies). The median cost among all screening strategies for each cancer was 14 759 CNY for stomach cancer ( N=5, n=7), 49 680 CNY for colorectal cancer ( N=12, n=25) and 171 930 CNY for breast cancer ( N=13, n=24), respectively. Data was not available for esophageal cancer and rare for precancer cases detected. Evidence related to cost per disability-adjusted life-year gained was not available. Conclusions:At China′s national level and limited to the six cancers covered by the current study, the preliminary analysis suggests that stomach cancer and colorectal cancer were the most cost-effective target cancers and could be given priority in the future scaled-up screening in general populations. Esophageal cancer screening should be prioritized in high-risk areas. Breast cancer was also cost-effective in general but some of the intensive screening strategies were marginal. Data on liver cancer and lung cancer were too limited to conclude, and more well-designed studies and high-quality research evidence should be required. This priority ranking might be changed if other common cancers were involved analyses.

Objective:The existed economic evaluations of cancer screening in Chinese population are almost all single-cancer focused, evidence on parallel comparison among multiple cancers is lacking. Thus, the aim of this study was, from a priority setting perspective, to compare the cost-effectiveness of six common cancers(colorectal cancer, breast cancer, liver cancer, lung cancer, esophageal cancer and stomach cancer) to facilitate policy making in future scaled-up screening in populations in China.Methods:Partially based on our previous single-cancer systematic reviews (colorectal cancer, breast cancer, liver cancer, and lung cancer), evidence of economic evaluations of cancer screening in populations in mainland China were systematically updated and integrated. The main updates include: 1) Stomach cancer and esophageal cancer were newly added to the current analysis. 2) The literature searching was extended to 8 literature databases, including PubMed, EMbase, The Cochrane Library, Web of Science, CBM, CNKI, Wanfang Data, and VIP. 3) The period of publication year was updated to the recent 10 years: January 1, 2009 to December 31, 2018. 4) The study focused on populations in mainland China. Following the standard processes of literature searching, inclusion and exclusion from previous systematic reviews, the basic characteristics, evaluation indicators and main results of the included studies were extracted. All the costs were discounted to 2017 value using the by-year consumer price index of medical and health care residents in China and presented in the Chinese Yuan (CNY). The ratios of incremental cost-effectiveness ratio (ICER) to China′s per capita GDP in 2017 were calculated (<1 means very cost-effective, 1-3 means cost-effective, >3 means not cost-effective). Given a specific indicator, the median value among all reported screening strategies for each cancer was calculated, based on which priority ranking was then conducted among all cancers when data available.Results:A total of 45 studies were included, 22 for breast cancer, 12 for colorectal cancer, 6 for stomach cancer, 4 for esophageal cancer (all conducted in high-risk areas), 1 for liver cancer and none for lung cancer (was not then considered for next ranking due to limited numbers of studies). When based on the indicator, the median ratio of cost per life-year saved to China′s per capita GDP (reported in 12 studies), the lowest ratio (-0.015) was observed in esophageal cancer among 16 strategies of 2 studies ( N=2, n=16), followed by 0.297 for colorectal cancer ( N=3, n=12), 0.356 for stomach cancer ( N=1, n=4) and 0.896 for breast cancer ( N=6, n=52, P75=3.602). When based on another commonly used ICER indicator, the median ratio of cost per quality-adjusted life-year gained to China′s per capita GDP (reported in 13 studies), the least cost was found in stomach cancer (0.495, N=3, n=8, P75=3.126), followed by esophageal cancer (0.960, N=1, n=4, P75=1.762) and breast cancer (2.056, N=9, n=64, P75=4.217). Data was not found for colorectal cancer. In addition, cost per cancer case detected was the most adopted indicator (32 studies). The median cost among all screening strategies for each cancer was 14 759 CNY for stomach cancer ( N=5, n=7), 49 680 CNY for colorectal cancer ( N=12, n=25) and 171 930 CNY for breast cancer ( N=13, n=24), respectively. Data was not available for esophageal cancer and rare for precancer cases detected. Evidence related to cost per disability-adjusted life-year gained was not available. Conclusions:At China′s national level and limited to the six cancers covered by the current study, the preliminary analysis suggests that stomach cancer and colorectal cancer were the most cost-effective target cancers and could be given priority in the future scaled-up screening in general populations. Esophageal cancer screening should be prioritized in high-risk areas. Breast cancer was also cost-effective in general but some of the intensive screening strategies were marginal. Data on liver cancer and lung cancer were too limited to conclude, and more well-designed studies and high-quality research evidence should be required. This priority ranking might be changed if other common cancers were involved analyses.

Objective: To investigate the role and mechanism of Ly6C^high monocyte in mice with ventilator-induced lung injury (VILI). Methods: Forty-eight healthy male SPF C57BL/6 mice were divided into spontaneous breathing group (n = 8), normal tidal volume (VT) group (VT was 8 mL/kg, n = 8), and high VT group (VT was 20 mL/kg, n = 32). The mice in the high VT group were subdivided into 1, 2, 3 and 4 hours subgroups, with 8 mice in each subgroup. All mice underwent direct tracheal intubation, those in the spontaneous breathing group maintained spontaneous breathing, and those in the normal VT group and high VT group were mechanically ventilated with different VT. After ventilation for 4 hours, bronchoalveolar lavage fluid (BALF) was collected to determine total protein, and the levels of inflammatory factors including tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were determined by enzyme-linked immune sorbent assay (ELISA). The lung tissues were harvested to determine the wet/dry (W/D) ratio, and lung tissue injury was assessed in terms of lung histopathologic examination after hematoxylin-eosin (HE) staining under the light microscope. The protein expressions of monocyte chemotactic protein-1 (MCP-1) and CC-chemokine receptor 2 (CCR2) in lung tissues were determined by Western Blot. Flow cytometry was used to detect the proportion of Ly6C^high monocyte in lung tissue. Results: The histopathology of lung tissue structures was normal in the spontaneous breathing group and the normal VT group. Inflammatory reaction began to appear at 2 hours of high VT ventilation, and inflammatory reaction was gradually aggravated with the time extension. Compared with the spontaneous breathing group, the total protein, TNF-α, and IL-1β levels in BALF, the lung W/D ratio and MCP-1 expression were increased from 2 hours of high VT ventilation [total protein in BALF (g/L): 1.05±0.13 vs. 0.58±0.11, TNF-α in BALF (ng/L): 116.86±16.14 vs. 38.27±8.00, IL-1β in BALF (ng/L): 178.98±10.41 vs. 117.56±23.40, lung W/D ratio: 5.76±0.27 vs. 4.98±0.39, MCP-1/GAPDH: 0.87±0.19 vs. 0.29±0.12, all P < 0.05], and CCR2 expression and the proportion of Ly6C^high monocyte was significantly increased from 3 hours of high VT ventilation [CCR2/GAPDH: 0.84±0.19 vs. 0.24±0.11, Ly6C^high monocyte proportion: (9.01±2.47)% vs. (1.06±0.35)%, both P < 0.05], and they all showed an increased tendency with the time extension. There was no significant difference in the parameters mentioned above among the spontaneous breathing group, normal VT group and high VT ventilation 1-hour group. Conclusion Ly6C^high monocytes are involved in VILI, which aggravate VILI by activating the MCP-1/CCR2 axis.

OBJECTIVE: To investigate the relationship between different tidal volume (VT) mechanical ventilation (MV) and autophagy and mitochondrial damage in rats. METHODS: A total of 120 clean-grade male Sprague-Dawley (SD) rats were divided into five groups (n = 24) by random number table method, and then given 0 (spontaneous breathing), 10, 20, 30, 40 mL/kg VT for MV. The rats in each group were subdivided into four subgroups of 1, 2, 3, and 4 hours according to ventilation time, with 6 rats in each subgroup. The lung tissue and bronchoalveolar lavage fluid (BALF) were harvested, and alveolar macrophages (AMs) and type II alveolar epithelial cells (AEC II) were cultured in vitro. The mRNA and protein expressions of autophagy-associated protein microtubule-associated protein 1 light chain 3B-II (LC3B-II) and autophagy-related genes Beclin1 and p62 were determined by reverse transcription-polymerase chain reaction (RT-PCR) or Western Blot. Lung autophagosome formation was observed under transmission electron microscope. The levels of adenosine triphosphate (ATP), reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) in lung tissue were determined for assessing mitochondrial damage. RESULTS: There were no significant differences in the mRNA and protein expressions of LC3B-II, p62 and Beclin1 at 1 hour after ventilation among the groups. With the prolonged ventilation time, the mRNA and protein expressions of LC3B-II, p62 and Beclin1 in MV groups were increased gradually, peaked at 2-3 hours, and they were increased significantly in 30 mL/kg VT group as compared with those in spontaneous respiration group with statistical significances [ventilation for 2 hours: LC3B-II mRNA (2^-ΔΔCt) was 2.44±0.24 vs. 1.12±0.04, LC3B-II/LC3B-I was 1.42±0.16 vs. 0.57±0.03, p62 mRNA (2^-ΔΔCt) was 2.96±0.14 vs. 1.14±0.02, Beclin1 mRNA (2^-ΔΔCt) was 2.80±0.13 vs. 1.14±0.02; ventilation for 3 hours: p62/β-actin was 1.14±0.15 vs. 0.55±0.04, Beclin1/β-actin was 1.27±0.06 vs. 0.87±0.04, all P < 0.05]. Autophagosomes and autolysosomes were found in AEC II after ventilation for 2 hours at 30 mL/kg VT by transmission electron microscopy, but not in AEC I. Compared with spontaneous breathing group, ATP synthesis in AMs was significantly decreased at 2 hours of ventilation in 30 mL/kg VT group (A value: 0.82±0.05 vs. 1.00±0.00, P < 0.05), ROS accumulate in AMs and AEC II were significantly increased [ROS in AMs: (33.83±4.00)% vs. (6.90±0.62)%, ROS in AEC II: (80.68±0.90)% vs. (2.16±0.19)%, both P < 0.05]. With the increase in VT and the prolongation of ventilation time, ATP and ROS levels in AMs and AEC II were gradually decreased, the ATP (A value) in AMs at 4 hours of ventilation in 40 mL/kg VT group was 0.41±0.05, the ROS in AMs was (12.95±0.88)%, and the ROS in AEC II was (40.43±2.29)%. With the increase in VT and the prolongation of ventilation time, MMP levels were gradually increased, the MMP (green/red fluorescence intensity ratio) in AMs at 2 hours of ventilation in 30 mL/kg VT group was 1.11±0.17, the MMP in AEC II was 0.96±0.04, and the MMP (green/red fluorescence intensity ratio) at 4 hours of ventilation in 40 mL/kg VT group was 0.51±0.07 and 0.49±0.06, respectively. CONCLUSIONS The MV with high VT could induce autophagy activation and mitochondrial damage in lung tissue of rats, and the longer the ventilation time, the more obvious autophagy in the lung.
Animals ; Autophagy/physiology* ; Male ; Mitochondria/pathology* ; Rats ; Rats, Sprague-Dawley ; Respiration, Artificial/adverse effects* ; Tidal Volume ; Time Factors ; Ventilator-Induced Lung Injury

OBJECTIVE: To investigate the role and mechanism of Ly6C^high monocyte in mice with ventilator-induced lung injury (VILI). METHODS: Forty-eight healthy male SPF C57BL/6 mice were divided into spontaneous breathing group (n = 8), normal tidal volume (VT) group (VT was 8 mL/kg, n = 8), and high VT group (VT was 20 mL/kg, n = 32). The mice in the high VT group were subdivided into 1, 2, 3 and 4 hours subgroups, with 8 mice in each subgroup. All mice underwent direct tracheal intubation, those in the spontaneous breathing group maintained spontaneous breathing, and those in the normal VT group and high VT group were mechanically ventilated with different VT. After ventilation for 4 hours, bronchoalveolar lavage fluid (BALF) was collected to determine total protein, and the levels of inflammatory factors including tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were determined by enzyme-linked immune sorbent assay (ELISA). The lung tissues were harvested to determine the wet/dry (W/D) ratio, and lung tissue injury was assessed in terms of lung histopathologic examination after hematoxylin-eosin (HE) staining under the light microscope. The protein expressions of monocyte chemotactic protein-1 (MCP-1) and CC-chemokine receptor 2 (CCR2) in lung tissues were determined by Western Blot. Flow cytometry was used to detect the proportion of Ly6C^high monocyte in lung tissue. RESULTS: The histopathology of lung tissue structures was normal in the spontaneous breathing group and the normal VT group. Inflammatory reaction began to appear at 2 hours of high VT ventilation, and inflammatory reaction was gradually aggravated with the time extension. Compared with the spontaneous breathing group, the total protein, TNF-α, and IL-1β levels in BALF, the lung W/D ratio and MCP-1 expression were increased from 2 hours of high VT ventilation [total protein in BALF (g/L): 1.05±0.13 vs. 0.58±0.11, TNF-α in BALF (ng/L): 116.86±16.14 vs. 38.27±8.00, IL-1β in BALF (ng/L): 178.98±10.41 vs. 117.56±23.40, lung W/D ratio: 5.76±0.27 vs. 4.98±0.39, MCP-1/GAPDH: 0.87±0.19 vs. 0.29±0.12, all P < 0.05], and CCR2 expression and the proportion of Ly6C^high monocyte was significantly increased from 3 hours of high VT ventilation [CCR2/GAPDH: 0.84±0.19 vs. 0.24±0.11, Ly6C^high monocyte proportion: (9.01±2.47)% vs. (1.06±0.35)%, both P < 0.05], and they all showed an increased tendency with the time extension. There was no significant difference in the parameters mentioned above among the spontaneous breathing group, normal VT group and high VT ventilation 1-hour group. CONCLUSIONS Ly6C^high monocytes are involved in VILI, which aggravate VILI by activating the MCP-1/CCR2 axis.
Animals ; Antigens, Ly/metabolism* ; Lung ; Male ; Mice ; Mice, Inbred C57BL ; Monocytes ; Rats ; Rats, Sprague-Dawley ; Tidal Volume ; Tumor Necrosis Factor-alpha ; Ventilator-Induced Lung Injury