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Chromosomal-level genome and metabolome analyses of highly heterozygous allohexaploid Dendrocalamus brandisii elucidate shoot quality and developmental characteristics. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023. [PMID: 38051011 DOI: 10.1111/jipb.13592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/17/2023] [Accepted: 12/04/2023] [Indexed: 12/07/2023]
Abstract
Dendrocalamus brandisii (Munro) Kurz is a sympodial bamboo species with inimitable taste and flavorful shoots. Its rapid growth and use as high-quality material make this bamboo species highly valued for both food processing and wood applications. However, genome information for D. brandisii is lacking, primarily due to its polyploidy and large genome size. Here, we assembled a high-quality genome for hexaploid D. brandisii, which comprises 70 chromosomes with a total size of 2,756 Mb, using long-read HiFi sequencing. Furthermore, we accurately separated the genome into its three constituent subgenomes. We used Oxford Nanopore Technologies long reads to construct a transcriptomic dataset covering 15 tissues for gene annotation to complement our genome assembly, revealing differential gene expression and post-transcriptional regulation. By integrating metabolome analysis, we unveiled that well-balanced lignin formation, as well as abundant flavonoid and fructose contents, contribute to the superior quality of D. brandisii shoots. Integrating genomic, transcriptomic, and metabolomic datasets provided a solid foundation for enhancing bamboo shoot quality and developing efficient gene-editing techniques. This study should facilitate research on D. brandisii and enhance its use as a food source and wood material by providing crucial genomic resources.
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Polymer composite microspheres loading 177Lu radionuclide for interventional radioembolization therapy and real-time SPECT imaging of hepatic cancer. Biomater Res 2023; 27:110. [PMID: 37925456 PMCID: PMC10625707 DOI: 10.1186/s40824-023-00455-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 10/24/2023] [Indexed: 11/06/2023] Open
Abstract
BACKGROUND Transarterial radioembolization (TARE) with 90Y-labeled glass and resin microspheres is one of the primary treatment strategies for advanced-stage primary and metastatic hepatocellular carcinoma (HCC). However, difficulties of real-time monitoring post administration and embolic hypoxia influence treatment prognosis. In this study, we developed a new biodegradable polymer microsphere that can simultaneously load 177Lu and MgO nanoparticle, and evaluated the TARE therapeutic efficacy and biosafety of 177Lu-PDA-CS-MgO microspheres for HCC treatment. METHODS Chitosan microspheres were synthesized through emulsification crosslink reaction and then conducted surface modification with polydopamine (PDA). The 177Lu and nano MgO were conjugated to microspheres using active chemical groups of PDA. The characteristics of radionuclide loading efficiency, biodegradability, blood compatibility, and anti-tumor effectwere evaluated both in vitro and in vivo. SPECT/CT imaging was performed to monitor bio-distribution and bio-stability of 177Lu-PDA-CS-MgO after TARE treatment. The survival duration of each rat was monitored. HE analysis, TUNEL analysis, immunohistochemical analysis, and western blot analysis were conducted to explore the anti-tumor effect and mechanism of composited microspheres. Body weight, liver function, blood routine examination were monitored at different time points to evaluate the bio-safety of microspheres. RESULTS The composite 177Lu-PDA-CS-MgO microsphere indicated satisfactory degradability, biocompatibility, radionuclide loading efficiency and radiochemical stability in vitro. Cellular evaluation showed that 177Lu-PDA-CS-MgO had significant anti-tumor effect and blocked tumor cell cycles in S phase. Surgical TARE treatment with 177Lu-PDA-CS-MgO significantly prolonged the medial survival time from 49 d to 105 d, and effectively inhibited primary tumor growth and small metastases spreading. Moreover, these microspheres indicated ideal in vivo stability and allowed real-time SPECT/CT monitoring for up to 8 weeks. Immunostaining and immunoblotting results also confirmed that 177Lu-PDA-CS-MgO had potential in suppressing tumor invasion and angiogenesis, and improved embolic hypoxia in HCC tissues. Further evaluations of body weight, blood test, and pathological analysis indicated good biosafety of 177Lu-PDA-CS-MgO microspheres in vivo. CONCLUSION Our study demonstrated that 177Lu-PDA-CS-MgO microsphere hold great potential as interventional brachytherapy candidate for HCC therapy. Polymer composite microspheres loading 177Lu radionuclide and MgO nanoparticles for interventional radioembolization therapy and real-time SPECT imaging of hepatic cancer.
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Copper deprivation enhances the chemosensitivity of pancreatic cancer to rapamycin by mTORC1/2 inhibition. Chem Biol Interact 2023; 382:110546. [PMID: 37290678 DOI: 10.1016/j.cbi.2023.110546] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 05/07/2023] [Accepted: 05/15/2023] [Indexed: 06/10/2023]
Abstract
Cuproplasia, or copper-dependent cell proliferation, has been observed in varieties of solid tumors along with aberrant copper homeostasis. Several studies reported good response of patients to copper chelator assisted neoadjuvant chemotherapy, however, the internal target molecules are still undetermined. Unravel copper-associated tumor signaling would be valuable to forge new links to translate biology of copper into clinical cancer therapies. We evaluated the significance of high-affinity copper transporter-1 (CTR1) by bioinformatic analysis, and in 19 pairs of clinical specimens. Then, with the help of gene interference and chelating agent, enriched signaling pathways were identified by KEGG analysis and immunoblotting. Accompanying biological capability of pancreatic carcinoma-associated proliferation, cell cycle, apoptosis, and angiogenesis were investigated. Furthermore, a combination of mTOR inhibitor and CTR1 suppressor has been assessed in xenografted tumor mouse models. Hyperactive CTR1 was investigated in pancreatic cancer tissues and proven to as the key point of cancer copper homeostasis. Intracellular copper deprivation induced by CTR1 gene knock-down or systematic copper chelation by tetrathiomolybdate suppressed proliferation and angiogenesis of pancreatic cancer cell. PI3K/AKT/mTOR signaling pathway was suppressed by inhibiting the activation of p70(S6)K and p-AKT, and finally inhibited mTORC1 and mTORC2 after copper deprivation. Additionally, CTR1 gene silencing successfully improved the anti-cancer effect of mTOR inhibitor rapamycin. Our study reveals that CTR1 contributes to pancreatic tumorigenesis and progression, by up-regulating the phosphorylation of AKT/mTOR signaling molecules. Recovering copper balance by copper deprivation addresses as promising strategy for improved cancer chemotherapy.
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Single-cell transcriptome atlas reveals spatiotemporal developmental trajectories in the basal roots of moso bamboo ( Phyllostachys edulis). HORTICULTURE RESEARCH 2023; 10:uhad122. [PMID: 37554343 PMCID: PMC10405134 DOI: 10.1093/hr/uhad122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 06/01/2023] [Indexed: 08/10/2023]
Abstract
Roots are essential for plant growth and development. Bamboo is a large Poaceae perennial with 1642 species worldwide. However, little is known about the transcriptional atlas that underpins root cell-type differentiation. Here, we set up a modified protocol for protoplast preparation and report single-cell transcriptomes of 14 279 filtered single cells derived from the basal root tips of moso bamboo. We identified four cell types and defined new cell-type-specific marker genes for the basal root. We reconstructed the developmental trajectories of the root cap, epidermis, and ground tissues and elucidated critical factors regulating cell fate determination. According to in situ hybridization and pseudotime trajectory analysis, the root cap and epidermis originated from a common initial cell lineage, revealing the particularity of bamboo basal root development. We further identified key regulatory factors for the differentiation of these cells and indicated divergent root developmental pathways between moso bamboo and rice. Additionally, PheWOX13a and PheWOX13b ectopically expressed in Arabidopsis inhibited primary root and lateral root growth and regulated the growth and development of the root cap, which was different from WOX13 orthologs in Arabidopsis. Taken together, our results offer an important resource for investigating the mechanism of root cell differentiation and root system architecture in perennial woody species of Bambusoideae.
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Identification of the effect and mechanism of Yiyi Fuzi Baijiang powder against colorectal cancer using network pharmacology and experimental validation. Front Pharmacol 2022; 13:929836. [PMID: 36353478 PMCID: PMC9637639 DOI: 10.3389/fphar.2022.929836] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 10/03/2022] [Indexed: 12/22/2023] Open
Abstract
Background: Yiyi Fuzi Baijiang powder (YFBP) is a traditional Chinese medicine used to treat colorectal cancer, although its bioactivity and mechanisms of action have not been studied in depth yet. The study intended to identify the potential targets and signaling pathways affected by YFBP during the treatment of colorectal cancer through pharmacological network analysis and to further analyze its chemical compositions and molecular mechanisms of action. Methods: The Traditional Chinese Medicine Systems Pharmacology (TCMSP), Traditional Chinese Medicine Integrated Database (TCMID), HitPredict (HIT), and Search Tool for Interactions of Chemicals (STITCH) databases were used to screen the bioactive components and promising targets of YFBP. Targets related to colorectal cancer were retrieved from the GeneCards and Gene Ontology databases. Cytoscape software was used to construct the "herb-active ingredient-target" network. The STRING database was used to construct and analyze protein-protein interactions (PPIs). Afterward, the R packages clusterProfiler and Cytoscape Hub plug-in were used to perform Gene Ontology (GO) functional and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of target genes. The results of the network pharmacological analysis were also experimentally validated. Results: In total, 33 active components and 128 target genes were screened. Among them, 46 target genes were considered potential therapeutic targets that crossed the CRC target genes. The network pharmacology analysis showed that the active components of YFBP were correlated positively with CRC inflammatory target genes such as TLR4, TNF, and IL-6. The inflammation-related signaling pathways affected by the active components included the TNF-α, interleukin-17, and toll-like receptor signaling pathways. The active ingredients of YFBP, such as luteolin, β-sitosterol, myristic acid, and vanillin, may exert anti-tumor effects by downregulating SMOX expression via anti-inflammatory signaling and regulation of the TLR4/NF-κB signaling pathway. Conclusion: In the present study, the potential active components, potential targets, and key biological pathways involved in the YFBP treatment of CRC were determined, providing a theoretical foundation for further anti-tumor research.
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Immunohistochemical evaluation of immune checkpoint antigens and stem cell markers on early versus late passage organoids from urothelial carcinoma cells. Eur Urol 2022. [DOI: 10.1016/s0302-2838(22)01144-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Usnic Acid Inhibits Proliferation and Migration through ATM Mediated DNA Damage Response in RKO Colorectal Cancer Cell. Curr Pharm Biotechnol 2021; 22:1129-1138. [PMID: 33006536 DOI: 10.2174/1389201021666201002155955] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/02/2020] [Accepted: 09/01/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Usnic Acid (UA), also known as lichenol, has been reported to have inhibitory effects on a variety of cancer cells, but its specific mechanism remained to be elucidated. Tumor chemotherapy drugs, especially DNA damage chemotherapeutic drugs, target Chromosomal DNA, but their spontaneous and acquired drug resistance are also an urgent problem to be solved. Therefore, drug combination research has become the focus of researchers. METHODS Here, we evaluated the tumor-suppressing molecular mechanism of UA in colorectal cancer cells RKO from the perspective of the ATM-mediated DNA damage signaling pathway through H2O2 simulating DNA damage chemotherapeutic drugs. CCK8 cell proliferation assay was used to determine the inhibition of RKO cells by hydrogen peroxide and UA alone or in combination, and wound healing assay was applied to determine the effect of the drug on cell migration. RESULTS Transfected cells with miRNA18a-5p mimics and inhibitors, MDC and DCFH-DA staining for the measurement of autophagy and ROS, cell cycle and apoptosis were detected by flow cytometry, expressions of microRNA and mRNA were determined by fluorescence quantitative PCR, and protein by Western blot. DISCUSSION We found that UA can upregulate ATM via miR-18a to activate the DNA damage signaling pathway and inhibit the proliferation and migration of RKO cells in a concentration-dependent manner. CONCLUSION At the same time, DNA damage responses, including cell cycle, autophagy, apoptosis and ROS levels, are also regulated by UA. Therefore, UA combined with DNA damage chemotherapeutic drugs may be an effective treatment for cancer.
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EGCG synergizes the therapeutic effect of irinotecan through enhanced DNA damage in human colorectal cancer cells. J Cell Mol Med 2021; 25:7913-7921. [PMID: 34132471 PMCID: PMC8358867 DOI: 10.1111/jcmm.16718] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 05/15/2021] [Accepted: 05/26/2021] [Indexed: 01/30/2023] Open
Abstract
Irinotecan is a kind of alkaloid with antitumour activity, but its low solubility and high toxicity limit its application. Epigallocatechin‐3‐gallate (EGCG) is one of the main bioactive components in tea. The epidemiological investigation and animal and cell experiments show that EGCG has a preventive and therapeutic effect on many kinds of tumours. Here, colorectal cancer cells RKO and HCT116 were employed, and the CCK8 proliferation test was used to screen the appropriate concentration of EGCG and irinotecan, and the effects of single and/or combined drugs on migration, invasion, DNA damage, cell cycle and autophagy of tumour cells were investigated. The results showed that EGCG combined with irinotecan (0.5 μmol L−) not only had a stronger inhibitory effect on tumour cells than EGCG or irinotecan alone but also prevented tumour cell migration and invasion. EGCG alone did not cause DNA damage in colorectal cancer cells, but its combination with irinotecan could induce S or G2 phase arrest by inhibiting topoisomerase I to cause more extensive DNA damage. EGCG also induced apoptosis by promoting autophagy with irinotecan synergistically. These results indicated that EGCG in combination with irinotecan could be a promising strategy for colorectal cancer.
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[Study on the relationship between occupational stress and metabolic syndrome in operating room nursing staff of a third-class A hospital]. ZHONGHUA LAO DONG WEI SHENG ZHI YE BING ZA ZHI = ZHONGHUA LAODONG WEISHENG ZHIYEBING ZAZHI = CHINESE JOURNAL OF INDUSTRIAL HYGIENE AND OCCUPATIONAL DISEASES 2020; 38:839-842. [PMID: 33287478 DOI: 10.3760/cma.j.cn121094-20191015-00496] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Objective: To explore the relationship between occupational stress and metabolic syndrome (MS) in operating room nurses. Methods: In July 2019, 179 nurses in the operating room of a third-class A hospital in Shandong Province were selected as the research objects. The self-designed questionnaire was used to investigate the general situation, and "Nurse Job Stressor Scale" was used to investigate the occupational stress level of nursing staff. The height, weight, waist circumference, blood pressure, fasting blood glucose, total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, ischemia-modified albumin, lipoprotein associated phospholipase A2 were measured. The nursing staff were divided into MS group and non-MS group, and the occupational stress levels of the two groups were compared. Chi square test or Fisher test were used to compare the counting data between groups; the measurement data were expressed by Mean±SD, and the comparison between groups was performed with t test. Multiple logistic regression analysis was used to analyze the influencing factors of MS. Results: The overall occupational stress level of nurses in operating room was (450.58±141.77) points, which was significantly lower than the norm score (P<0.05) ; Compared with non-MS group, the overall occupational stress level, work nature, workload and patient related factors in MS group were significantly higher, and the differences were statistically significant (P<0.05) ; The prevalence of abdominal obesity, hypertriglyceridemia, hyperglycemia and hypertension were significantly different among the groups with different occupational stress levels (P<0.05) . After adjusting waist circumference, triglyceride, systolic blood pressure, high density lipoprotein, ischemia modified albumin and lipoprotein associated phospholipase A2, the total score of occupational stress was the risk factor of MS in operating room nurses (P<0.05) . Conclusion: The occupational stress level of nurses in operating room is related to the prevalence of MS.
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Myeloid leukemia with high EVI1 expression is sensitive to 5-aza-2'-deoxycytidine by targeting miR-9. Clin Transl Oncol 2019; 22:137-143. [PMID: 31054042 DOI: 10.1007/s12094-019-02121-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 04/19/2019] [Indexed: 12/15/2022]
Abstract
PURPOSE High expression of ecotropic viral integration site 1 (EVI1) has been associated with a poor prognosis in leukemia patients, but the underlying mechanism remains unclear. Aberrant expression of microRNAs plays critical roles in leukemia development. MiR-9 is a putative potential target of EVI1. We have investigated the regulating mechanism of miR-9 by EVI1 in leukemia cells. METHODS We first examined the relationship between miR-9 and EVI1 expression levels in nine leukemia cell lines by RT-PCR. Then we forced high expression of EVI1 in UoCM1 and K562 cells to confirm the downregulation of miR-9 by EVI1. Methylation of the miR-9 promoter region was detected by DNA bisulfite sequencing. We treated the EVI1-overexpressing cells with the hypomethylating agent 5-aza-2'-deoxycytidine (5-AZA) to reverse EVI1-induced hypermethylation of miR-9. RESULTS EVI1 and miR-9 expression was negative related. Forced expression of EVI1 downregulated miR-9 by inducing hypermethylation of the miR-9 promoter. 5-AZA reversed high EVI1-induced hypermethylation of the miR-9 promoter and restored the expression of miR-9. 5-AZA induced extensive apoptosis and inhibited proliferation through cell cycle arrest in EVI1-overexpressing leukemia cells. CONCLUSIONS Our results suggest that EVI1 may be involved in leukemia cell proliferation and apoptosis via the regulation of miR-9 promoter methylation. 5-AZA may represent a promising therapeutic option for EVI1-high leukemia patients.
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The level of soluble programmed death ligand-1 in lung cancer: An exploratory biomarker study. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw363.22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Downregulation of CDC27 inhibits the proliferation of colorectal cancer cells via the accumulation of p21Cip1/Waf1. Cell Death Dis 2016; 7:e2074. [PMID: 26821069 PMCID: PMC4816181 DOI: 10.1038/cddis.2015.402] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 12/01/2015] [Accepted: 12/03/2015] [Indexed: 12/14/2022]
Abstract
Dysregulated cell cycle progression has a critical role in tumorigenesis. Cell division cycle 27 (CDC27) is a core subunit of the anaphase-promoting complex/cyclosome, although the specific role of CDC27 in cancer remains unknown. In our study, we explored the biological and clinical significance of CDC27 in colorectal cancer (CRC) growth and progression and investigated the underlying molecular mechanisms. Results showed that CDC27 expression is significantly correlated with tumor progression and poor patient survival. Functional assays demonstrated that overexpression of CDC27 promoted proliferation in DLD1 cells, whereas knockdown of CDC27 in HCT116 cells inhibited proliferation both in vitro and in vivo. Further mechanistic investigation showed that CDC27 downregulation resulted in G1/S phase transition arrest via the significant accumulation of p21 in HCT116 cells, and the upregulation of CDC27 promoted G1/S phase transition via the attenuation of p21 in DLD1 cells. Furthermore, we also demonstrated that CDC27 regulated inhibitor of DNA binding 1 (ID1) protein expression in DLD1 and HCT116 cells, and rescue assays revealed that CDC27 regulated p21 expression through modulating ID1 expression. Taken together, our results indicate that CDC27 contributes to CRC cell proliferation via the modulation of ID1-mediated p21 regulation, which offers a novel approach to the inhibition of tumor growth. Indeed, these findings provide new perspectives for the future study of CDC27 as a target for CRC treatment.
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27PD Plasma miRNA-based signatures to predict 3-year postoperative recurrence risk for patients with stage II and III gastric cancer. Ann Oncol 2015. [DOI: 10.1093/annonc/mdv518.02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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[High frequency oscillatory ventilation with perfluorocarbon in rabbits with acute lung injury]. ZHONGHUA YI XUE ZA ZHI 2001; 81:97-101. [PMID: 11798859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To investigate the efficacy of high frequency oscillation with perfluorocarbon (PFC) in rabbits with acute lung injury (ALI). METHODS Twenty four rabbits with ALI induced by repeated saline lung lavage were randomly assigned to four groups: conventional mechanical ventilation (CMV) group, CMV + PFC group, high frequency oscillation (HFO) group and HFO + PFC group. All rabbits were ventilated for two hours. Blood gases, respiratory system dynamic compliance (Cdyn) and intrapulmonary shunt fraction (Qs/Qt) were measured and calculated at 30, 60, and 120 min during experiment. RESULTS Compared with the CMV, statistically improvements were shown in gas exchange, Cdyn and Qs/Qt at 30 min in the CMV + PFC group [PaO(2) 122 mm Hg +/- 15 mm Hg vs. 692 mm Hg +/- 82 mm Hg, PaCO(2) 29.1 mm Hg +/- 2.7 mm Hg vs. 47.1 mm Hg +/- 2.9 mm Hg, Cdyn (1.35 +/- 0.13) vs (0.97 +/- 0.13) ml.cm H(2)O(-1).kg(-1), Qs/Qt 18.1 +/- 1.1 vs.24.5 +/- 2.9] (P < 0.01 approximately 0.05) and remained stable for two hours. Compared with HFO, HFO + PFC improved oxygenation and ventilation more rapidly than HFO did. At 30 min intervals gas exchange and Qs/Qt were significantly improved (PaO(2) 174.9 +/- 18.5 vs 132.3 +/- 19.4, PaCO(2) 26.1 +/- 2.6 vs 34.9 +/- 4.6, Qs/Qt 17.1 +/- 2.4 vs 19.8 +/- 0.9) (P < 0.05)and remained stable to 60 min. The same differences were seen at 60 min. CONCLUSION In rabbits with ALI, CMV + PFC could induce a significant improvement in gas exchange and Cdyn. HFO + PFC leads more rapidmy to reach best gas exchange and Cdyn.
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Experimental study of double-lumen, two-stage endotracheal tube during conventional mechanical ventilation in rabbits. Crit Care Med 1997; 25:492-5. [PMID: 9118667 DOI: 10.1097/00003246-199703000-00019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To evaluate the effects of a double-lumen, two-stage endotracheal tube on gas exchanges (ventilatory efficiency) during conventional mechanical ventilation, using a ventilator in rabbits. DESIGN Prospective, randomized, crossover laboratory animal trial. SETTING Research laboratory in the Beijing Children's Hospital. SUBJECTS Five adult New Zealand rabbits, weighing 3.2 to 3.7 kg. INTERVENTIONS A new type of endotracheal tube-the double-lumen two-stage endotracheal tube-was designed and tested for ventilation efficiency in rabbits with normal and injured lungs. The new tube (size 3.0 mm) was made out of two Portex endotracheal tubes (size 3.0 mm) by adhering two vertical cross-sections at the distal end of the two tubes. The new tube and a conventional endotracheal tube of the same size (inner diameter 3.0 mm) were randomly used in pressure control ventilation. Each trial was maintained for 30 mins. MEASUREMENTS AND MAIN RESULTS Effects from the two endotracheal tubes on pulmonary mechanics, hemodynamics, and gas exchange were observed. We measured peak inspiratory pressure, positive end-expiratory pressure (PEEP), intrinsic PEEP, mean airway pressure, and arterial blood and mixed expired gas variables (Pao2, Paco2, pH, and mixed expired gas Pco2). The new endotracheal tube acutely increased CO2 elimination in all animals with normal and injured lungs. Paco2 decreased from 46 +/- 4 to 36 +/- 5 torr (6.1 +/- 0.5 to 4.8 +/- 0.7 kPa; p < .01) in normal lungs and from 48 +/- 5 to 36 +/- 5 (6.4 +/- 0.7 to 4.8 +/- 0.7 kPa; p < .01). Meanwhile, tidal volume fraction decreased from 0.48 +/- 0.07 to 0.35 +/- 0.05 (p < .01) and from 0.56 +/- 0.07 to 0.40 +/- 0.07 (p < .01) in normal and injured lungs, respectively. Intrinsic PEEP of the new tube slightly increased, but there were no significant differences in comparison with the conventional tube. CONCLUSION Compared with the conventional endotracheal tube, the new double-lumen, two-stage endotracheal tube reduced Paco2 by decreasing anatomical deadspace in rabbits with normal and injured lungs under pressure control ventilation, thus enhancing ventilatory efficiency and reducing ventilator-induced injury.
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