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1.
Modification of 5'-32P-labelled octadecadeoxyribonucleotide d(pC5A8C5) (III) with octathymidylate methylphosphonate derivatives bearing both 3'- and 5'-terminal alkylating 4-(N-2-chloroethyl-N-methylamino)benzylphosphoamide residue has been investigated. Yield in the modification depends on configuration of methylphosphonate fragment, in case of Rp-isomer it may amount to 90%. Specificity of alkylation of nucleic acide target (III) by reagents based on the oligonucleotide methylphosphonates is almost the same as by reagents based on the oligonucleotides having phosphodiester internucleotide bonds. 相似文献
2.
Efficiency of the intracomplex alkylation of octadecadeoxyribonucleotide d(pC5A8C5) (target) by Rp- and Sp-individual diastereomers of the methylphosphonate octathymidylate 4-(N-methyl-N-2-chloroethylamino)benzyl phosphoramide (-pNHCH2RCl) derivatives bearing an additional N-(2-hydroxyethyl)phenazinium residue (phn), viz. ClRCH2NHpTp.(TpTp)3TpNH(CH2)2NHPhn (I) and PhnNH(CH2)2NHpTp(TpTp)3TpNHCH2RCl (II) (p = -OP(O) (CH3)O-), has been investigated. Stabilisation of the complementary complex formed by the target oligonucleotide and methylphosphonate oligonucleotide derivatives by the Phn group considerably rose the efficiency of the intracomplex alkylation of the target as compared with alkylation by reagents without Phn. RP-isomeric derivatives of (I) and (II) proved to be the most effective alkylating reagents. Specificity of alkylation of nucleic acid target by reagents (I) and (II) is studied. 相似文献
3.
Amirkhanov N. V. Bardasheva A. V. Tikunova N. V. Pyshnyi D. V. 《Russian Journal of Bioorganic Chemistry》2021,47(3):681-690
Russian Journal of Bioorganic Chemistry - We have studied the antimicrobial and hemolytic activity of synthetic antimicrobial peptides (SAMPs), i.e., Arg9Phe2 (P1-Arg), Lys9Phe2 (P2-Lys), and... 相似文献
4.
R. N. Amirkhanov V. F. Zarytova N. V. Amirkhanov 《Russian Journal of Bioorganic Chemistry》2013,39(6):629-638
When creating effective drugs, it is important not only to transport them into cells, but also allow them to be released from the “transporter” after the delivery. It was shown that the dissociation of peptide nucleic acids (PNA) from TiO2 · PL · DNA/PNA nanocomposites occurred according to a typical thermal denaturation, and polylysine (PL) in the nanocomposite has almost no effect on the dissociation. These data suggest that the immobilization of PNA in the TiO2 · PL · DNA/PNA nanocomposite is reversible and PNA can be easily released from TiO2 carrier into solution. In contrast to that, the dissociation of DNA/DNA and DNA/PNA duplexes in physiological solution in the presence of PL was not observed. PL in solution dramatically influences the dependence of the optical density on temperature and time for DNA/DNA duplexes and to a lesser degree for DNA/PNA duplexes. It has been assumed that PL and DNA/DNA duplexes in physiological solutions form triple polycomplexes (DNA/DNA · PL) m , which can aggregate and precipitate. PL in solution can also interact with DNA/PNA duplexes to form monocomplexes PL · (DNA/PNA) n consisting of one PL chain and one or more (n) DNA/PNA duplexes. Although these monocomplexes do not precipitate, the dissociation of DNA/PNA duplexes from them is complicated. 相似文献
5.
Yulia Kundel Nicola J. Nasser Ofer Purim Rinat Yerushalmi Eyal Fenig Raphael M. Pfeffer Salomon M. Stemmer Shulamith Rizel Zvi Symon Bella Kaufman Aaron Sulkes Baruch Brenner 《PloS one》2013,8(7)
Background
Pain from bone metastases of breast cancer origin is treated with localized radiation. Modulating doses and schedules has shown little efficacy in improving results. Given the synergistic therapeutic effect reported for combined systemic chemotherapy with local radiation in anal, rectal, and head and neck malignancies, we sought to evaluate the tolerability and efficacy of combined capecitabine and radiation for palliation of pain due to bone metastases from breast cancer.Methodology/Principal Findings
Twenty-nine women with painful bone metastases from breast cancer were treated with external beam radiation in 10 fractions of 3 Gy, 5 fractions a week for 2 consecutive weeks. Oral capecitabine 700 mg/m2 twice daily was administered throughout radiation therapy. Rates of complete response, defined as a score of 0 on a 10-point pain scale and no increase in analgesic consumption, were 14% at 1 week, 38% at 2 weeks, 52% at 4 weeks, 52% at 8 weeks, and 48% at 12 weeks. Corresponding rates of partial response, defined as a reduction of at least 2 points in pain score without an increase in analgesics consumption, were 31%, 38%, 28%, 34% and 38%. The overall response rate (complete and partial) at 12 weeks was 86%. Side effects were of mild intensity (grade I or II) and included nausea (38% of patients), weakness (24%), diarrhea (24%), mucositis (10%), and hand and foot syndrome (7%).Conclusions/Significance
External beam radiation with concurrent capecitabine is safe and tolerable for the treatment of pain from bone metastases of breast cancer origin. The overall and complete response rates in our study are unusually high compared to those reported for radiation alone. Further evaluation of this approach, in a randomized study, is warranted.Trial Registration
ClinicalTrials.gov NCT01784393 NCT01784393相似文献6.
Rinat Friedman Ayelet Haimy Yoram Epstein 《Computer methods in biomechanics and biomedical engineering》2019,22(3):229-242
Despite the progress in developing personal combat-protective gear, eye and brain injuries are still widely common and carry fatal or long-term repercussions. The complex nature of the cranial tissues suggests that simple methods (e.g. crash-dummies) for testing the effectiveness of personal protective gear against non-penetrating impacts are both expensive and ineffective, and there are ethical issues in using animal or cadavers. The present work presents a versatile testing framework for quantitatively evaluating protective performances of head and eye combat-protective gear, against non-penetrating impacts. The biomimetic finite element (FE) head model that was developed provides realistic representation of cranial structure and tissue properties. Simulated crash impact results were validated against a former cadaveric study and by using a crash-phantom developed in our lab. The model was then fitted with various helmet and goggle designs onto which a non-penetrating ballistic impact was applied. Example data show that reduction of the elastic and shear moduli by 30% and 80% respectively of the helmet outer Kevlar-29 layer, lowered intracranial pressures by 20%. Our modeling suggests that the level of stresses that develop in brain tissues, which ultimately cause the brain damage, cannot be predicted solely by the properties of the helmet/goggle materials. We further found that a reduced contact area between goggles and face is a key factor in reducing the mechanical loads transmitted to the optic nerve and eye balls following an impact. Overall, this work demonstrates the simplicity, flexibility and usefulness for development, evaluation, and testing of combat-protective equipment using computational modeling.
- Highlights
A finite element head model was developed for testing head gear.
Reduced helmet’s outer layer elastic and shear moduli lowered intracranial stresses.
Gear material properties could not fully predict impact-related stress in the brain.
Reduced goggles-face contact lowered transmitted loads to the optic nerve and eyes.
7.
Augusto Varese Joy Nakawesi Ana Farias Freja C. M. Kirsebom Michelle Paulsen Rinat Nuriev Cecilia Johansson 《PLoS pathogens》2022,18(2)
Respiratory syncytial virus (RSV) can cause bronchiolitis and viral pneumonia in young children and the elderly. Lack of vaccines and recurrence of RSV infection indicate the difficulty in eliciting protective memory immune responses. Tissue resident memory T cells (TRM) can confer protection from pathogen re-infection and, in human experimental RSV infection, the presence of lung CD8+ TRM cells correlates with a better outcome. However, the requirements for generating and maintaining lung TRM cells during RSV infection are not fully understood. Here, we use mouse models to assess the impact of innate immune response determinants in the generation and subsequent expansion of the TRM cell pool during RSV infection. We show that CD8+ TRM cells expand independently from systemic CD8+ T cells after RSV re-infection. Re-infected MAVS and MyD88/TRIF deficient mice, lacking key components involved in innate immune recognition of RSV and induction of type I interferons (IFN-α/β), display impaired expansion of CD8+ TRM cells and reduction in antigen specific production of granzyme B and IFN-γ. IFN-α treatment of MAVS deficient mice during primary RSV infection restored TRM cell expansion upon re-challenge but failed to recover TRM cell functionality. Our data reveal how innate immunity, including the axis controlling type I IFN induction, instructs and regulates CD8+ TRM cell responses to RSV infection, suggesting possible mechanisms for therapeutic intervention. 相似文献
8.
The A locus that controls anthocyanin accumulation in pepper encodes a MYB transcription factor homologous to Anthocyanin2 of Petunia 总被引:1,自引:0,他引:1
Borovsky Y Oren-Shamir M Ovadia R De Jong W Paran I 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,109(1):23-29
Pepper plants containing the dominant A gene accumulate anthocyanin pigments in the foliage, flower and immature fruit. We previously mapped A to pepper chromosome 10 in the F2 progeny of a cross between 5226 (purple-fruited) and PI 159234 (green-fruited) to a region that corresponds, in tomato, to the location of Petunia anthocyanin 2 (An2), a regulator of anthocyanin biosynthesis. This suggested that A encodes a homologue of Petunia An2. Using the sequences of An2 and a corresponding tomato expressed sequence tag, we isolated a pepper cDNA orthologous to An2 that cosegregated with A. We subsequently determined the expression of A by Northern analysis, using RNA extracted from fruits, flowers and leaves of 5226 and PI 159234. In 5226, expression was detected in all stages of fruit development and in both flower and leaf. In contrast, A was not expressed in the sampled tissues in PI 159234. Genomic sequence comparison of A between green- and purple-fruited genotypes revealed no differences in the coding region, indicating that the lack of expression of A in the green genotypes can be attributed to variation in the promoter region. By analyzing the expression of the structural genes in the anthocyanin biosynthetic pathway in 5226 and PI 159234, it was determined that, similar to Petunia, the early genes in the pathway are regulated independently of A, while expression of the late genes is A-dependent.Communicated by R. Hagemann 相似文献
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10.
Marek's disease virus (MDV) productive replication occurs in the feather follicle epithelium and the feather tips are valuable both for research and disease diagnosis. Three novel applications of feather tip extracts are described now: (A). As a source of DNA for amplifying either MDV and/or ALV-J. In two clinical situations a marked advantage was obtained compared to blood and organs; in broiler breeder flocks with a mixed MDV and ALV-J infection, and in young broilers with neurological Marek's disease (MD). (B). Separation of the large ( approximately 200 kbp) MDV genome directly from the infected chickens. Using pulsed field gel electrophoresis, the DNA extracted from tumors or feather tips was separated and hybridized to a 132 bp tandem repeat MDV probe. Compared to 2/55 polymerase chain reaction (PCR) positive tumor samples, 15/61 feather tip extracts contained whole MDV genomes. (C). Experimental MDV infection was induced by the mucosal route by dripping feather tip extract to the eye and mouth of the bird. That attempted to reproduce the native infection process, however the use of extracts, instead of dry feather dust was a compromise, aimed to synchronize the infection. In one trial, tumors were induced 6 weeks after dripping day-old broilers, while in another, feather tips were PCR positive 16 days after dripping of 2-month-old layers. 相似文献