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Kaviani R, Chou FY, He CB, Marquez V. A95 ASSESSMENT OF BIRTH COHORT SCREENING OF CHRONIC HEPATITIS C IN COLORECTAL CANCER SCREENING PATIENTS IN BRITISH COLUMBIA. J Can Assoc Gastroenterol 2023. [PMCID: PMC9991092 DOI: 10.1093/jcag/gwac036.095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/09/2023] Open
Abstract
Background Birth cohort screening of chronic hepatitis C (CHC) is recommended in British Columbia since 2018 for baby boomers born between 1945 to 1964, with an estimated provincial prevalence of 2.31%. Though there remained a gap in care following anti-hepatitis C positivity, resulting in reflexive ribonucleic acid (RNA) testing provincially. Dual screening of CHC in patients referred to colorectal (CRC) screening programs can provide an opportunity to link patients with healthcare professionals to ensure appropriate follow-up. Purpose We aimed to assess the uptake of CHC screening amongst CRC screening patients after the release of British Columbia’s birth cohort guidelines, both pre and post-COVID-19 pandemic. Method A retrospective review of patients referred to a CRC screening program in Vancouver from October 1st to December 31st, 2019, and December 1st – 31st, 2021, was performed. Collected data included demographics, liver disease history, and co-infection rates with hepatitis B (HBV) or human immunodeficiency virus (HIV). Dates of first-time hepatitis C antibody, RNA and viral load testing were gathered. Descriptive statistics were used to identify the proportion of screening and prevalence of CHC. Result(s) A total of 553 patients were referred for colonoscopy to the CRC screening program, of whom 458 (82.8%) patients were born between 1945 to 1964, and 273 (n=49%) were female. Among the 250 (45.2%) patients screened for CHC, 4 (0.72%) had positive anti-hepatitis C, all of whom were baby boomers. In 2019, 44% (n=183) of patients were screened for CHC; 78.7% (n=144) were screened before colonoscopy referral. In 2020, 48.6% (n=67) of patients were screened for CHC; 100% of cases were screened before colonoscopy referral. Conclusion(s) Birth cohort screening of CHC is underutilized in British Columbia. Dual screening of CHC at the time of referral to CRC screening provides a practical approach to linking patients to healthcare. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared
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Affiliation(s)
| | | | | | - V Marquez
- Gastroenterology, University of British Columbia, Vancouver, Canada
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He CB, Wang J, Mao YZ, Lao XM, Li SP. [Comparison of the efficacy of irreversible electroporation and conversional resection for locally advanced pancreatic cancer]. Zhonghua Wai Ke Za Zhi 2022; 60:948-954. [PMID: 36207984 DOI: 10.3760/cma.j.cn112139-20220415-00168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Objective: To compare the short-term and long-term prognosis of irreversible electroporation(IRE) and conversional resection for locally advanced pancreatic cancer(LAPC). Methods: The clinical and pathological data of 98 LAPC patients who underwent IRE or conversional resection at the Department of Pancreatobiliary Surgery,Sun Yat-sen University Cancer Center from August 2015 to December 2020 were retrospectively collected and analyzed.The study comprised of 53 males and 45 females, with age(M(IQR)) of 57.5(13.5)years old(range:20 to 87 years old). Fifty-three patients received IRE treatment(IRE group) and 45 patients received surgical resection(resection group). The differences of clinical and pathological data between both groups were not significant(all P<0.05). The Mann-Whitney U test was used for quantitative data and the χ2 test was used for categorical data.Survival was analyzed using Kaplan-Meier method and compared using Log-rank test. Results: The operation time and intraoperative blood loss were 5.0(2.4)hours and 50(100) ml in the IRE group,respectively,which were significantly less than those of resection group(7.0(3.3)hours and 400(200)ml,both P<0.05).The hospital stay and hospitalization cost were 9.0(3.0)days and 79 154 (83 738) yuan in the IRE group,respectively,which were also significantly less than those in the resection group(16.0(8.5)days and 109 557(37 795)yuan,both P<0.05).The complication rate of IRE group was significantly lower than that of the resection group(18.8% vs. 55.6%,χ2=14.270,P<0.01).The median overall survival(OS) time of IRE group was 28.9 months(95%CI:23.2 to 34.6 months),with the 1-,2-,and 3-year OS rates of 91.6%,61.7%,and 24.6%,respectively.The median survival of OS of resection group was 27.1 months(95%CI:20.9 to 33.3 months),with the 1-,2-,and 3-year OS rates of 81.8%,53.9%,and 30.3%,respectively.There was no significant difference in OS between the two groups(χ2=0.900,P=0.760).The median progression free survival(PFS) time of IRE group was 18.0 months(95%CI:14.7 to 21.3 months),with the 1-,2-,and 3-year PFS rates of 68.3%,29.7%,and 9.9%,respectively.The median survival of PFS of resection group was 11.1 months(95%CI:6.1 to 16.2 months),with the 1-,2-,and 3-year PFS rates of 45.2%,21.9%,and 14.6%,respectively.There was no significant difference in PFS between the two groups(χ2=1.850,P=0.170). Conclusion: IRE can achieve similar survival for LAPC and may has less complications compared to those with conversion resection.
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Affiliation(s)
- C B He
- Department of Pancreatobiliary Surgery,State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Sun Yat-sen University Cancer Center,Guangzhou 510060,China
| | - J Wang
- Department of Pancreatobiliary Surgery,State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Sun Yat-sen University Cancer Center,Guangzhou 510060,China
| | - Y Z Mao
- Department of Pancreatobiliary Surgery,State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Sun Yat-sen University Cancer Center,Guangzhou 510060,China
| | - X M Lao
- Department of Pancreatobiliary Surgery,State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Sun Yat-sen University Cancer Center,Guangzhou 510060,China
| | - S P Li
- Department of Pancreatobiliary Surgery,State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Sun Yat-sen University Cancer Center,Guangzhou 510060,China
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Li SP, He CB, Wang J, Mao YZ, Lao XM, Cui BK, Lin XJ. [Combining intraoperative ultrasound-guided irreversible electroporation with chemotherapy for treating locally advanced pancreatic cancer: a clinical report of 64 cases]. Zhonghua Wai Ke Za Zhi 2020; 58:787-792. [PMID: 32993267 DOI: 10.3760/cma.j.cn112139-20200331-00270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To examine the safety and clinical efficacy of ultrasound-guided irreversible electroporation (IRE) using the open surgery approach, after induction chemotherapy, in the treatment of locally advanced pancreatic cancer (LAPC) . Methods: The data of 64 LAPC patients who underwent ultrasound-guided IRE using the open surgery approach after induction chemotherapy at Department of Pancreatobiliary Surgery, Sun Yat-sen University Cancer Center from August 2015 to March 2019 were retrospectively analyzed. The study comprised of 30 males and 34 females, with median age of 58.5 years old (range: 34 to 87 years old) , were included in this study.The tumor was located in the pancreatic head and body/tail in 30 and 34 patients, respectively.The largest recorded tumor size was 6.1 cm (≤4.0 cm: n=35; >4.0 cm: n=29) .To create an electric field around the tumor, Two to six probes were parallelly inserted into each patient's tumor, based on the size of the tumor, at a distance of 2 cm apart through the transverse mesocolon in a caudal-to-cranial direction.According to the numerical sequence of patients undergoing ultrasound-guided IRE, the first 15 cases and following 49 patients were categorized as the primary and secondary treatment group, respectively.T text or χ(2) test was analyzed to the data between two groups.The study endpoints were overall survival (OS) and progression free survival (PFS) , which were investigated using Kaplan-Meier method, and their differences were compared using log-rank test. Results: The overall length of hospital stay was (8.9±2.7) days (range: 5 to 20 days) . Four patients were lost to follow-up.The study follow-up rate was 93.8%, with a median follow-up time of 29.3 months (range: 13.5 to 55.7 months) .The median OS and PFS of the entire cohort was 24.6 months (95% CI: 22.0 to 27.3 months) and 12.0 months (95%CI: 8.8 to 15.2 months) , respectively.One month after IRE, abdominal pain was significantly relieved in 95.3% of the patients (t=-28.55, P<0.01) .The rate of complications in the entire cohort was 20.3% and all were classified as grade B.Of them, pancreatic fistula, incisional infection, and upper gastrointestinal hemorrhage were observed in 7, 4, and 2 cases, respectively.The rate of complications for patients in the primary and secondary treatment groups were significantly different (10/15 vs. 6.1%) , respectively (χ(2)=26.01, P<0.01) .Further, two deaths were observed after IRE in the primary treatment group, while none was observed in the secondary treatment group. Conclusions: Ultrasound-guided IRE using the open surgery approach after induction chemotherapy is found to be safe and effective in treating patients with LAPC.However, these findings should be validated in prospective randomized trials before wide clinical application.
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Affiliation(s)
- S P Li
- Department of Pancreatobiliary Surgery, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - C B He
- Department of Pancreatobiliary Surgery, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - J Wang
- Department of Pancreatobiliary Surgery, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Y Z Mao
- Department of Pancreatobiliary Surgery, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - X M Lao
- Department of Pancreatobiliary Surgery, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - B K Cui
- Department of Pancreatobiliary Surgery, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - X J Lin
- Department of Pancreatobiliary Surgery, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
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He CB, Li Q, Ye YC, Zhao XL, Tu CC, Zeng Y. [Effects of clopidogrel resistence and CYP2C19 genotype on the clinical prognosis of patients with acute coronary syndrome undergoing percutaneous coronary intervention]. Zhonghua Xin Xue Guan Bing Za Zhi 2020; 48:765-771. [PMID: 32957760 DOI: 10.3760/cma.j.cn112148-20191228-00773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the effects of clopidogrel resistence and CYP2C19 genotype on the clinical prognosis of acute coronary syndrome(ACS) patients undergoing percutaneous coronary intervention(PCI). Methods: This study was a retrospective cohort study. ACS patients who underwent PCI in Beijing Anzhen Hospital from October 2015 to January 2017 were recruited. The inhibition rate of adenosine diphosphate(ADP) was monitored by thromboelastography. All of these patients were divided into clopidogrel resistance and non-resistance group according to the monitoring results. CYP2C19 genotype was detected by TaqMan probe-based real-time quantitative PCR. Patients were divided into slow, medium and fast metabolic group, according to the CYP2C19 genotype. After 12 months of follow-up, the end points included all-cause death, cardiac death, angina, myocardial infarction, stent thrombosis, ischemic stroke and hemorrhage were collected. Combined thrombotic events were defined as a composite of angina, myocardial infarction, stent thrombosis and ischemic stroke. The differences of the incidence of clinical events between groups were compared. Cox regression was used to analyze the effects of clopidogrel resistance and CYP2C19 genotype on the combined thrombotic events, cardiac death and hemorrhage. Results: A total of 1 696 patients were included, and the age was (59.4±9.6) years, with 1 280(75.5%) males. There were 471 cases(27.8%) in clopidogrel resistance group, and 1 225 cases(72.2%) in clopidogrel non-resistance group. There were 218 patients(12.9%) were in slow metabolic group, 668(39.4%) in medium metabolic group, and 810 (47.8%) in fast metabolic group. The median follow-up time was 13.3 months, and 131 cases were lost to follow-up, with a loss follow-up rate of 7.7%. Compared with the clopidogrel non-resistance group, the clopidogrel resistance group had a higher incidence of myocardial infarction(7.6%(36/471) vs. 5.1%(62/1 225), P=0.041), a lower incidence of hemorrhage (13.2%(62/471) vs. 17.9%(219/1 225), P=0.020) and minor hemorrhage(11.5%(54/471) vs. 15.8% (194/1 225), P=0.022). There were no statistically significant difference in all-cause death, cardiac death, angina, stent thrombosis, ischemic stroke and severe bleeding between clopidogrel resistance and non-resistance group(all P>0.05). There was no statistically significant difference in the incidence of endpoint events among different CYP2C19 genotypes (all P>0.05). Cox regression analysis showed that clopidogrel resistance was an independent factor of combined thrombotic events (OR=2.334, 95%CI 1.215-4.443, P=0.016) and bleeding events (OR=0.481, 95%CI 0.174-0.901, P=0.023). While CYP2C19 genotype was not independent factor for combined thrombotic events, cardiac death and hemorrhage (all P>0.05). Conclusion: For ACS patients after PCI, clopidogrel resistance can increase the risk of combined thrombotic events, but also reduce the risk of bleeding; while CYP2C19 genotype is not an independent factor for clinical prognosis.
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Affiliation(s)
- C B He
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Q Li
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Y C Ye
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - X L Zhao
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - C C Tu
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Y Zeng
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
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He CB, Pan KL, Chang MB. Catalytic oxidation of trichloroethylene from gas streams by perovskite-type catalysts. Environ Sci Pollut Res Int 2018; 25:11584-11594. [PMID: 29429106 DOI: 10.1007/s11356-018-1440-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 01/30/2018] [Indexed: 06/08/2023]
Abstract
Three perovskite-type catalysts including LaMnO3, La0.8Ce0.2MnO3, and La0.8Ce0.2 Mn0.8Ni0.2O3 are prepared using citric acid sol-gel method and evaluated as catalyst for the oxidation of trichloroethylene (TCE) in air with temperature ranging from 100 to 600 °C. The physicochemical properties of three perovskite-type catalysts were characterized by SEM, EDS, XRD, BET, and XPS to investigate the relationship with catalytic activities. The results show that the removal efficiency of TCE achieved with La0.8Ce0.2Mn0.8Ni0.2O3 (the best one) reaches 100% at 400 °C and the mineralization efficiency reaches 100% at 600 °C. The enhanced activity can be attributed to the addition of Ce and Ni which increases the surface areas, active oxygen species, and the redox ability of the Mn4+/Mn3+ ratio on the catalyst surface. As La0.8Ce0.2Mn0.8Ni0.2O3 is applied for TCE oxidation, the main intermediate chlorinated byproduct detected is tetrachloroethylene (C2Cl4) which is generated by the reaction of TCE and chlorine (Cl2). The activation energy for the TCE oxidation with La0.8Ce0.2Mn0.8Ni0.2O3 catalyst is 51 kJ/mol using kinetic models of power-law type.
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Affiliation(s)
- Cheng Bin He
- Graduate Institute of Environmental Engineering, National Central University, No.300, Jhongda Road, Jhongli District, Taoyuan City, 32001, Taiwan
| | - Kuan Lun Pan
- Graduate Institute of Environmental Engineering, National Central University, No.300, Jhongda Road, Jhongli District, Taoyuan City, 32001, Taiwan
| | - Moo Been Chang
- Graduate Institute of Environmental Engineering, National Central University, No.300, Jhongda Road, Jhongli District, Taoyuan City, 32001, Taiwan.
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Gao XG, Pu HS, He CB, Bao XB, Liu WD. Genetic variations in the UTR of genes related to molting in Eriocheir sinensis. Genet Mol Res 2015; 14:12472-8. [PMID: 26505397 DOI: 10.4238/2015.october.16.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Crab grows by periodic molting, which is controlled by molt-inhibiting hormone (MIH) and ecdysteroids. Untranslated regions (UTRs) play crucial roles in the posttranscriptional regulation of gene expression. In this study, using crab collected from Changjiang (Yangtze), Huanghe (Yellow), Liaohe, and Yalujiang rivers, 33 haplotypes of the 3ꞌ-UTR of ecdysteroid-regulated protein (ERP) gene were identified, of which 14 haplotypes were observed in more than one individual. One hundred and forty clones of haplotype h2 (41.5%) were observed in samples from all the 4 rivers. Three haplotypes were observed to be insertions. For the whole crab sample, we found a positive Tajima's D value and a negative Fu's Fs test (Tajima's D value = 0.98726; Fu's Fs test = -27.382), although the P values were not significant (P > 0.10). The network profile of these 33 haplotypes presented a single core pattern with h2 as the core. In this study, we found that the UTR of ERP gene had a considerably high genetic polymorphism among crab from regions south to north of China. Furthermore, we observed a relatively high genetic divergence among different haplotypes, which would suggest a high diversity of the crab gene pool.
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Affiliation(s)
- X G Gao
- Key Lab of Marine Fishery Molecular Biology of Liaoning Province, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - H S Pu
- School of Food Science Engineering, Dalian Polytechnic University, Dalian, China
| | - C B He
- Key Lab of Marine Fishery Molecular Biology of Liaoning Province, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - X B Bao
- Key Lab of Marine Fishery Molecular Biology of Liaoning Province, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - W D Liu
- Key Lab of Marine Fishery Molecular Biology of Liaoning Province, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
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Bao XB, He CB, Fu CD, Wang B, Zhao XM, Gao XG, Liu WD. A C-type lectin fold gene from Japanese scallop Mizuhopecten yessoensis, involved with immunity and metamorphosis. Genet Mol Res 2015; 14:2253-67. [PMID: 25867372 DOI: 10.4238/2015.march.27.11] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
C-type lectins are a superfamily of Ca(2+)-dependent carbohydrate-recognition proteins that are well known for their participation in pathogen recognition and clearance. In this study, a putative C-type lectin fold (MyCLF) gene was identified from the Japanese scallop Mizuhopecten yessoensis. The full-length of MyCLF was 645 bp, encoding a polypeptide of 167 amino acids. MyCLF carried a signal peptide of 20 amino acid residues, and a single carbohydrate recognition domain, having relatively high amino acid sequence conservation with C-type lectins reported for other bivalves. The expression of MyCLF mRNA transcripts in adult tissues, after bacterial challenge and during different developmental stages was determined using real-time quantitative RT-PCR. MyCLF was mainly distributed in the mantle, gill, and kidney. The expression of MyCLF clearly increased 3 h after Vibrio anguillarum challenge, and dropped to a minimum level after 9 h compared to the control group. During embryonic development, the expression level increased in the gastrulae, trochophore and early D-shaped larvae, decreased in D-shaped larvae, and then increased hundreds of times in metamorphosing larvae. The results suggested that MyCLF was involved in an immune response and it may play important roles during the metamorphosis phase of M. yessoensis.
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Affiliation(s)
- X B Bao
- Liaoning Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - C B He
- Liaoning Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - C D Fu
- Liaoning Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - B Wang
- Liaoning Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - X M Zhao
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
| | - X G Gao
- Liaoning Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - W D Liu
- Liaoning Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
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Gao XG, Han JB, Lu ZC, Zhang PJ, He CB. Sequence variation and gene duplication at the MHC DRB loci of the spotted seal Phoca largha. Genet Mol Res 2015; 14:2055-62. [PMID: 25867351 DOI: 10.4238/2015.march.20.15] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The major histocompatibility complex (MHC) is one of the most important genetic systems associated with resistance to infectious diseases in vertebrates. The spotted seal (Phoca largha) is one of the most endangered species in China. In this study, we present the first step in the molecular characterization of a DRB-like locus in the spotted seal by analyzing the nucleotide sequence of the polymorphic exon 2 segments, a 288-nucleotide sequence. By examining the segment from a group of 41 individuals, 28 alleles were identified. No deletion, insertion, or exceptional stop codon was detected, suggesting that these alleles could be functional in vivo. The nucleotide and amino acid sequences of the segment both showed a relatively high level of similarity (nucleotides 97%; amino acids 98%) to those of Meles meles and Zalophus californianus. The high level of spotted seal MHC-DRB polymorphism revealed in the present study has not been reported for the Phocidae and could be a consequence of the small spotted seal population adapting to the Bohai Sea, which probably has a relatively high level of pathogens.
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Affiliation(s)
- X G Gao
- Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - J B Han
- Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - Z C Lu
- Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - P J Zhang
- Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - C B He
- Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
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Li YF, Gao XG, Liu WD, Tian Y, Gao L, Li SL, He CB. Microsatellite markers derived from Japanese scallop (Mizuhopecten yessoensis) expressed sequence tags. Genet Mol Res 2014; 13:1989-92. [PMID: 24737424 DOI: 10.4238/2014.march.24.3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Japanese scallop (Mizuhopecten yessoensis) is a cold-water shellfish, and a species of economic importance in China. In this study, we developed and evaluated simple sequence repeat (SSR) markers from the expressed sequence tags (ESTs) of M. yessoensis. The characteristics of 12 EST-SSR loci were investigated in 30 individual scallops, and the result revealed that the number of alleles per locus ranged from 2-4, with an observed heterozygosity ranging from 0.0333-0.7692, and an expected heterozygosity ranging from 0.0333-0.6312. Only two loci were found to depart significantly from the Hardy-Weinberg equilibrium (P < 0.05). The result of our study suggested that these markers could be considered as potential markers for studying the population structure of M. yessoensis and its intraspecific variation.
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Affiliation(s)
- Y F Li
- Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - X G Gao
- Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - W D Liu
- Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - Y Tian
- College of Fisheries and Life Science, Dalian Ocean University, Dalian, China
| | - L Gao
- Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - S L Li
- Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - C B He
- Key Laboratory of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
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Tan BH, Hussain H, Lin TT, Chua YC, Leong YW, Tjiu WW, Wong PK, He CB. Stable dispersions of hybrid nanoparticles induced by stereocomplexation between enantiomeric poly(lactide) star polymers. Langmuir 2011; 27:10538-10547. [PMID: 21761846 DOI: 10.1021/la202110w] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report the formation and characterization of stable dispersions of hybrid nanoparticles in solution formed via stereocomplexation of enantiomeric poly(lactide) hybrid star polymers. The hybrid starlike polymers, having polyhedral oligomeric silsesquioxane (POSS) nanocages as the core and either poly(L-lactide) (PLLA) or poly(D-lactide) (PDLA) as the arms, are synthesized via ring-opening polymerization of lactide using octafunctional POSS as the macroinitiator. In the solid state, differential scanning calorimetry and wide-angle X-ray scattering measurements confirmed the formation of the stereocomplex in the mixture of POSS-star-PLLA and POSS-star-PDLA (50:50, wt %). In a solution of the same mixture in tetrahydrofuran (THF), sterocomplexation leads to formation of hybrid nanaoparticles. Detailed accounts of the nanoparticle formation and influence of aging and concentration have been presented. It was observed that at low concentration the stereocomplexed nanaoparticles remain stable over 45 days and are not sensitive to dilution, suggesting the formation of a stable hybrid nanoparticle dispersion in solution. In contrast, the aggregates of the individual POSS-star-PLLA or POSS-star-PDLA in THF, formed via weak solvophobic interactions, tended to disintegrate into smaller aggregates on dilution. Exploiting the PLLA-PDLA stereocomplexation with an appropriate molecular design can be a versatile route to develop stable organic/inorganic hybrid nanoparticle dispersions.
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Affiliation(s)
- B H Tan
- Institute of Materials Research and Engineering (IMRE), A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602
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Hussain H, Tan BH, Seah GL, Liu Y, He CB, Davis TP. Micelle formation and gelation of (PEG-P(MA-POSS)) amphiphilic block copolymers via associative hydrophobic effects. Langmuir 2010; 26:11763-11773. [PMID: 20536258 DOI: 10.1021/la101686q] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A series of well-defined amphiphilic di- and triblock copolymers have been synthesized, using atom transfer radical polymerization, with poly(ethylene glycol) (PEG) and poly(methacrylisobutyl polyhedral oligomeric silsesquioxane) P(MA-POSS) as the hydrophilic and hydrophobic blocks, respectively. The detailed self-assembly behavior of the amphiphilic macromolecules in aqueous media was studied using both static and dynamic light scattering (SLS and DLS) techniques. The evolution of block copolymer micelle formation in THF/water mixture (20/80 v/v) was monitored as the THF evaporated from the solvent mixture. Initially the block copolymer chains existed as unimers in solution, followed by the formation of smaller aggregates (R(h) < 2 nm) after 30 min, eventually growing in size to reach an equilibrium size when all the THF evaporated within 24 h. The micelles formed by the block copolymers were found to be kinetically unstable (not frozen); i.e., they tended to revert to individual copolymer chains on dilution. The hydrodynamic radii, R(h), of the micelles varied with the degree of polymerization (DP) of the hydrophobic P(MA-POSS); for example, for PEG(5K)-b-P(MA-POSS), an increase from R(h) approximately 13.3 +/- 1.1 nm to R(h) approximately 17.5 +/- 1.4 nm was observed with a nominal change in the DP of P(MA-POSS) from 4 to 6. The micelles formed by the triblock copolymers (P(MA-POSS)-b-PEG(10K)-b-P(MA-POSS)) were comparable in size to the diblock copolymer micelles; e.g., R(h) approximately 14.0 +/- 1.3 nm was found for P(MA-POSS)(4)-b-PEG(10K)-b-P(MA-POSS)(4). The micellar structures created by the triblocks in aqueous media were "flowerlike", where the PEG middle block adopted a loop conformation in the micelle corona. In addition to micelles, larger aggregates formed by P(MA-POSS)-b-PEG(10K)-b-P(MA-POSS) were also detected in solution. The larger aggregates may suggest a contribution from some PEG blocks adopting an extended conformation with one end dangling in solution, causing gelation at higher copolymer concentrations via intermicellar interactions. The P(MA-POSS)(4)-b-PEG(10K)-b- P(MA-POSS)(4) formed a gel in water at approximately 8.8 wt % copolymer concentration. No gel formation by diblock copolymers was observed; however, the addition of a small amount of triblock copolymer to an aqueous solution of diblock copolymer results in gel formation. Finally, rheological behavior of the obtained gels was also investigated.
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Affiliation(s)
- H Hussain
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 3 Research Link, Singapore 117602.
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Tan BH, Hussain H, Liu Y, He CB, Davis TP. Synthesis and self-assembly of brush-type poly[poly(ethylene glycol)methyl ether methacrylate]-block-poly(pentafluorostyrene) amphiphilic diblock copolymers in aqueous solution. Langmuir 2010; 26:2361-2368. [PMID: 19785395 DOI: 10.1021/la902816b] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Well-defined fluorinated brush-like amphiphilic diblock copolymers of poly[poly(ethylene glycol)methyl ether methacrylate] (P(PEGMA)) and poly(pentafluorostyrene) (PPFS) have been successfully synthesized via atom transfer radical polymerization (ATRP). The self-assembly behavior of these polymers in aqueous solutions was studied using (1)H NMR, fluorescence spectrometry, static and dynamic light scattering and transmission electron microscopy techniques. The micellar structure comprised of PPFS as the core and brush-like (hydrophobic main chain and hydrophilic branches) polymers as the coronas. The hydrodynamic radius (R(h)) of the micelles in aqueous solution was in the nanometer range, independent of the polymer concentration, consistent with a closed association model. Diblock copolymers with a longer P(PEGMA) block formed micelles with smaller R(h) and lower aggregation numbers consistent with an improved solubilization of the core. The micelles possessed a thick hydration layer as verified by the ratio of the radius of gyration, R(g) to the hydrodynamic radius, R(h). The aggregation number and ratio of R(g) to R(h) were observed to increase with temperature (20-50 degrees C), while the R(h) of the micelle decreased slightly over the same temperature range. An increase in temperature induced the brush-like PEG segments in the corona to dehydrate and shrink while forming micelles with larger aggregation numbers.
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Affiliation(s)
- B H Tan
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 3 Research Link, Singapore 117602.
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Hussain H, Tan BH, Gudipati CS, He CB, Liu Y, Davis TP. Micelle formation of amphiphilic polystyrene-b-poly(N-vinylpyrrolidone) diblock copolymer in methanol and water-methanol binary mixtures. Langmuir 2009; 25:5557-5564. [PMID: 19371048 DOI: 10.1021/la8042389] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The micelle formation by the amphiphilic polystyrene-block-poly(N-vinylpyrrolidone) (PS48-b-PNVP99) copolymer is investigated in methanol and water-methanol binary mixtures of various compositions using 1H NMR, fluorescence spectroscopy, static/dynamic light scattering (SLS/DLS), and transmission electron microscopy (TEM). Critical micelle concentrations (cmc) are determined by employing fluorescence spectroscopy and DLS measurements. The cmc of the PS48-b-PNVP99 block copolymer increases with increasing methanol content in the water-methanol binary mixtures, suggesting that methanol is a better solvent for the PS48-b-PNVP99 block copolymer than water-methanol mixtures or pure water. The amphiphilic PS48-b-PNVP99 diblock copolymer forms spherical micelles of Rh approximately 16 nm in pure methanol solution as revealed by DLS measurements. In contrast, significantly larger micelles having higher aggregation numbers are formed in water-methanol binary mixtures. Temperature dependent data reveal an increase in aggregation number and radius of gyration (Rg) concomitantly with temperature (10-40 degrees C). In contrast, the overall size (Rh) of the micelles remains almost constant over the same temperature range. An explanation is tendered that PNVP coronas dehydrate/desolvate at higher temperatures counteracting the increase in micelle size (Rh) caused by increased aggregation numbers (Nagg).
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Affiliation(s)
- H Hussain
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 3 Research Link, Singapore 117602
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Wang ZL, He CB. [Bronchogenic carcinoma complicated with pneumonoconiosis in coal miners (author's transl)]. Zhonghua Zhong Liu Za Zhi 1981; 3:184-7. [PMID: 7338145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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