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Models of Experimental Hypertension
Published in John H. McNeill, Measurement of Cardiovascular Function, 2019
Salah D. Kivlighn, Gloria J. Zingaro, Robert A. Gabel, Theodore P. Broten, Peter K.S. Siegl
The Milan hypertensive rat stain (MHS) and the normotensive control stain (MNS) were selectively derived from an outbred colony of Wistar origin.54 The Milan strains descended from only two pairs in the founding generation and are now in their 70th generation, of which 61 were brother by sister matings, the others 1st or 2nd cousin matings.55 This high state of inbreeding has produced two strains (hypertensive and normotensive) of animals that are genetically very similar. The genetic similarity has been confirmed. In a study of 370 microsatellite DNA probes, only 18% proved to be polymorphic and, among these loci, only one in the MNS was identified as heterozygotic.55 At weaning, the systolic blood pressure of the MHS (~100 mm Hg) is only slightly higher than that in the MNS (~90 mm Hg). A significant difference in blood pressure is usually seen beginning around 30 days of age, which continues to diverge until reaching a constant state at around 50 to 55 days of age. At this stage, blood pressure in the MHS is approximately 170 mm Hg, and in the MNS it is approximately 130 mm Hg.55 Heart rate is consistently lower in the MHS than the MNS at all ages.
Graft-Versus-Leukemia Effect of Allogeneic Bone Marrow Transplantation: Clinical and Experimental Aspects of Late Leukemia Relapse
Published in Thomas H. M. Stewart, E. Frederick Wheelock, Cellular Immune Mechanisms and Tumor Dormancy, 2017
Robert L. Truitt, Mary M. Horowitz, Ayse A. Atasoylu, William R. Drobyski, Bryon D. Johnson, Ann V. LeFever
Successful outcome of allogeneic BMT is associated with complete and stable engraftment of donor cells (complete chimerism). Although a relationship between incomplete or mixed chimerism (coexistence of donor and recipient cells post-transplant) and higher leukemia relapse rates has been suggested, mixed chimerism does not necessarily signify imminent relapse.68,69 Mixed lymphoid chimerism has become a more frequent occurrence with the increased use of T-cell-depletion as GVHD prophylaxis. It has been estimated to occur in 5-15% of T-replete bone marrow transplants, but may occur in up to 50% depending on the techniques used and whether lymphoid, erythroid or myeloid cells are evaluated.68,69 Using sensitive molecular techniques involving PCR amplification of microsatellite DNA (dinucleotide repeat sequences unique to the donor or recipient), Lawler et al.70 detected mixed chimerism in 18 of 32 allogeneic BMT patients (56%). Conventional cytogenetic analysis was possible in 17 patients, and mixed chimerism was detected in only three (18%). T-cell depletion was associated with a higher incidence of mixed chimerism (>80%) as compared to unmanipulated BM (44%). The overall level of recipient cells in patients who relapsed post-BMT was higher than in those who exhibited stable mixed chimerism. These authors concluded that while mixed chimerism was not indicative of a poor prognosis per se, sudden increases in the proportions of recipient cells may be a prelude to relapse.
DNA TECHNIQUES FOR THE AUTHENTICATION OF CHINESE MEDICINAL MATERIALS
Published in Kevin Chan, Henry Lee, The Way Forward for Chinese Medicine, 2001
Pang-Chui Shaw, Fai-Ngor Ngan, Paul Pui-Hay But, Jun Wang
Modifications have been made to simplify the methods of detection (Heath et al. 1993) and isolation of the flanking sequences (Thomas and Scott 1993; Rowe et al. 1994; Refseth et al. 1997). Recently, a new system named Random Amplified Hybridization Microsatellites (RAHM) (Cifarelli et al. 1995), Random-amplified Microsatellites Polymorphisms (RAMPO) (Richardson et al. 1995), or Random- amplified Microsatellites (RAMS) (Ender et al. 1996) that combines microsatellite DNA detection and RAPD amplification has been developed. This method detects second-level amplification products that are useful as molecular markers. RAPD or PCR using microsatellite primers is performed and the products are resolved on an agarose gel. A microsatellite-complementary oligonucleotide is used as a probe to hybridize the gel. Fragments with microsatellite loci will give a signal that may differentiate different species. More informative molecular markers are exploited to discriminate between intra- and inter-specific Dioscorea species by using mono-, tri- and tetra-nucleotides repeat probe (Ramser et al. 1997). The results are highly reproducible as the minor RAPD bands could also be detected by the method. RAMPO seems more reliable than RAPD in the studies of genetic relatedness as the size and intensity of two bands have to be identical for co-migration to be detectable. It reduces the risk of misinterpretation of co-migrating bands as homologs (Rieseberg 1996). Additional information can be obtained by reprobing the blot with more than five different probes without obvious loss in pattern quality (Ramser et al. 1997). This demonstrates the robustness of the method.
Multiple genetic analyses for Chinese Hunan Han population via 46 A-STRs
Published in Annals of Human Biology, 2022
Yunying Zhang, Yating Fang, Man Chen, Ming Zhao, Hui Xu, Congying Zhao, Jiangwei Lan, Bofeng Zhu
Short tandem repeats (STRs), also known as microsatellite DNA or simple sequence repeats, are the common kind of length polymorphisms, typically consisting of 2–6 bp tandem repeat units, which are widely found in eukaryotic genomes. Ever since their discovery in the early 1980s, STRs have gradually caught researchers’ eyes in many fields due to a great many noticeable advantages, such as high polymorphism, high heterozygosity, easy standardisation, and so on. Intensive studies (Ellegren 2004; Butler 2006) were conducted to reveal genetic and genomic information of STRs, which provided robust evidence to indicate that STRs were highly polymorphic for parentage testing and individual identification in forensic practice. What’s more, the Combined DNA Index System (CODIS) program supported by the Federal Bureau of Investigation, containing original 13 core loci (Budowle et al. 1998) and seven newly expanded loci (Butler and Hill 2012; Hares 2015), generalised and facilitated forensic applications of STR markers greatly. Nowadays, the aforementioned STR loci are commonly included in various commercial kits for forensic applications and do help resolve most routine cases. However, the discrimination powers of CODIS-based STR kits are sometimes inadequate in terms of complicated kinship analyses and cases with STR mutations. It has been proven that non-CODIS STRs could deal with complicated cases for biological relationship more effectively in some situations (Tsai et al. 2013), which implied that non-CODIS loci should be complementary to CODIS STRs to strengthen complex case-solving capability.
Mixed chimerism after allogeneic hematopoietic stem cell transplantation for severe aplastic anemia
Published in Hematology, 2021
Yuling Zhang, Yumiao Li, Liangliang Wu, Ming Zhou, Caixia Wang, Wenjian Mo, Xiaowei Chen, Shilin Xu, Ruiqing Zhou, Shunqing Wang, Yuping Zhang
Chimerism evaluation was performed monthly in the first 3 months, every 3 months between 3 months and 1 year, and every 6 months after 1 year from allo-HSCT using bone marrow or peripheral blood mononuclear cell. If a decrease in the PB cell count was detected during the follow-up, chimerism evaluation was then performed at any time. When the sex was different between the patient and the donor, fluorescence in situ hybridization and microsatellite DNA fingerprinting (also known as short tandem repeat) were used to detect chimerism. When the sex was the same, only microsatellite DNA fingerprinting was used for detection. DC was defined as >95% of donor cells, MC as 5-95% of recipient cells, and GF was defined as <5% of donor cells detected at any time following HSCT. The level of MC was classified based on the percentage of residual host cells (RHCs) in the PBs (level 1, <10% RHCs; level 2, 10-25% RHCs; level 3, >25% RHCs). Cytopenia was defined as fluctuating blood count and no recovery following treatment (specifically, neutrophil count <0.5 × 109, granulocyte stimulating factor treatment ineffective for 2 weeks, platelet count <20 × 109, infusion and other treatments ineffective for 2 weeks, hemoglobin concentration <60 g/l and no increase in the infusion and other treatments for 2 weeks). Finally, according to the percentage of donor-recipient chimerism and the presence or absence of cytopenia, patients with AA were divided into the following four groups: Group 1, DC; group 2, MC without cytopenia; group 3, MC with cytopenia; group 4, SGF.
Forensic genetic polymorphisms and population structure of the Guizhou Bouyei people based on 19 X-STR loci
Published in Annals of Human Biology, 2019
Zheng Ren, Jianxin Guo, Guanglin He, Han Zhang, Xing Zou, Hongling Zhang, Qiyan Wang, Jingyan Ji, Meiqing Yang, Jing Zhang, Ziqian Zhang, Yilizhati Nabijiang, Jiang Huang, Chuan-Chao Wang
Over the past few decades, the Short Tandem Repeat (STR, also named Microsatellite DNA) has been widely used in molecular anthropology and forensic studies. It has become one of the most efficient and powerful type of markers for exploring genetic polymorphisms, population structure and forensic characterisation (Kishida et al. 1997; Desmarais et al. 1998). The X-chromosome STR (X-STR), with its unique pattern of inheritance, has been used in complex kinship identification and forensic deficiency cases (Diegoli 2015), as well as population genetic analyses. The newly available commerce kit for genotyping X-STRs is the AGCU X19 X-STRs amplification kit (AGCU ScienTech Inc., Wuxi, Jiangsu, China), which can co-amplify and genotype 19 X-STRs belonging to seven linkage groups (Yang et al. 2016).