1.Spaceflight-induced variation on biological traits and effective components of Cassia obtusifolia.
Ren-jun MAO ; Zhi-hong QI ; Rui-lian HAN ; Feng-hua LIU ; Yan LIU ; Zong-suo LIANG
China Journal of Chinese Materia Medica 2015;40(13):2571-2575
The dry seeds of Cassia obtusifolia were carried by the "ShenZhou 8" satellite and sowed after landing. Based on our pri- or study on SP1, the characteristics of plants growth, physiological index and content of effective components were examined. The results showed that the QC10, QC29 strains matured 5 d earlier compared with control. The plant height, across diameter and ground diameter of QC10, QC29, QC46 strains was superior to the control at whole growth period. The branch number increased ranging from 4 to 11 and the number of pods reached 321, 313,281, respectively, which was dramatically higher than the control (246). The yield of QC10, QC29, QC46 strains increased noticeably from 31.4 to 63.2 g. The 1000-seed-weight of QC10, QC29, QC46 strains was 25.86, 25.88, 24.06 g, while the control was 23.69 g. Compared to the control, the mass fraction of chlorophyll was enhanced 1.098, 1.016, 0.297 mg. There was no significant difference in aurantio-obtusin and chrysophanol content of seeds. Through two years research, three high-yield mutant strains were obtained. This study indicates that spaceflight-induced mutants could provide new germplasm for C. obtusifolia breeding and offers the theoretical basis for further utilization of spaceflight-induced mutation to breed high-quality C. obtusifolia strains.
Cassia
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chemistry
;
genetics
;
growth & development
;
Mutation
;
Space Flight
2.Effect of different heat treatment on mechanical properties and microstructure of laser welding CoCr-NiCr dissimilar alloys.
Rui-ying LIANG ; Chang-yi LI ; Ya-jing HAN ; Xin HU ; Lian-yun ZHANG
Chinese Journal of Stomatology 2008;43(11):689-692
OBJECTIVETo evaluate the effect of heat treatment and porcelain-fused-to-metal (PFM) processing on mechanical properties and microstructure of laser welding CoCr-NiCr dissimilar alloys.
METHODSSamples of CoCr-NiCr dissimilar alloys with 0.5 mm thickness were laser-welded single-side under the setting parameters of 280 V, 10 ms pulse duration. After being welded, samples were randomly assigned to three groups, 10 each. Group1 and 2 received heat treatment and PFM processing, respectively. Group 3 was control group without any treatment. Tensile strength, microstructure and element distribution of samples in the three groups were tested and observed using tensile test, metallographic examinations, scanning electron microscope (SEM), and energy dispersive spectroscopy (EDS) analysis.
RESULTSAfter heat treatment and PFM processing, tensile strength of the samples were (537.15 +/- 43.91) MPa and (534.58 +/- 48.47) MPa respectively, and elongation rates in Group 1 and 2 were (7.65 +/- 0.73)% and (7.40 +/- 0.45)%. Ductile structure can be found on tensile fracture surface of samples and it was more obvious in heat treatment group than in PFM group. The results of EDS analysis indicated that certain CoCr alloy diffused towards fusion zone and NiCr side after heat treatment and PFM processing. Compared with PFM processing group, the diffusion in the heat treatment group was more obvious.
CONCLUSIONSHeat treatment and PFM processing can improve the mechanical properties and microstructure of welded CoCr-NiCr dissimilar alloy to a certain degree. The improvements are more obvious with heat treatment than with porcelain treatment.
Dental Alloys ; chemistry ; Dental Stress Analysis ; Hot Temperature ; Lasers ; Materials Testing ; Tensile Strength ; Welding
3.High-risk human papillomavirus genotype distribution and attribution to cervical cancer and precancerous lesions in a rural Chinese population.
Xue Lian ZHAO ; Shang Ying HU ; Qian ZHANG ; Li DONG ; Rui Mei FENG ; Ross HAN ; Fang Hui ZHAO
Journal of Gynecologic Oncology 2017;28(4):e30-
OBJECTIVE: To explore the genotype distribution of high-risk human papillomavirus (HR-HPV) and its attribution to different grades of cervical lesions in rural China, which will contribute to type-specific HPV screening tests and the development of new polyvalent HPV vaccines among the Chinese population. METHODS: One thousand two hundred ninety-two subjects were followed based on the Shanxi Province Cervical Cancer Screening Study I (SPOCCS-I), and screened by HPV DNA testing (hybrid capture® 2 [HC2]), liquid-based cytology (LBC), and if necessary, directed or random colposcopy-guided quadrant biopsies. HPV genotyping with linear inverse probe hybridization (SPF10-PCR-LiPA) was performed in HC2 positive specimens. Attribution of specific HR-HPV type to different grades of cervical lesions was estimated using a fractional contribution approach. RESULTS: After excluding incomplete data, 1,274 women were included in the final statistical analysis. Fifteen point two percent (194/1,274) of women were HR-HPV positive for any of 13 HR-HPV types (HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68) and the most common HR-HPV types were HPV16 (19.1%) and HPV52 (16.5%). The genotypes most frequently detected in HR-HPV-positive cervical intraepithelial neoplasia grade 1 (CIN1) were HPV52 (24.1%), HPV31 (20.7%), HPV16 (13.8%), HPV33 (13.8%), HPV39 (10.3%), and HPV56 (10.3%); in HR-HPV-positive cervical intraepithelial neoplasia grade 2 or worse (CIN2+): HPV16 (53.1%), HPV58 (15.6%), HPV33 (12.5%), HPV51 (9.4%), and HPV52 (6.3%). HPV52, 31, 16, 33, 39, and 56 together contributed to 89.7% of HR-HPV-positive CIN1, and HPV16, 33, 58, 51, and 52 together contributed to 87.5% of CIN2+. CONCLUSION: In summary, we found substantial differences in prevalence and attribution of CINs between different oncogenic HPV types in a rural Chinese population, especially for HPV16, 31, 33, 52, and 58. These differences may be relevant for both clinical management and the design of preventive strategies.
Asian Continental Ancestry Group*
;
Biopsy
;
Cervical Intraepithelial Neoplasia
;
China
;
Female
;
Genotype*
;
Human Papillomavirus DNA Tests
;
Humans*
;
Mass Screening
;
Papillomavirus Vaccines
;
Prevalence
;
Uterine Cervical Neoplasms*
4.Application and analysis of abdominal aortic branch malperfusion pattern in thoracic endovascular aortic repair for Stanford B aortic dissection
feng Xiao HAN ; Xi GUO ; zheng Tie LI ; rui Guang LIU ; jun Lian HUANG
Journal of Peking University(Health Sciences) 2017;49(6):996-1002
Objective:To evaluate the efficiency of thoracic endovascular aortic repair (TEVAR) in dealing with abdominal aortic branch malperfusion based on the analysis of aortic computed tomography angiography (CTA) images in pre-and post-TEVAR.Methods:Retrospective analysis from September 2015 to March 2016 in single institution to 32 patients,diagnosed as Stanford B aortic dissection with abdominal aortic branch malperfusion,CTA images in pre-and post-TEVAR were collected.Based on the aortic branch malperfusion pattern redefined by Nagamine,we identified and characterized branch malperfusion pattern for four abdominal aortic branches (celiac trunk,superior mesenteric artery,bilateral renal artery) in statistical analysis.Results:In the four abdominal aortic branches (total 128 branches),86 branches (67.2%) expressed with Class Ⅰ patterns,in which subtype Ⅰ-b presented with 0.8%,subtype Ⅰ-c with 5.5%;14 branches (10.9%) expressed with Class Ⅱ patterns,in which subtype Ⅱ-b-1 with 3.9%,subtype Ⅱ-b-2 with 3.1%;16 branches (12.5%) expressed with Class Ⅲ patterns,all with subtype Ⅲ-a,no subtype Ⅲ-b and Ⅲ-c presented.The remaining 12 branches were normal.The 100% successful rate of TEVAR obtained in 32 patients performed.The mean following-up was 4 months.Aortic CTA showed that among the 14 "high-risk" abdominal aortic branch malperfusion,13 (92.9%) with obvious branch malperfusion in post-TEVAR were observed to improve,and the remaining one branch malperfusion (7.1%) was observed to change from subtype Ⅰ-b to Ⅰ-c.Conclusion:Few ratios in abdominal aortic branches suffered with obvious malperfusion complicated by Stanford B aortic dissection.For branches with "high-risk" malperfusion pattern,optimal changes were observed in abdominal aortic branch without revascularization in post-TEVAR,as well other branches with non-" high-risk" pattern perfusion were mostly stable in post-TEVAR.It could be of profound benefit to extend branch malperfusion patterns redefined by Nagamine in clinical practice to assess aortic dissection and in further guide for revascularization or not.
5.Association of heart valve calcification with cardiovascular outcomes in patients on maintenance hemodialysis.
Zhi-Lian LI ; Chao-Sheng HE ; Yuan-Han CHEN ; Xin-Ling LIANG ; Wei DONG ; Rui-Zhao LI ; Si-Jia LI ; Li-Xia XU ; Zhong-Lin FENG ; Hua-Ban LIANG ; Li-Fen WANG ; Wei SHI
Journal of Southern Medical University 2016;36(7):941-946
OBJECTIVETo investigate the impact of heart valve calcification (HVC) on cardiovascular outcomes in patients on maintenance hemodialysis (MHD).
METHODSWe enrolled 302 Chinese patients on MHD between 2009 and 2011 including 99 with HVC identified by echocardiography screening. All the patients were followed up for 2 years and survival analysis was performed with all-cause mortality, cardiovascular mortality and new onset cardiovascular events as the endpoints. Cox regression analysis was used for analyzing the impact of heart valve calcification on the cardiovascular outcomes of the patients.
RESULTSThe mean age of the total patients was 58.2∓15.0 years when receiving the initial MHD, and 53.6% were male patients. The overall mortality, cardiovascular mortality and new on-set cardiovascular events in HVC and non-HVC groups were 30.3% vs 16.3%, 22.2% vs 6.9%, and 48.5% vs 25.6%, respectively (P<0.05). Kaplan-Meier survival analysis showed a significant difference in all-cause mortality (P=0.006), cardiovascular mortality (P<0.001) and new-onset cardiovascular events (P<0.001) between HVC and non-HVC groups. After adjustment, Cox regression analysis identified HVC as a risk factor for increased all-cause mortality (HR=1.88; 95%CI: 1.11-3.19), cardiovascular mortality (HR=3.47, 95%CI: 1.76-6.84) and cardiovascular events (HR=1.64, 95% CI: 1.09-2.47).
CONCLUSIONSHVC is an independent risk factor for increased cardiovascular mortality and new cardiovascular events in patients on MHD.
Adult ; Aged ; Calcinosis ; pathology ; Echocardiography ; Female ; Heart Valve Diseases ; mortality ; pathology ; Heart Valves ; pathology ; Humans ; Kaplan-Meier Estimate ; Male ; Middle Aged ; Renal Dialysis ; Risk Factors
6.Evaluation of immunization protection efficacy of plague subunit vaccine.
Qing-wen ZHANG ; Zhi-zhen QI ; You-quan XIN ; Yong-hai YANG ; Hai-lian WU ; Han-qing YANG ; Jian-ping FENG ; Xing JIN ; Bai-zhong CUI ; Tang WANG ; Ben-chuan WU ; Ye-feng QIU ; Wang WANG ; Zhao-biao GUO ; Zu-yun WANG ; Rui-fu YANG ; Hu WANG ; Xiao-yi WANG
Chinese Journal of Preventive Medicine 2009;43(9):785-788
OBJECTIVETo evaluate the protective efficacy of plague subunit vaccine, BALB/c mice, guinea pigs and rabbits were used in this study.
METHODSGroups of mice (10 per group), guinea pigs (14 per group) and rabbits (6 per group) were immunized with F1 + rV270 vaccine, EV76 vaccine and alum adjuvant by intramuscular route, respectively. Serum antibody titres of mice, guinea pigs and rabbits were determined by ELISA and the immunized animals were challenged with 10(6) CFU of Y. pestis strain 141 at the 8th week after the primary immunization.
RESULTSThe immunized mice, guinea pigs or rabbits with subunit vaccine developed anti-F1 IgG titre of 41 587.3 +/- 2.1, 11 543.7 +/- 2.1 or 522.4 +/- 22.4 and elicited statistical anti-F1 IgG titre difference among them (F = 17.58, P < 0.01). The immunized mice, guinea pigs or rabbits with subunit vaccine had anti-rV270 IgG titre of 15 748.7 +/- 1.6, 12.6 +/- 1.4 or 1648.0 +/- 5.0 and induced statistical anti-rV270 IgG titre difference among them (F value was 16.34, P < 0.01). There was significant anti-F1 IgG titre difference among mice, guinea pigs and rabbits immunized with EV76 vaccine that developed anti-F1 IgG titre of 913.4 +/- 4.5, 937.0 +/- 2.0 or 342.0 +/- 12.0 (F = 23.67, P < 0.01), whereas the immunized mice, guinea pigs and rabbits with EV76 vaccine developed anti-rV270 IgG titre of 12.0 +/- 1.0, 447.0 +/- 10.0, 40.0 +/- 11.0 and there was no anti-rV270 IgG titre difference between them (F = 2.20, P = 0.1314). The immunized mice with subunit vaccine developed significantly higher anti-F1 IgG titres than immunized guinea pigs and rabbits (q value was 30.57 and 19.04, respectively, P < 0.01), and there were no anti-F1 IgG titre differences between the immunized guinea pigs and rabbits (q = 0.04, P = 0.8485). The immunized mice with subunit vaccine developed significantly higher anti-rV270 IgG titres than immunized guinea pigs and rabbits (q value was 27.10 and 19.49, respectively, P < 0.01), and there were no anti-rV270 IgG titre differences between the immunized guinea pigs and rabbits with the subunit vaccine (q = 0.25, P = 0.6187). The immunized mice with EV76 elicited higher anti-F1 IgG titres than immunized guinea pigs and rabbits (q value was 40.67 and 29.10, respectively, P < 0.01), whereas there was no difference of F1 IgG titer between immunized guinea pigs and rabbits (q = 0.06, P = 0.8098). The immunized mice, guinea pigs and rabbits with subunit vaccine provided 100% (10/10), 86% (12/14) and 100% (5/5) protection against 10(6) CFU Y. pestis of challenge, respectively. The immunized mice, guinea pigs and rabbits with EV76 vaccine gave 100% (6/6), 93% (13/14) and 100% (6/6) protection against 10(6) CFU Y. pestis of challenge respectively.
CONCLUSIONBALB/c mice is the best small animal model for valuation of protective efficacy of plague subunit vaccine. The guinea pigs showed a high individual variation for this purpose. The rabbits can be used as an alternative model for evaluating plague subunit vaccine.
Animals ; Antibodies, Bacterial ; blood ; Dose-Response Relationship, Immunologic ; Female ; Guinea Pigs ; Immunization ; Immunoglobulin G ; blood ; Mice ; Mice, Inbred BALB C ; Models, Animal ; Plague ; prevention & control ; Plague Vaccine ; immunology ; Rabbits ; Vaccines, Subunit ; immunology
7.Systemic Inflammatory Biomarkers, Especially Fibrinogen to Albumin Ratio, Predict Prognosis in Patients with Pancreatic Cancer
Lin FANG ; Fei-Hu YAN ; Chao LIU ; Jing CHEN ; Dan WANG ; Chun-Hui ZHANG ; Chang-Jie LOU ; Jie LIAN ; Yang YAO ; Bo-Jun WANG ; Rui-Yang LI ; Shu-Ling HAN ; Yi-Bing BAI ; Jia-Ni YANG ; Zhi-Wei LI ; Yan-Qiao ZHANG
Cancer Research and Treatment 2021;53(1):131-139
Purpose:
Systemic inflammatory response is a critical factor that promotes the initiation and metastasis of malignancies including pancreatic cancer (PC). This study was designed to determine and compare the prognostic value of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), and fibrinogen-to-albumin ratio (FAR) in resectable PC and locally advanced or metastatic PC.
Materials and Methods:
Three hundred fifty-three patients with resectable PC and 807 patients with locally advan-ced or metastatic PC were recruited in this study. These patients were classified into a training set (n=758) and a validation set (n=402). Kaplan-Meier survival plots and Cox proportional hazards regression models were used to analyze prognosis.
Results:
Overall survival (OS) was significantly better for patients with resectable PC with low preoperative PLR (p=0.048) and MLR (p=0.027). Low FAR, MLR, NLR (p < 0.001), and PLR (p=0.003) were significantly associated with decreased risk of death for locally advanced or metastatic PC patients. FAR (hazard ratio [HR], 1.522; 95% confidential interval [CI], 1.261 to 1.837; p < 0.001) and MLR (HR, 1.248; 95% CI, 1.017 to 1.532; p=0.034) were independent prognostic factors for locally advanced or metastatic PC.
Conclusion
The prognostic roles of FAR, MLR, NLR, and PLR in resectable PC and locally advanced or metastatic PC were different. FAR showed the most prognostic power in locally advanced or metastatic PC. Low FAR was positively correlated with OS in locally advanced or metastatic PC, which could be used to predict the prognosis.
8.Gene mutation profiles and clinicopathological features of patients with non-small cell lung cancer harboring KRAS G12C mutation: a single-center retrospective study.
Lian Ying GUO ; Chan XIANG ; Rui Ying ZHAO ; Sheng Nan CHEN ; Sheng Ji MA ; Yu Chen HAN
Chinese Journal of Pathology 2023;52(2):117-123
Objective: To accurately screen non-small cell lung cancer (NSCLC) patients with KRAS G12C mutation and to evaluate their clinicopathological features, prognostic factors and current treatment status. Methods: A total of 19 410 NSCLC cases diagnosed at the Department of Pathology of Shanghai Chest Hospital, Shanghai, China from January 2018 to September 2021 were retrospectively reviewed, and the cases with KRAS gene mutation detected by next-generation sequencing were included. The clinicopathological and genetic mutation data of these cases were collected and analyzed. Results: A total of 1 633 (8.4%) NSCLC patients carried a KRAS gene mutation, among whom G12C was the most frequent (468 cases, 28.7%) mutant subtype. The mutation was more commonly found in males (414/468, 88.5%), patients with a history of smoking (308/468, 65.8%), and patients with a pathological type of invasive adenocarcinoma (231/468, 49.4%). The most common co-mutated genes in KRAS G12C mutant NSCLC were TP53 (52.4%, 245/468), STK11 (18.6%, 87/468) and ATM (13.2%, 62/468). The proportion of PD-L1 expression (≥1%) in KRAS G12C mutant NSCLC was significantly higher than that in patients without G12C mutation [64.3% (90/140) vs. 56.1% (193/344), P=0.014]. Immune checkpoint inhibitors (ICIs) treatment significantly prolonged progression-free survival (PFS) in NSCLC patients (10.0 months vs. 5.0 months, P=0.011). However, combination of chemotherapy and ICIs with anti-angiogenesis inhibitors or multi-target inhibitors did not significantly improve PFS in patients with KRAS G12C mutant NSCLC (P>0.05). Patients with KRAS G12C mutation NSCLC treated with ICIs and KRAS G12C patients with TP53 mutation had significantly longer median PFS than those with STK11 mutation (9.0 months vs. 4.3 months, P=0.012). Conclusions: Patients with KRAS G12C mutant NSCLC have relatively higher levels of PD-L1 expression and can benefit from ICIs treatment. The feasibility of chemotherapy, ICIs therapy and their combination needs further investigation.
Humans
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Male
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B7-H1 Antigen/genetics*
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Carcinoma, Non-Small-Cell Lung/pathology*
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China
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Lung Neoplasms/pathology*
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Mutation
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Proto-Oncogene Proteins p21(ras)/genetics*
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Retrospective Studies
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Female
9.Therapeutic effect and mechanism of non-polysaccharide fraction of Bletillae Rhizoma in treatment of gastric ulcer based on network pharmacology and animal experiment.
Jing-Xian FANG ; Lian ZHANG ; Jing LI ; Han-Rui ZHANG ; Dan LIU ; Jing NIE ; Xiao-Chuan YE
China Journal of Chinese Materia Medica 2023;48(16):4446-4458
The present study aimed to explore the therapeutic effect and mechanism of non-polysaccharide fraction of Bletillae Rhizoma in the treatment of gastric ulcer by network pharmacology and animal experiments. UPLC-Q-TOF-MS/MS was employed to chara-cterize the chemical components of non-polysaccharide fraction of Bletillae Rhizoma, and the common targets of Bletillae Rhizoma and gastric ulcer were screened out by network pharmacology. The "drug-component-target-disease" network was constructed. Protein-protein interaction(PPI) network was established by STRING. Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analyses were performed based on Matescape database to predict the therapeutic effect and mechanism of Bletillae Rhizoma. Finally, the gastric ulcer model was induced in mice by alcohol to verify the therapeutic effect and mechanism of non-polysaccharide fraction of Bletillae Rhizoma on gastric ulcer. Forty-seven chemical components were identified from non-polysaccharide fraction of Bletillae Rhizoma, among which gymnoside Ⅰ, gymnoside Ⅱ, militarine, bletilloside A, and shancigusin I might be the main active components of non-polysaccharide fraction of Bletillae Rhizoma against gastric ulcer. PPI network analysis revealed core targets such as albumin(ALB), serine/threonine kinase 1(AKT1), tumor necrosis factor(TNF), and epidermal growth factor receptor(EGFR). The KEGG enrichment analysis showed that non-polysaccharide fraction of Bletillae Rhizoma mainly exerted the therapeutic effect by regulating the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT) signaling pathway, mitogen-activated protein kinase(MAPK) signaling pathway, and Ras signaling pathway. The results of animal experiments showed that non-polysaccharide fraction of Bletillae Rhizoma could significantly improve alcohol-induced ulceration in mice to increase ulcer inhibition rate, decrease the levels of TNF-α, interleukin(IL)-1β, IL-6, vasoactive intestinal peptide(VIP), and thromboxane B2(TXB2), elevated the le-vels of IL-10, prostaglandin E2(PGE2), epidermal growth factor(EGF), and vascular endothelial growth factor(VEGF), down-re-gulate the protein levels of PI3K and AKT, and up-regulate the protein levels of p-PI3K and p-AKT. This study indicates that Bletillae Rhizoma may play a role in the treatment of gastric ulcer through multiple components, targets, and pathways and verifies partial prediction results of network pharmacology. The findings of this study provide a scientific and experimental basis for clinical application.
Animals
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Mice
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Stomach Ulcer/drug therapy*
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Proto-Oncogene Proteins c-akt
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Animal Experimentation
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Network Pharmacology
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Phosphatidylinositol 3-Kinases
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Tandem Mass Spectrometry
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Vascular Endothelial Growth Factor A
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Tumor Necrosis Factor-alpha
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Molecular Docking Simulation
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Drugs, Chinese Herbal/pharmacology*
10.Effect of convection enhanced delivery on the microstructure of brain extracellular space in aged rats.
Yu SONG ; Hong Bin HAN ; Jun YANG ; Ai Bo WANG ; Qing Yuan HE ; Yuan Yuan LI ; Guo Mei ZHAO ; Ya Juan GAO ; Rui WANG ; Yi Xing HAN ; Ai Lian LIU ; Qing Wei SONG
Journal of Peking University(Health Sciences) 2020;52(2):362-367
OBJECTIVE:
To compare the changes of extracellular space (ECS) structure and local drug distribution in adult brain and aged brain at different drug delivery rates in minimally invasive treatment of encephalopathy by convection enhanced delivery (CED) via ECS pathway.
METHODS:
Thirty-six SD male rats were divided into adult rats group (2-8 months, n=18) and aged rats group (18-24 months, n=18) according to the age of the month. According to the drug rates (0.1 μL/min, 0.2 μL/min, and 0.3 μL/min), they were randomly divided into 3 subgroups, 6 in each subgroup. Gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) with a concentration of 10 mmol/L were introduced into the caudate nucleus of each group of rats by stereotactic injection. Tracer-based magnetic resonance imaging (MRI) was used to dynamically monitor the diffusion and distribution images of the Gd-DTPA in the brain interstitial system (ISS). Using the self-developed MRI image measurement and analysis system software to process and analyze the obtained images, the diffusion coefficient, clearance rate, volume fraction, and half-life of each group of rats in the caudate nucleus ECS could be acquired. The effects and differences of drug clearance and ECS structural function in the brain of aged rats and adult rats were compared and analyzed at different drug delivery rates. Magnetic tracer DECS-mapping technique was used to observe the distribution and drainage of tracer in caudate nucleus.
RESULTS:
At the injection rate of 0.1 μL/min, the volume fraction in the aged rats was increased compared with that in the adult rats (18.20%±0.04% vs. 17.20%±0.03%, t=3.752, P=0.004), and the degree of tortuosity was decreased (1.63±0.04 vs. 1.78±0.09, t=-3.680, P=0.004), the drug clearance rate was decreased [(1.94±0.68) mm2/s vs. (3.25±0.43) mm2/s, t=-3.971, P=0.003], and the molecular diffusion in ECS was increased [(3.99±0.21)×10-4 mm2/s vs. (3.36±0.37)×10-4 mm2/s, t=3.663, P=0.004]. When the rate of injection increased to 0.2 μL/min, the drug clearance in ECS of the aged rats was slowed down [(2.53±0.45) mmol/L vs. (3.37±0.72) mmol/L, t=-1.828, P=0.021]. However, there were no significant differences in volume fraction, molecular diffusion in ECS and macroscopic drug metabolism parameters. When the rate of injection increased to 0.3 μL/min, the volume fraction in the aged rats was decreased (17.20%±0.03% vs. 18.20%±0.05%, t=-0.869, P=0.045), and the drug clearance rate in ECS was significantly accelerated [(4.04±0.76) mmol/L vs. (3.26±0.55) mmol/L, t=1.786, P=0.014], and there was no significant difference in tortuosity and the rate of molecular diffusion in the ECS.
CONCLUSION
The drug clearance and ECS structural parameters of brain ECS in aged brain with CED administration were changed at different rates, and it has the least effect on ECS in the aged brain at the injection rate of 0.2 μL/min. For the application of CED for the treatment of encephalopathy, we should consider the influence of factors such as age and injection rate, and provide reference for the development of individualized clinical treatment plan for minimally invasive treatment of encephalopathy via ECS pathway.
Animals
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Brain
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Convection
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Extracellular Space
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Gadolinium DTPA
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Magnetic Resonance Imaging
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Male
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Rats
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Rats, Sprague-Dawley