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201.
Gerbitz A Sukumar M Helm F Wilke A Friese C Fahrenwaldt C Lehmann FM Loddenkemper C Kammertoens T Mautner J Schmitt CA Blankenstein T Bornkamm GW 《PloS one》2012,7(3):e34552
To study mechanisms of T cell-mediated rejection of B cell lymphomas, we developed a murine lymphoma model wherein three potential rejection antigens, human c-MYC, chicken ovalbumin (OVA), and GFP are expressed. After transfer into wild-type mice 60-70% of systemically growing lymphomas expressing all three antigens were rejected; lymphomas expressing only human c-MYC protein were not rejected. OVA expressing lymphomas were infiltrated by T cells, showed MHC class I and II upregulation, and lost antigen expression, indicating immune escape. In contrast to wild-type recipients, 80-100% of STAT1-, IFN-γ-, or IFN-γ receptor-deficient recipients died of lymphoma, indicating that host IFN-γ signaling is critical for rejection. Lymphomas arising in IFN-γ- and IFN-γ-receptor-deficient mice had invariably lost antigen expression, suggesting that poor overall survival of these recipients was due to inefficient elimination of antigen-negative lymphoma variants. Antigen-dependent eradication of lymphoma cells in wild-type animals was dependent on cross-presentation of antigen by cells of the tumor stroma. These findings provide first evidence for an important role of the tumor stroma in T cell-mediated control of hematologic neoplasias and highlight the importance of incorporating stroma-targeting strategies into future immunotherapeutic approaches. 相似文献
202.
A Jain PS Baviskar S Kandasamy R Kumar R Singh S Kumar SK Agarwal P Joshi A Mitra 《Animal reproduction science》2012,132(3-4):159-168
A sequential medium was evaluated on the survival, activation and growth rates of caprine preantral follicles submitted to a long-term culture period, aiming to establish an ideal in vitro culture system. Ovarian fragments were cultured for 16 days in α-MEM(+) alone or supplemented with hormones (GH and/or FSH) added sequentially on different days of culture. Ovarian fragments were cultured in the first (days 0-8) and second (days 8-16) halves of the culture period, generating 10 treatments: α-MEM(+)/α-MEM(+), FSH/FSH, FSH/GH, FSH/FSH+GH, GH/GH, GH/FSH, GH/FSH+GH, FSH+GH/FSH+GH, FSH+GH/FSH and FSH+GH/GH. Follicle morphology, viability and ultrastructure were analyzed. After day 1 of culture, FSH treatments maintained the percentage of normal follicles similar to the fresh control. At day 16 of culture, the treatment FSH/GH showed the highest (P<0.05) percentage of normal follicles. The ultrastructure of follicles was preserved in the fresh control and FSH/GH treatment. Follicles cultured with FSH/GH had a higher (P<0.05) viability than α-MEM(+); however the viability was lower (P<0.05) when compared to the fresh control. The FSH/GH treatment showed the highest (P<0.05) percentage of follicular activation and secondary follicle formation and produced the largest (P<0.05) mean follicular diameter after 16 days of culture. In conclusion, a sequential medium supplemented with FSH followed by GH during a long-term culture maintains the survival, viability and ultrastructure of goat preantral follicles, and promotes activation and secondary follicles. 相似文献
203.
Padmanaban Sriram S.A. Syamkumar J. Sam Deva Kumar Sukumar Prabakar Rajasekaran Dhanabalan Nagarajan Vivekanandan 《Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)》2012,28(4):327-332
PurposeTo assess the potential of cone beam CT (CBCT) derived adaptive RapidArc treatment for esophageal cancers in reducing the dose to organs at risk (OAR).Methods and materialsTen patients with esophageal cancer were CT scanned in free breathing pattern. The PTV is generated by adding a 3D margin of 1 cm to the CTV as per ICRU 62 recommendations. The double arc RapidArc plan (Clin_RA) was generated for the PTV. Patients were setup using kV orthogonal images and kV-CBCT scan was acquired daily during first week of therapy, then weekly. These images were exported to the Eclipse TPS. The adaptive CTV which includes tumor and involved nodes was delineated in each CBCT image set for the length of the PTV. The composite CTV from first week CBCT was generated using Boolean union operator and 5 mm margin was added circumferentially to generate adaptive PTV (PTV1). Adaptive RapidArc plan (Adap_RA) was generated. NTCP and DVH of the OARs of the two plans were compared. Similarly, PTV2 was generated from weekly CBCT. PTV2 was evaluated for the coverage of 95% isodose of Adap_RA plan.ResultsThe PTV1 and PTV2 volumes covered by 95% isodose in adaptive plans were 93.51 ± 1.17% and 94.59 ± 1.43% respectively. The lung V10Gy, V20Gy and mean dose in Adap_RA plan was reduced by 17.43% (p = 0.0012), 34.64% (p = 0.0019) and 16.50% (p = 0.0002) respectively compared to Clin_RA. The Adap_RA plan reduces the heart D35% and mean dose by 17.35% (p = 0.0011) and 17.16% (p = 0.0012). No significant reduction in spinal cord and liver doses were observed. NTCP for the lung (0.42% vs. 0.08%) and heart (1.39% vs. 0.090%) was reduced significantly in adaptive plans.ConclusionThe adaptive re-planning strategy based on the first week CBCT dataset significantly reduces the doses and NTCP to OARs. 相似文献
204.
205.
Geetha Ramaswami Monica Kaushik Soumya Prasad Raman Sukumar David Westcott 《Biotropica》2016,48(5):638-644
In the past century, our understanding of the processes driving plant invasion and its consequences for natural and anthropogenic systems has increased considerably. However, the management of invasive plants remains a challenge despite ever more resources being allocated to their removal. Often invasive plants targeted for ‘eradication’ are well‐established, have multiple modes of reproduction, long‐term seed banks, and strong associations with native and non‐native mutualists that ensure dispersal and facilitate spread. The pantropical weed, Lantana camara (Lantana), is one of the most invasive woody plants globally. We illustrate that, for Lantana, eradication is an unrealistic management goal given the short‐term removal approaches, irrespective of the effectiveness of removal methods. We assessed the role of dispersal by avian frugivores in the recolonization of managed areas by Lantana in the seasonally dry, tropical forests of northern and southern India. We estimated the distribution of Lantana, its dispersal potential and the proximity between managed areas and source populations. We found that Lantana was dispersed by many generalist frugivorous birds and that most managed areas were well within the median dispersal distance from source plants facilitating rapid recolonization of managed areas. We conclude that given the difficulty of eradicating long‐established invasive plants, management practices should entail long‐term monitoring and control in priority areas for as long as Lantana occurs in the landscape. 相似文献
206.
Yuhuan Wang Anastasia Vlasova Daniel E. Velasquez Linda J. Saif Sukumar Kandasamy Efrat Kochba Yotam Levin Baoming Jiang 《PloS one》2016,11(11)
Live-attenuated oral rotavirus (RV) vaccines have lower efficacy in low income countries, and additionally are associated with a rare but severe adverse event, intussusception. We have been pursuing the development of an inactivated rotavirus vaccine (IRV) using the human rotavirus strain CDC-9 (G1P[8]) through parenteral immunization and previously demonstrated dose sparing and enhanced immunogenicity of intradermal (ID) unadjuvanted IRV using a coated microneedle patch in comparison with intramuscular (IM) administration in mice. The aim of this study was to evaluate the immune response and protection against RV infection and diarrhea conferred by the administration of the ID unadjuvanted IRV using the microneedle device MicronJet600® in neonatal gnotobiotic (Gn) piglets challenged with virulent Wa G1P[8] human RV. Three doses of 5 μg IRV when administered intradermally and 5 μg IRV formulated with aluminum hydroxide [Al(OH)3] when administered intramuscularly induced comparable rotavirus-specific antibody titers of IgA, IgG, IgG avidity index and neutralizing activity in sera of neonatal piglets. Both IRV vaccination regimens protected against RV antigen shedding in stools, and reduced the cumulative diarrhea scores in the piglets. This study demonstrated that the ID and IM administrations of IRV are immunogenic and protective against RV-induced diarrhea in neonatal piglets. Our findings highlight the potential value of an adjuvant sparing effect of the IRV ID delivery route. 相似文献
207.
Differential Bvg phase-dependent regulation and combinatorial role in pathogenesis of two Bordetella paralogs, BipA and BcfA 下载免费PDF全文
To successfully colonize their mammalian hosts, many bacteria produce multiple virulence factors that play essential roles in disease processes and pathogenesis. Some of these molecules are adhesins that allow efficient attachment to host cells, a prerequisite for successful host colonization. Bordetella spp. express a number of proteins which either play a direct role in attachment to the respiratory epithelia or exhibit similarity to known bacterial adhesins. One such recently identified protein is BipA. Despite the similarity of BipA to intimins and invasins, deletion of this protein from B. bronchiseptica did not result in any significant defect in respiratory tract colonization. In this study, we identified an open reading frame in B. bronchiseptica, designated bcfA (encoding BcfA [bordetella colonization factor A]), that is similar to bipA. In contrast to the maximal expression of bipA in the Bvg intermediate (Bvg(i)) phase, bcfA is expressed at high levels in both the Bvg(+) and Bvg(i) phases. We show here that BvgA and phosphorylated BvgA bind differentially to the bcfA promoter region. Utilizing immunoblot assays, we found that BcfA is localized to the outer membrane and that it is expressed during animal infection. While deletion of either bipA or bcfA did not significantly affect respiratory tract colonization, concomitant deletion of both genes resulted in a defect in colonization of the rat trachea. Our results indicate that the two paralogous proteins have a combinatorial role in mediating efficient respiratory tract colonization. 相似文献
208.
Osman A. Gutiérrez David M. Stelly Sukumar Saha Johnie N. Jenkins Jack C. McCarty Jr Dwaine A. Raska Brian E. Scheffler 《Molecular breeding : new strategies in plant improvement》2009,23(4):693-707
A combination of previously mapped and unmapped non-redundant SSR loci, using 381 primer pairs were chromosomally and sub-chromosomally
localized by deficiency analysis of two sets of quasi-isogenic interspecific Gossypium hirsutum L. hypoaneuploid F1 hybrids involving Gossypium barbadense L. and Gossypium tomentosum (Nuttall ex Seemann). Polymorphisms were detected for 369 SSR primer pairs. A total of 318 SSR loci were rendered deficient
by the available hypoaneuploid stocks, which included primary monosomics (2n = 51), monotelodisomics and duplication-deficient (segmental trisomic–monosomic) (2n = 52) types. Chromosomal associations were newly determined for 123 SSR loci, of which 90, 106 and 73 were polymorphic in
G. tomentosum, G. barbadense, and both sets, respectively. The deficiency tests independently confirmed the recent identifications of linkage groups (LG)
A01, A02, A03 and D08 to be chromosome (Chr)-13, Chr-8, Chr-11 and Chr-19, respectively, and collectively delimited LG D02
and D03 to Chr-21 and 24, and their homeologs to Chr-8 and 11. Segmental homeology was detected between Chr-2 and Chr-17 loci,
adding to evidence of segmental homeology between Chr-2 and 3 versus Chr-14 and 17. The 318 non-redundant SSR loci localized
in this study will enhance the construction of linkage maps and QTL identification in molecular marker assisted selection
since the confirmed and newly discovered SSR loci can serve as anchor loci for their respective chromosomes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
209.
Ibrokhim Y. Abdurakhmonov Sukumar Saha Jonnie N. Jenkins Zabardast T. Buriev Shukhrat E. Shermatov Brain E. Scheffler Alan E. Pepper John Z. Yu Russell J. Kohel Abdusattor Abdukarimov 《Genetica》2009,136(3):401-417
Cotton is the world’s leading cash crop, but it lags behind other major crops for marker-assisted breeding due to limited
polymorphisms and a genetic bottleneck through historic domestication. This underlies a need for characterization, tagging,
and utilization of existing natural polymorphisms in cotton germplasm collections. Here we report genetic diversity, population
characteristics, the extent of linkage disequilibrium (LD), and association mapping of fiber quality traits using 202 microsatellite
marker primer pairs in 335 G. hirsutum germplasm grown in two diverse environments, Uzbekistan and Mexico. At the significance threshold (r
2 ≥ 0.1), a genome-wide average of LD extended up to genetic distance of 25 cM in assayed cotton variety accessions. Genome
wide LD at r
2 ≥ 0.2 was reduced to ~5–6 cM, providing evidence of the potential for association mapping of agronomically important traits
in cotton. Results suggest linkage, selection, inbreeding, population stratification, and genetic drift as the potential LD-generating
factors in cotton. In two environments, an average of ~20 SSR markers was associated with each main fiber quality traits using
a unified mixed liner model (MLM) incorporating population structure and kinship. These MLM-derived significant associations
were confirmed in general linear model and structured association test, accounting for population structure and permutation-based
multiple testing. Several common markers, showing the significant associations in both Uzbekistan and Mexican environments,
were determined. Between 7 and 43% of the MLM-derived significant associations were supported by a minimum Bayes factor at
‘moderate to strong’ and ‘strong to very strong’ evidence levels, suggesting their usefulness for marker-assisted breeding
programs and overall effectiveness of association mapping using cotton germplasm resources.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
210.
Determination of chromosomes or chromosome arms with desirable genes in different inbred lines and/or crosses should provide useful genetic information for crop improvement. In this study, we applied a modified additive-dominance model to analyze a data set of 13 cotton chromosome substitution lines and their recurrent parent TM-1, five commercial cultivars, and their 70 F(2) hybrids. The chromosome additive and dominance variance components for eight agronomic and fiber traits were determined. On average, each chromosome or chromosome arm was associated with 6.5 traits in terms of additive and/or dominance effects. The chromosomes or chromosome arms, which contributed significant additive variances for the traits investigated, included 2, 16, 18, 25, 5sh (short arm), 14sh, 15sh, 22sh, and 22Lo (long arm). Chromosome additive effects were also predicted in this study. The results showed that CS-B 25 was favorably associated with several fiber traits, while FM966 was favorably associated with both yield and fiber traits with alleles on multiple chromosomes or chromosome arms. Thus, this study should provide valuable genetic information on pure line development for several improved traits such as yield and fiber quality. 相似文献