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991.
Radioligand therapies have opened new treatment avenues for cancer patients. They offer precise tumor targeting with a favorable efficacy-to-toxicity profile. Specifically, the kidneys, once regarded as the critical organ for radiation toxicity, also show excellent tolerance to radiation doses as high as 50–60 Gy in selected cases. However, the number of nephrons that form the structural and functional units of the kidney is determined before birth and is fixed. Thus, loss of nephrons secondary to any injury may lead to an irreversible decline in renal function over time. Our primary understanding of radiation-induced nephropathy is derived from the effects of external beam radiation on the renal tissue. With the growing adoption of radionuclide therapies, considerable evidence has been gained with regard to the occurrence of renal toxicity and its associated risk factors. In this review, we discuss the radionuclide therapies associated with the risk of nephrotoxicity, the present understanding of the factors and mechanisms that contribute to renal injury, and the current and potential methods for preventing, identifying, and managing nephrotoxicity, specifically acute onset nephropathies. 相似文献
992.
Parthasarathy Manikandan Sankaran Sandhya Kavyashree Nadig Souradip Paul Narayanaswamy Srinivasan Ulli Rothweiler Mahavir Singh 《Nucleic acids research》2022,50(3):1687
Toxin–antitoxin (TA) systems are proposed to play crucial roles in bacterial growth under stress conditions such as phage infection. The type III TA systems consist of a protein toxin whose activity is inhibited by a noncoding RNA antitoxin. The toxin is an endoribonuclease, while the antitoxin consists of multiple repeats of RNA. The toxin assembles with the individual antitoxin repeats into a cyclic complex in which the antitoxin forms a pseudoknot structure. While structure and functions of some type III TA systems are characterized, the complex assembly process is not well understood. Using bioinformatics analysis, we have identified type III TA systems belonging to the ToxIN family across different Escherichia coli strains and found them to be clustered into at least five distinct clusters. Furthermore, we report a 2.097 Å resolution crystal structure of the first E. coli ToxIN complex that revealed the overall assembly of the protein-RNA complex. Isothermal titration calorimetry experiments showed that toxin forms a high-affinity complex with antitoxin RNA resulting from two independent (5′ and 3′ sides of RNA) RNA binding sites on the protein. These results further our understanding of the assembly of type III TA complexes in bacteria. 相似文献
993.
994.
995.
The cells of the ovarian transmitting tissue of Lilium regaleare papilla shaped and form and epithelium on the placenta.Their ultrastructural organization and differentiation from1 d before to 7 d after anthesis is presented. These placentacells are typical transfer cells with a prominent secretionzone similar to that known from stylar canal cells. After anthesisthe secretion zone continues to grow by addition of vesiclefrom the numerous dictyosomes. Maximum depth of this zone isreached by day 4 after anthesis. The outer surface of the cellwall is distinctly rugged on cell maturation and the outermostlayer is corroded. The ER system undergoes transition from asmooth to a granular condition. Before anthesis there is a centralvacuole which at anthesis is reduced to a system of small vauoles.These are supplemented by autophagic vacuoles formed from theER. Such vacuoles are found near the secretion zone and mayalso fuse with the plasmalemma. The cuticle is sloughed andsecretion commences before anthesis. Accumulations of vesiclesfound in the nucleus and occasional connections between suchvesicles and the inner membrane of the nuclear envelope indicatethe presence of a nuclear network. Protein crystals are presentin the cytoplasm and the nucleus. The starch grains in the plastidsare digested after anthesis, but new ones are formed by days6 and 7.Copyright 1995, 1999 Academic Press Lilium regale, transmitting tissue, placenta, secretion, nuclear reticulum, transfer cells 相似文献
996.
Surendra Singh 《FEMS microbiology letters》1988,56(3):281-283
Abstract The utilization of urea was studied in the cyanobacterium Anabaena doliolum . The uptake of urea was unaltered in the presence of ammonium. The cells receiving ATP exogenously showed an induced level of urea-uptake as compared with the control cells. Urease inhibitor acetohydroxamic acid and hydroxyurea as well as glutamate analogue, MSO, did not affect the uptake of urea. These results suggest: (1) urea and ammonia have different uptake sites, (2) urea-uptake is an energy dependent process, and (3) during short-term experiments, urea uptake is not linked with the enzyme urease or the ammonium assimilating enzyme glutamine synthetase. 相似文献
997.
Abstract Genome analysis of Pseudomonas aeruginosa was performed by digestion with rare-cutting restriction endonucleases and subsequent one- and two-dimensional field inversion gel electrophoresis (FIGE). The frequency of chromosomal recognition sites increased in the order Spe I, Dra I, Xba I, Ssp I, Nhe I. The genome size of strain PAO and the 17 IATS strains varied from 4.4 × 106 to 5.4 × 106 base pairs. Double restriction digests and two-dimensional FIGE provide a genome fingerprint which is useful for the identification and typing of the respective strains. 相似文献
998.
999.
Nima Khalilisamani Peter Campbell Thomson Herman Willem Raadsma Mehar Singh Khatkar 《Heredity》2022,128(3):178
Estimating heritability based on individual phenotypic and genotypic measurements can be expensive and labour-intensive in commercial aquaculture breeding. Here, the feasibility of estimating heritability using within-family means of phenotypes and allelic frequencies was investigated. Different numbers of full-sib families and family sizes across ten generations with phenotypic and genotypic information on 10 K SNPs were analysed in ten replicates. Three scenarios, representing differing numbers of pools per family (one, two and five) were considered. The results showed that using one pool per family did not reliably estimate the heritability of family means. Using simulation parameters appropriate for aquaculture, at least 200 families of 60 progeny per family divided equally in two pools per family was required to estimate the heritability of family means effectively. Although application of five pools generated more within- and between- family relationships, it reduced the number of individuals per pool and increased within-family residual variation, hence, decreased the heritability of family means. Moreover, increasing the size of pools resulted in increasing the heritability of family means towards one. In addition, heritability of family mean estimates were higher than family heritabilities obtained from Falconer’s formula due to lower intraclass correlation estimate compared to the coefficient of relationship.Subject terms: Genome evolution 相似文献
1000.
Evidence for photosynthetic independence of viral multiplication in cyanophage LPP-1 infected cyanobacterium Phormidium uncinatum 总被引:1,自引:0,他引:1
P.S. Bisen Surabhi Audholia H.D. Shukla Amit Gupta D.P. Singh 《FEMS microbiology letters》1988,52(3):225-228
Abstract Pigment decomposition, oxygen evolution and CO2 fixation were measured in the cyanobacterium Phormidium uncinatum after infection with cyanophage LPP-1, under light and dark conditions. A gradual decrease in para benzoquinone supported O2 evolution, chlorophyll a and phycocyanin level were noticed after 6 h of infection. These results demonstrated decreased photosynthetic activity of the host P. uncinatum prior to the start of LPP-1 multiplication. Metabolic inhibitor investigations confirmed that the cyanophage LPP-1 multiplication was independent of host photosynthesis. 相似文献