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91.
Transgenic Robinia pseudoacacia plants were obtained by Agrobacterium tumefaciens mediated gene transfer. Agrobacterium strain LBA4404 harbouring a binary vector that contained the chimeric neomycin phosphotransferase II (NPTII) and beta-glucuronidase (GUS) genes was co-cultivated with hypocotyl segments of in vitro raised seedlings of Robinia. Parameters important for high efficiency regeneration and transformation rates included type of explant, pre-conditioning of explants and appropriate length of co-cultivation period with Agrobacterium. A transformation frequency 16.67% was obtained by 48 hr of pre-conditioning followed by 48 hr of co-cultivation. Transformed tissue was selected by the ability to grow on kanamycin containing medium. Successful regeneration was followed after histochemical GUS assay for the detection of transgenic tissue. This transformation procedure has the potential to expand the range of genetic variation in Robinia.  相似文献   
92.
The polymerization of FtsZ is a finely regulated process that plays an essential role in the bacterial cell division process. However, only a few modulators of FtsZ polymerization are known. We identified monosodium glutamate as a potent inducer of FtsZ polymerization. In the presence of GTP, glutamate enhanced the rate and extent of polymerization of FtsZ in a concentration-dependent manner; approximately 90% of the protein was sedimented as polymer in the presence of 1 m glutamate. Electron micrographs of glutamate-induced polymers showed large filamentous structures with extensive bundling. Furthermore, glutamate strongly stabilized the polymers against dilution-induced disassembly, and it decreased the GTPase activity of FtsZ. Calcium induced FtsZ polymerization and bundling of FtsZ polymers; interestingly, although 1 m glutamate produced a larger light-scattering signal than produced by 10 mm calcium, the amount of polymer sedimented in the presence of 1 m glutamate and 10 mm calcium was similar. Thus, the increased light scattering in the presence of glutamate must be due to its ability to induce more extensive bundling of FtsZ polymers than calcium. The data suggest that calcium and glutamate might induce FtsZ polymerization by different mechanisms.  相似文献   
93.
OBJECTIVE: To differentiate hyperplastic nodules (HPN), follicular adenoma (FA) and follicular carcinoma (FCA) of the thyroid by cytomorphologic features combined with argyrophilic nucleolar organizer regions (AgNORs) and Ki-67 proliferative markers on fine needle aspiration cytology. STUDY DESIGN: Cytomorphologic patterns, along with two proliferation markers, Ki-67 and AgNORs, in fine needle aspirates of 123 histologically confirmed cases of thyroid follicular lesions, including 39 hyperplastic nodules, 70 follicular adenomas and 14 cases of follicular carcinomas, were recorded. RESULTS: Mean AgNOR (mAgNOR) counts and Ki-67 labelling index (LI) were consistently higher in FCA in comparison to FA and HPN irrespective of the cytologic patterns in fine needle aspiration smears. Between benign and malignant lesions, an overlap of 1.83% at the cutoff point of 4.0 was observed in cases of mAgNORs, whereas it was 11.09% at a cutoff of 5.0 in cases of Ki-67 LI. CONCLUSION: mAgNOR counting in fine needle aspiration smears is more sensitive, simple and cost effective as compared to Ki-67 LI for differentiating between benign and malignant thyroid follicular neoplasms.  相似文献   
94.
Gupta  R. K.  Kour  Ramandeep  Gani  Mudasir  Guroo  M. A.  Bali  Kamlesh 《BioControl》2022,67(1):49-61
BioControl - The efficiency of four species of wax degrading bacteria, Serratia marcescens (Bizio) (Enterobacterales:Yersiniaceae), Pseudomonas putida (Trevisan) (Pseudomonadales:...  相似文献   
95.
With increasing structural information on proteins, the opportunity to understand physical forces governing protein folding is also expanding. One of the significant non‐covalent forces between the protein side chains is aromatic–aromatic interactions. Aromatic interactions have been widely exploited and thoroughly investigated in the context of folding, stability, molecular recognition, and self‐assembly processes. Through this review, we discuss the contribution of aromatic interactions to the activity and stability of thermophilic, mesophilic, and psychrophilic proteins. Being hydrophobic, aromatic amino acids tend to reside in the protein hydrophobic interior or transmembrane segments of proteins. In such positions, it can play a diverse role in soluble and membrane proteins, and in α‐helix and β‐sheet stabilization. We also highlight here some excellent investigations made using peptide models and several approaches involving aryl–aryl interactions, as an increasingly popular strategy in protein and peptide engineering. A recent survey described the existence of aromatic clusters (trimer, tetramer, pentamer, and higher order assemblies), revealing the self‐associating property of aryl groups, even in folded protein structures. The application of this self‐assembly of aromatics in the generation of modern bionanomaterials is also discussed.  相似文献   
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97.
BackgroundThe prevalence of chronic kidney disease (CKD) is high in general populations around the world. Targeted testing and screening for CKD are often conducted to help identify individuals that may benefit from treatment to ameliorate or prevent their disease progression.AimsThis systematic review examines the methods used in economic evaluations of testing and screening in CKD, with a particular focus on whether test accuracy has been considered, and how analysis has incorporated issues that may be important to the patient, such as the impact of testing on quality of life and the costs they incur.MethodsArticles that described model-based economic evaluations of patient testing interventions focused on CKD were identified through the searching of electronic databases and the hand searching of the bibliographies of the included studies.ResultsThe initial electronic searches identified 2,671 papers of which 21 were included in the final review. Eighteen studies focused on proteinuria, three evaluated glomerular filtration rate testing and one included both tests. The full impact of inaccurate test results was frequently not considered in economic evaluations in this setting as a societal perspective was rarely adopted. The impact of false positive tests on patients in terms of the costs incurred in re-attending for repeat testing, and the anxiety associated with a positive test was almost always overlooked. In one study where the impact of a false positive test on patient quality of life was examined in sensitivity analysis, it had a significant impact on the conclusions drawn from the model.ConclusionFuture economic evaluations of kidney function testing should examine testing and monitoring pathways from the perspective of patients, to ensure that issues that are important to patients, such as the possibility of inaccurate test results, are properly considered in the analysis.  相似文献   
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99.
The high-quality rice genome sequence is serving as a reference for comparative genome analysis in crop plants, especially cereals. However, early comparisons with bread wheat showed complex patterns of conserved synteny (gene content) and colinearity (gene order). Here, we show the presence of ancient duplicated segments in the progenitor of wheat, which were first identified in the rice genome. We also show that single-copy (SC) rice genes, those representing unique matches with wheat expressed sequence tag (EST) unigene contigs in the whole rice genome, show more than twice the proportion of genes mapping to syntenic wheat chromosome as compared to the multicopy (MC) or duplicated rice genes. While 58.7% of the 1,244 mapped SC rice genes were located in single syntenic wheat chromosome groups, the remaining 41.3% were distributed randomly to the other six non-syntenic wheat groups. This could only be explained by a background dispersal of genes in the genome through transposition or other unknown mechanism. The breakdown of rice–wheat synteny due to such transpositions was much greater near the wheat centromeres. Furthermore, the SC rice genes revealed a conserved primordial gene order that gives clues to the origin of rice and wheat chromosomes from a common ancestor through polyploidy, aneuploidy, centromeric fusions, and translocations. Apart from the bin-mapped wheat EST contigs, we also compared 56,298 predicted rice genes with 39,813 wheat EST contigs assembled from 409,765 EST sequences and identified 7,241 SC rice gene homologs of wheat. Based on the conserved colinearity of 1,063 mapped SC rice genes across the bins of individual wheat chromosomes, we predicted the wheat bin location of 6,178 unmapped SC rice gene homologs and validated the location of 213 of these in the telomeric bins of 21 wheat chromosomes with 35.4% initial success. This opens up the possibility of directed mapping of a large number of conserved SC rice gene homologs in wheat. Overall, only 46.4% of these SC genes code for proteins with known functional domains; the remaining 53.6% have unknown function, and hence, represent an important, but yet, under explored category of genes. Electronic supplementary material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   
100.
BackgroundHealthcare workers (HCWs) and ethnic minority groups are at increased risk of COVID-19 infection and adverse outcomes. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is now available for frontline UK HCWs; however, demographic/occupational associations with vaccine uptake in this cohort are unknown. We sought to establish these associations in a large UK hospital workforce.Methods and findingsWe conducted cross-sectional surveillance examining vaccine uptake amongst all staff at University Hospitals of Leicester NHS Trust. We examined proportions of vaccinated staff stratified by demographic factors, occupation, and previous COVID-19 test results (serology/PCR) and used logistic regression to identify predictors of vaccination status after adjustment for confounders. We included 19,044 HCWs; 12,278 (64.5%) had received SARS-CoV-2 vaccination. Compared to White HCWs (70.9% vaccinated), a significantly smaller proportion of ethnic minority HCWs were vaccinated (South Asian, 58.5%; Black, 36.8%; p < 0.001 for both). After adjustment for age, sex, ethnicity, deprivation, occupation, SARS-CoV-2 serology/PCR results, and COVID-19-related work absences, factors found to be negatively associated with vaccine uptake were younger age, female sex, increased deprivation, pregnancy, and belonging to any non-White ethnic group (Black: adjusted odds ratio [aOR] 0.30, 95% CI 0.26–0.34, p < 0.001; South Asian: aOR 0.67, 95% CI 0.62–0.72, p < 0.001). Those who had previously had confirmed COVID-19 (by PCR) were less likely to be vaccinated than those who had tested negative. Limitations include data being from a single centre, lack of data on staff vaccinated outside the hospital system, and that staff may have taken up vaccination following data extraction.ConclusionsEthnic minority HCWs and those from more deprived areas as well as younger staff and female staff are less likely to take up SARS-CoV-2 vaccination. These findings have major implications for the delivery of SARS-CoV-2 vaccination programmes, in HCWs and the wider population, and should inform the national vaccination programme to prevent the disparities of the pandemic from widening.

In a cross-sectional study, Dr. Christopher A. Martin and colleagues investigate factors associated with SARS-CoV-2 vaccine uptake in a multi-ethnic healthcare workforce in UK.  相似文献   
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