Qualitative and quantitative prediction of food allergen epitopes based on machine learning combined with in vitro experimental validation.

An allergen epitope is a part of molecules that can specifically bind to immunoglobulin E (IgE), causing an allergic reactions. To predict protein epitopes and their binding ability to IgE, quantitative structure-activity relationship (QSAR) models were established using four algorithms combined with the selected chemical descriptors. The model predicted the binding capabilities of the epitopes to IgE with the R2 and root mean squared error (RMSE) as 0.7494 and 0.2375, respectively. The model's performance was validated using an enzyme-linked immunosorbent assay (ELISA). The results showed that the established QSAR model could efficiently and accurately predict the allergic reaction of food protein epitopes. The prediction results of the model and the experimental results were consistent, with a Pearson correlation coefficient of 0.8956. The results from both the QSAR model and in vitro experiments indicated that amino acid sequence 116-130 was a novel IgE-binding epitope of ß-LG.

Pan-cancer analysis identifies NT5E as a novel prognostic biomarker on cancer-associated fibroblasts associated with unique tumor microenvironment.

Background: Ecto-5'-nucleotidase (NT5E) encodes the cluster of differentiation 73 (CD73), whose overexpression contributes to the formation of immunosuppressive tumor microenvironment and is related to exacerbated prognosis, increased risk of metastasis and resistance to immunotherapy of various tumors. However, the prognostic significance of NT5E in pan-cancer is obscure so far. Methods: We explored the expression level of NT5E in cancers and adjacent tissues and revealed the relationship between the NT5E expression level and clinical outcomes in pan-cancer by utilizing the UCSC Xena database. Then, correlation analyses were performed to evaluate the relationship between NT5E expression and immune infiltration level via EPIC, MCP-counter and CIBERSORT methods, and the enrichment analysis were employed to identify NT5E-interacting molecules and functional pathways. Furthermore, we conducted single-cell analysis to explore the potential role of NT5E on single-cell level based on the CancerSEA database. Meanwhile, gene set enrichment analysis (GSEA) in single-cell level was also conducted in TISCH database and single-cell signature explorer was utilized to evaluate the epithelial-mesenchymal transition (EMT) level in each cell type. Results: The expression level of NT5E was aberrant in almost all cancer types, and was correlated with worse prognosis in several cancers. Notably, NT5E overexpression was related to worse overall survival (OS) in pancreatic adenocarcinoma (PAAD), head and neck squamous cell carcinoma (HNSC), mesothelioma (MESO), stomach adenocarcinoma (STAD), uveal melanoma (UVM) and cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) (p < 0.01). NT5E-related immune microenvironment analysis revealed that NT5E is associated positively with the degree of infiltration of cancer-associated fibroblasts (CAFs) and endothelial cells in most cancers. Enrichment analysis of cellular component (CC) demonstrated the critical part of NT5E played in cell-substrate junction, cell-substrate adherens junction, focal adhesion and external side of plasma membrane. Finally, single-cell analysis of NT5E illuminated that EMT function of CAFs was elevated in basal cell carcinoma (BCC), skin cutaneous melanoma (SKCM), HNSC and PAAD. Conclusion: NT5E could serve as a potential prognostic biomarker for cancers. The potential mechanism may be related to the upregulated EMT function of CAFs, which provides novel inspiration for immunotherapy by targeting CAFs with high NT5E expression.

Worldwide productivity and research trend of publications concerning glioma-associated macrophage/microglia: A bibliometric study.

Glioma-associated macrophage/microglia (GAM) represents a key player in shaping a unique glioma ecosystem to facilitate tumor progression and therapeutic resistance. Numerous studies have been published concerning GAM, but no relevant bibliometric study has been performed yet. Our bibliometric study aimed to comprehensively summarize and analyze the global scientific output, research hotspots, and trendy topics of publications on GAM over time. Data on publications on GAM were collected using the Web of Science (WoS). The search date was 16 January 2022, and the publications were collected from 2002 to 2021. Totally, 1,224 articles and reviews were incorporated and analyzed in the current study. It showed that the annual publications concerning GAM kept increasing over the past 20 years. The United States had the largest number of publications and total citations. Holland, Kettenmann, and Gutmann were the top three authors in terms of citation frequency. Neuro-oncology represented the most influential journal in GAM studies, with the highest H-index, total citations, and publication numbers. The paper published by Hambardzumyan in 2016 had the highest local citations. Additionally, the analysis of keywords implied that "prognosis," "tumor microenvironment," and "immunotherapy" might become research hotspots. Furthermore, trendy topics in GAM studies suggested that "immune infiltration," "immune microenvironment," "bioinformatics," "prognosis," and "immunotherapy" deserved additional attention. In conclusion, this bibliometric study comprehensively analyzed the publication trend of GAM studies for the past 20 years, in which the research hotspots and trendy topics were also uncovered. This information offered scholars critical references for conducting in-depth studies on GAM in the future.

NT5E upregulation in head and neck squamous cell carcinoma: A novel biomarker on cancer-associated fibroblasts for predicting immunosuppressive tumor microenvironment.

Despite tremendous progress made in the diagnosis and managements, head and neck squamous cell carcinoma (HNSC) remains a global medical dilemma with dismal clinical prognosis and high mortality. Gene NT5E encodes the ecto-5'-nucleotidase (CD73), which facilitates the formation of immunosuppressive tumor microenvironment (TME) permissive for tumor progression in various malignancies. Nevertheless, the cell subsets NT5E expressed on and the potential function of NT5E in the TME of HNSC remain virgin lands in HNSC. In this study, we comprehensively performed integrated prognostic analysis and elucidated that NT5E was an independent prognostic indicator for HNSC, for which a high NT5E level predicted poor overall survival (OS), disease-specific survival (DSS) and progression-free interval (PFI) in HNSC patients (p<0.05). Enrichment analyses revealed the close correlation between NT5E and ECM remodeling, and the latent function of NT5E may involve in epithelial-to-mesenchymal transition (EMT) and metastasis during HNSC progression. HNSC-related immune infiltration analysis and single-cell type analysis demonstrated that NT5E expression was significantly positively associated with cancer-associated fibroblasts (CAFs) in HNSC (p<0.01). NT5E-related TME analysis revealed that NT5E-high group are characterized by low neoantigen loads (NAL, p<0.001) and tumor mutation burden (TMB, p<0.01), indicating high-NT5E-expression HNSC patients may be recalcitrant to immunotherapy. In-situ multicolor immunofluorescence staining was later conducted and the results further verified our findings. Taken together, NT5E could be a novel biomarker in HNSC. Predominantly expressed on CAFs, the upregulation of NT5E might predict an immunosuppressive TME for HNSC patients who may benefit little from immunotherapy. Targeting CAFs with high NT5E expression might be a novel therapeutic strategy for HNSC patients.

Prognostic Biomarker KIF18A and Its Correlations With Immune Infiltrates and Mitosis in Glioma.

Background: Glioma is globally recognised as one of the most frequently occurring primary malignant brain tumours, making the identification of glioma biomarkers critically significant. The protein KIF18A (Kinesin Family Member 18A) is a member of the kinesin superfamily of microtubule-associated molecular motors and has been shown to participate in cell cycle and mitotic metaphase and anaphase. This is the first investigation into the expression of KIF18A and its prognostic value, potential biological functions, and effects on the immune system and mitosis in glioma patients. Methods: Gene expression and clinicopathological analysis, enrichment analysis, and immune infiltration analysis were based on data obtained from The Cancer Genome Atlas (TCGA), with additional bioinformatics analyses performed. Statistical analysis was conducted in R software. Clinical samples were used to evaluate the expression of KIF18A via immunohistochemical staining. In addition, the expression level of KIF18A was validated on U87 cell line. Results: Our results highlighted that KIF18A plays a key role as an independent prognostic factor in patients with glioma. KIF18A was highly expressed in glioma tissues, and KIF18A expression was associated with age, World Health Organization grade, isocitrate dehydrogenase (IDH) status, 1p/19q codeletion, primary therapy outcome, and overall survival (OS). Enrichment analysis revealed that KIF18A is closely correlated with the cell cycle and mitosis. Single sample gene set enrichment analysis (ssGSEA) analysis revealed that KIF18A expression was related to the immune microenvironment. The increased expression of KIF18A in glioma was verified in clinical samples and U87 cell line. Conclusion: The identification of KIF18A as a new biomarker for glioma could help elucidate how changes in the glioma cell and immune microenvironment promote glioma malignancy. With further analysis, KIF18A may serve as an independent prognostic indicator for human glioma.

KIF5A upregulation in hepatocellular carcinoma: A novel prognostic biomarker associated with unique tumor microenvironment status.

Liver hepatocellular carcinoma (LIHC) is one of the most common liver malignancies with high mortality and morbidity. Thus, it is crucial to identify potential biomarker that is capable of accurately predicting the prognosis and therapeutic response of LIHC. Kinesin family member 5A (KIF5A) is a microtubule-based motor protein involved in the transport of macromolecules such as organelle proteins in cells. Recent studies have illustrated that the high expression of KIF5A was related to poor prognosis of solid tumors, including bladder cancer, prostate cancer, and breast cancer. However, little is currently known concerning the clinical significance of KIF5A expression in LIHC. Herein, by adopting multi-omics bioinformatics analysis, we comprehensively uncovered the potential function and the predictive value of KIF5A in stratifying clinical features among patients with LIHC, for which a high KIF5A level predicted an unfavorable clinical outcome. Results from KIF5A-related network and enrichment analyses illustrated that KIF5A might involve in microtubule-based process, antigen processing and presentation of exogenous peptide antigen via MHC class II. Furthermore, immune infiltration and immune function analyses revealed upregulated KIF5A could predict a unique tumor microenvironment with more CD8+T cells and a higher level of anti-tumor immune response. Evidence provided by immunohistochemistry staining (IHC) further validated our findings at the protein level. Taken together, KIF5A might serve as a novel prognostic biomarker for predicting immunotherapy response and could be a potential target for anti-cancer strategies for LIHC.

Surface defects induced charge imbalance for boosting charge separation and solar-driven photocatalytic hydrogen evolution.

Low charge separation efficiency of semiconductor materials is the main obstacle for high-performance photocatalyst. Herein, we report surface defects engineered uniform mesoporous TiO2 nanospheres (DMTNSs) through surfactant-mediated self-assembly solvothermal approach combined with hydrogenation strategy to promote charge separation. The surface defects induced charge imbalance result in the formation of built-in field, which can promote photogenerated charge separation efficiently and be confirmed by experimental and density functional theory (DFT) calculations. Under AM 1.5G irradiation, the photocatalytic hydrogen evolution of DMTNSs is ~3.34 mmol h-1 g-1, almost 3.5 times higher than that of pristine non-defective TiO2 nanospheres (0.97 mmol h-1 g-1), due to the engineered surface defects narrowing the bandgap (~3.01 eV) and inducing charge imbalance to boost spatial charge separation and extend visible-light response. The defect induced charge imbalance strategy opens a new valuable perspective for fabricating other high-efficient oxide photocatalysts.

Does Prior Cancer Have an Influence on the Survival Outcomes of Patients with Localized Pancreatic Neuroendocrine Tumors? / 中国医学科学杂志(英文版)

Objective To investigate the impact of prior non-pancreatic cancer on the survival outcomes of patients with localized pancreatic neuroendocrine tumors (PanNETs). Methods We reviewed the Surveillance, Epidemiology, and End Results database and selected patients with localized PanNETs diagnosed between 1973 and 2015. We divided the patients into two groups according to the presence or absence of prior non-pancreatic malignancy. Before and after propensity score matching, we compared the clinicopathological characteristics and studied the overall survival and cancer-specific survival. Results A total of 357 (12.9%) of 2778 patients with localized PanNETs had prior cancer. A total of 1211 cases with only a localized PanNET and 133 cases with a localized PanNET and prior cancer had complete data and met the inclusion criteria of the current study. Patients with prior cancer were associated with advanced age (>65 years, 57.9% prior cancer

Using a Nomogram to Preoperatively Predict Distant Metastasis of Pancreatic Neuroendocrine Tumor in Elderly Patients / 中国医学科学杂志(英文版)

Objective To establish a nomogram for predicting the distant metastasis risk of pancreatic neuroendocrine tumors (pNETs) in elderly patients. Methods We extracted data of patients with diagnosis of pNETs at age ≥65 years old between 1973 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database. All eligible patients were divided randomly into a training cohort and validation cohort. Uni- and multivariate logistic regression analyses were performed on the training cohort to identify independent factors for distant metastasis. A nomogram was developed based on the independent risk factors using rms packages of R software, and was validated internally by the training cohort and externally by the validation cohort using C-index and calibration curves. Results A total of 411 elderly patients were identified, of which 260 were assigned to training cohort and 151 to validation cohort. Univariate and multivariate logistic regression analyses indicated the tumor site (body/tail of pancreas: odds ratio [

A Rapid, Sensitive, Low-Cost Assay for Detecting Hydrogenotrophic Methanogens in Anaerobic Digesters Using Loop-Mediated Isothermal Amplification.

Understanding how the presence, absence, and abundance of different microbial genera supply specific metabolic functions for anaerobic digestion (AD) and how these impact on gas production is critical for a long-term understanding and optimization of the AD process. The strictly anaerobic methanogenic archaea are essential for methane production within AD microbial communities. Methanogens are a phylogenetically diverse group that can be classified into three metabolically distinct lineages based on the substrates they use to produce methane. While process optimization based on physicochemical parameters is well established in AD, measurements that could allow manipulation of the underlying microbial community are seldom used as they tend to be non-specific, expensive, or time-consuming, or a combination of all three. Loop-mediated isothermal amplification (LAMP) assays combine a simple, rapid, low-cost detection technique with high sensitivity and specificity. Here, we describe the optimization of LAMP assays for the detection of four different genera of hydrogenotrophic methanogens: Methanoculleus, Methanothermobacter, Methanococcus, and Methanobrevibacter spp. By targeting archaeal elongation factor 2 (aEF2), these LAMP assays provide a rapid, low-cost, presence/absence indication of hydrogenotrophic methanogens that could be used as a real-time measure of process conditions. The assays were shown to be sensitive to 1 pg of DNA from most tested methanogen species, providing a route to a quantitative measure through simple serial dilution of samples. The LAMP assays described here offer a simple, fast, and affordable method for the specific detection of four different genera of hydrogenotrophic methanogens. Our results indicate that this approach could be developed into a quantitative measure that could provide rapid, low-cost insight into the functioning and optimization of AD and related systems.

Dinuclear zinc synergistic catalytic asymmetric phospha-Michael/Michael cascade reaction: synthesis of 1,2,3-trisubstituted indanes bearing phosphoryl groups.

A new dinuclear zinc synergistic catalytic asymmetric phospha-Michael/Michael cascade reaction of o-dienones and dialkyl phosphates is reported. This method has been proven to be general and efficient for the formation of a range of chiral 1,2,3-trisubstituted indane compounds containing phosphorus groups in good yields (up to 92%) with excellent stereoselectivities (up to >99% ee and up to >99 : 1 dr). The relative configuration of the product was identified as having a trans,trans substitution pattern via two-dimensional (2D) nuclear Overhauser effect spectroscopy 1H-1H NMR experiments. A possible mechanism was proposed.

Enhancement of microbial density and methane production in advanced anaerobic digestion of secondary sewage sludge by continuous removal of ammonia.

Ammonia inhibition mitigation in anaerobic digestion of high solids content of thermally hydrolysed secondary sewage sludge by the NH4+ affinitive clinoptilolite and a strong acid type ion-exchange resin S957 was investigated. Continuous NH4+-N removal was achieved through ion-exchanging at both temperatures with average removals of 50 and 70% for the clinoptilolite and resin dosed reactors, respectively. Approximate 0.2-0.5unit of pH reduction was also observed in the dosed reactors. The synergy of NH4+-N removal and pH reduction exponentially decreased free NH3 concentration, from 600 to 90mg/L at 43°C, which mitigated ammonia inhibition and improved methane yields by approximately 54%. Microbial community profiling suggested that facilitated by ammonia removal, the improvement in methane production was mainly achieved through the doubling in bacterial density and a 6-fold increase in population of the Methanosarcinaceae family, which in turn improved the degradation of residual volatile fatty acids, proteins and carbohydrates.

[The therapeutic mechanisms of sirolimus treatment for ischemic-type biliary lesions after liver transplantation].

OBJECTIVE: To investigate the pathogenesis of ischemic-type biliary lesions (ITBLs) in post-liver transplant patients and the possible therapeutic mechanisms of sirolimus. METHODS: The clinic data of 32 post-liver transplant patients with ITBLs from May 2004 to December 2010 was analyzed. There were including 25 male and 7 female patients with a median age of 46 years (ranging from 19 to 61 years). Patients were divided into those who received sirolimus (sirolimus group) and those who did not (control group). The expression of IL-2, FoxP3, and IL-10 in the portal area, liver function indexes, and bile duct injury score were assessed pre-ITBL, when ITBLs were identified, and after 6 months of sirolimus treatment. RESULTS: Compared with pre-ITBL optical density (OD) values, there was a significantly increase in IL-2 OD(0.138 ± 0.050 in control group and 0.141 ± 0.052 in sirolimus group), but not FoxP3 and IL-10 OD in both groups at the time ITBLs were diagnosed. After 6 months of treatment, the IL-2, FoxP3, and IL-10 OD values in the control group were not different from those when ITBLs were diagnosed. There was a significant reduction in post-therapy IL-2 OD(0.107 ± 0.043, t = 2.087, P = 0.044), and a significant elevation in FoxP3(0.213 ± 0.039) and IL-10 OD(0.187 ± 0.048) in sirolimus group as compared with those when ITBLs were diagnosed(t = -3.822 and -4.350, both P < 0.01). There was a significant increase in serum levels of ALT, AST, total bilirubin, γ-glutamyl transpeptidase and ALP at the time ITBLs were diagnosed compared with pre-ITBL levels in both groups. After 6 months of treatment, the above indexes had not changed in the control group, but significantly improved in the sirolimus group, and the bile duct injury score in the sirolimus group had significantly decreased(4.4 ± 2.4, Z = -2.568, P = 0.010). The 1-year and 3-year graft survival rates in the control group were 6/13 and 5/13, respectively, and 17/19 and 13/19, respectively, in the sirolimus group (χ(2) = 7.166, P = 0.007; χ(2) = 5.398, P = 0.020, respectively). CONCLUSIONS: Sirolimus can downregulate IL-2 expression and upregulate FoxP3 and IL-10 expression, thereby stimulating FoxP3+ Treg cells, suppressing immunopathological damage, and promoting epithelial repair in bile ducts.

Metaldehyde removal from aqueous solution by adsorption and ion exchange mechanisms onto activated carbon and polymeric sorbents.

Metaldehyde removal from aqueous solution was evaluated using granular activated carbon (GAC), a non-functionalised hyper-cross-linked polymer Macronet (MN200) and an ion-exchange resin (S957) with sulfonic and phosphonic functional groups. Equilibrium experimental data were successfully described by Freundlich isotherm models. The maximum adsorption capacity of S957 (7.5 g metaldehyde/g S957) exceeded those of MN200 and GAC. Thermodynamic studies showed that sorption of metaldehyde onto all sorbents is endothermic and processes are controlled by entropic rather than enthalpic changes. Kinetic experiments demonstrated that experimental data for MN200 and GAC obey pseudo-second order models with rates limited by particle diffusion. Comparatively, S957 was shown to obey a pseudo-first order model with a rate-limiting step of metaldehyde diffusion through the solid/liquid interface. Results obtained suggest that metaldehyde adsorption onto MN200 and GAC are driven by hydrophobic interactions and hydrogen bonding, as leaching tendencies were high since no degradation of metaldehyde occurred. Conversely, adsorption of metaldehyde onto S957 occurs via ion-exchange processes, where sulfonic and phosphonic functionalities degrade adsorbed metaldehyde molecules and failure to detect metaldehyde in leaching studies for S957 supports this theory. Consequently, the high adsorption capacity and absence of leaching indicate S957 is promising for metaldehyde removal from source water.

The therapeutic mechanisms of sirolimus treatment for ischemic-type biliary lesions after liver transplantation / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the pathogenesis of ischemic-type biliary lesions (ITBLs) in post-liver transplant patients and the possible therapeutic mechanisms of sirolimus.</p><p><b>METHODS</b>The clinic data of 32 post-liver transplant patients with ITBLs from May 2004 to December 2010 was analyzed. There were including 25 male and 7 female patients with a median age of 46 years (ranging from 19 to 61 years). Patients were divided into those who received sirolimus (sirolimus group) and those who did not (control group). The expression of IL-2, FoxP3, and IL-10 in the portal area, liver function indexes, and bile duct injury score were assessed pre-ITBL, when ITBLs were identified, and after 6 months of sirolimus treatment.</p><p><b>RESULTS</b>Compared with pre-ITBL optical density (OD) values, there was a significantly increase in IL-2 OD(0.138 ± 0.050 in control group and 0.141 ± 0.052 in sirolimus group), but not FoxP3 and IL-10 OD in both groups at the time ITBLs were diagnosed. After 6 months of treatment, the IL-2, FoxP3, and IL-10 OD values in the control group were not different from those when ITBLs were diagnosed. There was a significant reduction in post-therapy IL-2 OD(0.107 ± 0.043, t = 2.087, P = 0.044), and a significant elevation in FoxP3(0.213 ± 0.039) and IL-10 OD(0.187 ± 0.048) in sirolimus group as compared with those when ITBLs were diagnosed(t = -3.822 and -4.350, both P < 0.01). There was a significant increase in serum levels of ALT, AST, total bilirubin, γ-glutamyl transpeptidase and ALP at the time ITBLs were diagnosed compared with pre-ITBL levels in both groups. After 6 months of treatment, the above indexes had not changed in the control group, but significantly improved in the sirolimus group, and the bile duct injury score in the sirolimus group had significantly decreased(4.4 ± 2.4, Z = -2.568, P = 0.010). The 1-year and 3-year graft survival rates in the control group were 6/13 and 5/13, respectively, and 17/19 and 13/19, respectively, in the sirolimus group (χ(2) = 7.166, P = 0.007; χ(2) = 5.398, P = 0.020, respectively).</p><p><b>CONCLUSIONS</b>Sirolimus can downregulate IL-2 expression and upregulate FoxP3 and IL-10 expression, thereby stimulating FoxP3+ Treg cells, suppressing immunopathological damage, and promoting epithelial repair in bile ducts.</p>

[The comparison of the vasoactive effects of dopamine on isolated rabbit pulmonary and systemic arteries after incubation with lipopolysaccharide].

OBJECTIVE: To compare the vasoactive effects of dopamine (DOPA) of different concentrations on isolated rabbit pulmonary and systemic arteries after incubation with lipopolysaccharide (LPS). METHODS: Six white male rabbits were used. Thirty-six pulmonary arterial rings and 36 systemic arterial rings were prepared. The 36 pulmonary arterial rings were divided into six groups to determine the effect of different concentrations of DOPA (4x10(-5) , 8x10(-5), 16x10(-5) micromol/L) on the tension of the normal pulmonary artery (PN-DOPA4, PN-DOPA8, PN-DOPA16 groups, respectively), and the tension of the pulmonary artery rings after being incubated with LPS (PL-DOPA4, PL-DOPA8, PL-DOPA16 groups, respectively). The 36 systemic arterial rings were also divided into six groups as the pulmonary arterial rings, including normal groups (SN-DOPA4, SN-DOPA8 , SN-DOPA16) and LPS groups (SL-DOPA4, SL-DOPA8 , SL-DOPA16). RESULTS: (1) DOPA relaxed the arterial rings in PN-DOPA4 and SN-DOPA4 groups, while it produced contraction in PN-DOPA8, PN-DOPA16, SN-DOPA8 and SN-DOPA16 groups, and the contraction was more marked with the increase in concentration of DOPA. (2) After preincubation with LPS, the relaxation property of DOPA in PL-DOPA4 and SL-DOPA4 groups was observed to be reversed to contraction [(22.60+/-6.68)% vs. -(2.25+/-0.58)%, (3.80+/-0.52)% vs. -(3.65+/-0.75)%, P<0.05 and P<0.01]; the contraction response of DOPA in PL-DOPA8 group decreased compared with PN-DOPA8 group by (14.52+/-0.59)% (P<0.05), while increased by (25.90+/-1.75)% in SL-DOPA8 group compared with SN-DOPA8 group (P<0.05), and no response was observed in PL-DOPA16 and SL-DOPA16 groups. (3)After preincubation with LPS, changes in pulmonary arterial tension (PL/PN) in DOPA4 group were more obvious than those in systemic arterial tension (SL/SN, -10.90+/-5.06 vs. -1.00+/-0.24, P<0.05), while the SL/SN in DOPA8 group were more obvious (1.80+/-0.35 vs. 0.48+/-0.17, P<0.01). CONCLUSION: DOPA in low concentrations had the function of relaxation on the pulmonary arterial and systemic arterial rings. After the arterial rings are preincubated with LPS, the relaxation response of DOPA of low concentrations is changed to be vaso-contraction, and the changes in pulmonary arterial rings are most marked. DOPA of different concentrations all produce contraction effect on LPS-preincubated arterial rings.

[The effects of dopamine on pulmonary artery pressure in dogs with endotoxic shock].

OBJECTIVE: To evaluate the values of dopamine in treating endotoxic shock by observing the changes in the pulmonary artery pressure (PAP) during the treatment. METHODS: Twenty healthy dogs were randomly divided into four groups with 5 in each group. Endotoxic model was reproduced by injecting lipopolysaccharides (LPS) 1 mg/kg intravenously. Two hours later, normal saline (NS) 5 ml/h was intravenously given in model group, or dopamine 5, 10, 20 microg*kg(-1)*min(-1) was given in D5 group, D10 group, D20 group intravenously. Femoral artery pressure, femoral vein pressure and PAP were measured, and mean arterial pressure (MAP) and mean pulmonary artery pressure (MPAP) were recorded at 0, 5, 10, 30, 60, 120 minutes after infusion of NS or dopamine. RESULTS: Compared with the model group, all different concentrations of dopamine could elevate MAP, MPAP (P<0.05 or P<0.01). Compared with D5 group, the percentage of elevation of MAP of D10 group and D20 group was greater, and the percentage of elevation of MPAP of D20 group was greater than that in D5 group and D10 group (P<0.05 or P<0.01). The ratio of MAP/MPAP in each dopamine group was higher than that of model group, and the increase was more marked in the groups of higher concentrations (all P<0.05). CONCLUSION: MAP of endotoxic dog lowered obviously, while there was little change in PAP. After infusion of dopamine intravenously, both MAP and PAP are elevated. The increase in resistance of pulmonary microcirculation is the main reason for the elevation of PAP.