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61.
A series of benzothiazole and benzoxazole linked pyrrolobenzodiazepine conjugates attached through different alkane or alkylamide spacers was prepared. Their anticancer activity, DNA thermal denaturation studies, restriction endonuclease digestion assay and flow cytometric analysis in human melanoma cell line (A375) were investigated. One of the compounds of the series 17d showed significant anticancer activity with promising DNA-binding ability and apoptosis caused G0/G1 phase arrest at sub-micromolar concentrations. To ascertain the binding mode and understand the structural requirement of DNA binding interaction, molecular docking studies using gold program and more rigorous 2 ns molecular dynamic simulations using Molecular Mechanics-Poisson–Boltzman Surface Area (MM-PBSA) approach including the explicit solvent were carried out. Further, the compound 17d was evaluated for in vivo efficacy studies in human colon cancer HT29 xenograft mice.  相似文献   
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Benzothiadiazine-pyrrolobenzodiazepine conjugates linked through different alkane spacers have been prepared. These new classes of hybrid molecules exhibit cytotoxicity against many cancer cell lines. Their DNA thermal denaturation studies have been carried out and one of the compounds (4b) elevates the DNA helix melting temperature of the CT-DNA by 6.7 degrees C after incubation for 36 h.  相似文献   
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Background

Leprosy is the most common treatable peripheral nerve disorder worldwide with periods of acute neuritis leading to functional impairment of limbs, ulcer formation and stigmatizing deformities. Since the hallmarks of leprosy are nerve enlargement and inflammation, we used high-resolution sonography (US) and color Doppler (CD) imaging to demonstrate nerve enlargement and inflammation.

Methology/Principal Findings

We performed bilateral US of the ulnar (UN), median (MN), lateral popliteal (LP) and posterior tibial (PT) nerves in 20 leprosy patients and compared this with the clinical findings in these patients and with the sonographic findings in 30 healthy Indian controls.The nerves were significantly thicker in the leprosy patients as compared to healthy controls (p<0.0001 for each nerve). The two patients without nerve enlargements did not have a type 1 or type 2 reaction or signs of neuritis. The kappa for clinical palpation and nerve enlargement by sonography was 0.30 for all examined nerves (0.32 for UN, 0.41 for PN and 0.13 for LP). Increased neural vascularity by CD imaging was present in 39 of 152 examined nerves (26%). Increased vascularity was observed in multiple nerves in 6 of 12 patients with type 1 reaction and in 3 of 4 patients with type 2 reaction. Significant correlation was observed between clinical parameters of grade of thickening, sensory loss and muscle weakness and US abnormalities of nerve echotexture, endoneural flow and cross-sectional area (p<0.001).

Conclusions/Significance

We conclude that clinical examination of enlarged nerves in leprosy patients is subjective and inaccurate, whereas sonography provides an objective measure of nerve damage by showing increased vascularity, distorted echotexture and enlargement. This damage is sonographically more extensive and includes more nerves than clinically expected.  相似文献   
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BackgroundThe purpose of this study was to compare four 3D conformal radiation techniques in treatment of left breast cancer patients.Materials and methodsRadiation was planned for 20 patients to the left breast and regional lymph nodes using four techniques: partially wide tangents, photon-photon mix, photon-electron mix and 30/70 photon-electron mix. All plans were evaluated for internal mammary nodes (IMN) coverage, hotspot and normal tissue constraints.ResultThe 85% of planning target volume (PTV) coverage was lesser for upper IMN than the lower IMN (below the lower border of the clavicular head) for all four techniques. The lower IMN coverage was better for partially wide tangent (80.46%) and photon-photon mix (88.88%). The lowest value of hotspot was seen in the partially wide tangent technique (112.69% ± 1.92). Hotspot is unacceptably high in both photon-electron mix and 30/70 photon-electron mix (> 120%). Left lung mean dose for all techniques on a pair-wise comparison showed no statistical difference. Left lung V20 values for partially wide tangent was 37.56% ± 8.17 and for photon-photon mix it was 40.49% ± 3.36. The mean heart dose with partially wide tangent was 9.43 ± 3.15 Gy and with photon-photon mix it was 10.10 ± 2.70 Gy. The mean heart dose for photon-electron mix was 7.56 ± 1.95 Gy and for 30/70 photon-electron mix it was 7.98 ± 2.16 Gy.ConclusionNo single technique satisfies all the criteria. The decision should be made on a case-by-case basis, considering the anatomy of the patient, availability of electron facilities and setup accuracy and reproducibility.  相似文献   
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Background

Identifying QTLs/genes for iron and zinc in rice grains can help in biofortification programs. Genome wide mapping showed 14 QTLs for iron and zinc concentration in unpolished rice grains of F7 RILs derived from Madhukar × Swarna. One line (HL) with high Fe and Zn and one line (LL) with low Fe and Zn in unpolished rice were compared with each other for gene expression using qPCR. 7 day old seedlings were grown in Fe + and Fe − medium for 10 days and RNA extracted from roots and shoots to determine the response of 15 genes in Fe − conditions.

Results

HL showed higher upregulation than LL in shoots but LL showed higher upregulation than HL in roots. YSL2 was upregulated only in HL roots and YSL15 only in HL shoots and both up to 60 fold under Fe − condition. IRT2 and DMAS1 were upregulated 100 fold and NAS2 1000 fold in HL shoot. NAS2, IRT1, IRT2 and DMAS1 were upregulated 40 to 100 fold in LL roots. OsZIP8, OsNAS3, OsYSL1 and OsNRAMP1 which underlie major Fe QTL showed clear allelic differences between HL and LL for markers flanking QTL. The presence of iron increasing QTL allele in HL was clearly correlated with high expression of the underlying gene. OsZIP8 and OsNAS3 which were within major QTL with increasing effect from Madhukar were 8 fold and 4 fold more expressed in HL shoot than in LL shoot. OsNAS1, OsNAS2, OsNAS3, OsYSL2 and OsYSL15 showed 1.5 to 2.5 fold upregulation in flag leaf of HL when compared with flag leaf of Swarna.

Conclusion

HL and LL differed in root length, Fe concentration and expression of several genes under Fe deficiency. The major distinguishing genes were NAS2, IRT2, DMAS1, and YSL15 in shoot and NAS2, IRT1, IRT2, YSL2, and ZIP8 in roots. The presence of iron increasing QTL allele in HL at marker locus close to genes also increased upregulation in HL.  相似文献   
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For non-model organisms that do not have sequence information readily available, amplified fragment length polymorphism (AFLP) is a well-established technique that can be used for genomic mapping applications such as genetic diversity studies or phylogenetic studies. While AFLP can be performed on a variety of systems, including gel-based systems that require multiple labor-intensive steps, the availability of a more automated system that integrates the assay, electrophoresis platform, and analysis software could enable researchers to greatly increase their throughput and facilitate routine AFLP analysis. We demonstrate the use of such a system for AFLP analysis on Hedysarum species. AFLP assays performed on samples belonging to two different species isolated from Utah identified different varieties that clustered as expected from their actual locations.  相似文献   
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