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21.
Tomographic phase microscopy 总被引:1,自引:0,他引:1
We report a technique for quantitative three-dimensional (3D) mapping of refractive index in live cells and tissues using a phase-shifting laser interferometric microscope with variable illumination angle. We demonstrate tomographic imaging of cells and multicellular organisms, and time-dependent changes in cell structure. Our results will permit quantitative characterization of specimen-induced aberrations in high-resolution microscopy and have multiple applications in tissue light scattering. 相似文献
22.
Deng Chen Hong Hu Wenhui He Shimei Zhang Mengxi Tang Shikun Xiang Caiyun Liu Xuan Cai Ahmed Hendy Muhammad Kamran Hao Liu Lu Zheng Junbing Huang Xiao-Lin Chen Junjie Xing 《Molecular Plant Pathology》2022,23(1):133-147
Endocytosis plays key roles during infection of plant-pathogenic fungi, but its regulatory mechanisms are still largely unknown. Here, we identified a putative endocytosis-related gene, PAL1, which was highly expressed in appressorium of Magnaporthe oryzae, and was found to be important for appressorium formation and maturation. Deletion of PAL1 significantly reduced the virulence of M. oryzae due to defects in appressorial penetration and invasive growth in host cells. The Pal1 protein interacted and colocalized with the endocytosis protein Sla1, suggesting it is involved in endocytosis. The Δpal1 mutant was significantly reduced in appressorium formation, which was recovered by adding exogenous cAMP and 3-isobutyl-1-methylxanthine (IBMX). Moreover, the phosphorylation level of Pmk1 in Δpal1 was also reduced, suggesting Pal1 functions upstream of both the cAMP and Pmk1 signalling pathways. As a consequence, the utilization of glycogen and lipid, appressorial autophagy, actin ring formation, localization of septin proteins, as well as turgor accumulation were all affected in the Δpal1 mutant. Taken together, Pal1 regulates cAMP and the Pmk1 signalling pathway for appressorium formation and maturation to facilitate infection of M. oryzae. 相似文献
23.
Rakhshan Kamran Dalouchi Fereshteh Sharifiaghdam Zeynab Safaei Atlasi Jahanshahi Fatemeh Azizi Yaser 《International journal of peptide research and therapeutics》2022,28(4):1-12
International Journal of Peptide Research and Therapeutics - Fibroblast growth factor 21 (FGF21) is a metabolic regulator with a wide range of biological functions. Although previous studies have... 相似文献
24.
Faran Muhammad Farooq Muhammad Rehman Abdul Nawaz Ahmad Saleem Muhammad Kamran Ali Nauman Siddique Kadambot H. M. 《Plant and Soil》2019,437(1-2):195-213
Plant and Soil - Abiotic stresses are threatening wheat productivity across the globe, which is often associated with nutrient deficiencies. Zinc (Zn) is involved in many physiological processes of... 相似文献
25.
The emergence of numerous genome projects has made the experimental classification of the protein localization almost impossible due to the exponential increase in the number of protein samples. However, most of the applications are merely developed for single-plex and completely ignored the presence of one protein at two or more locations in a cell. In this regard, few attempts were carried out to target Multi-label protein localizations; consequently, undesirable accuracies are achieved. This paper presents a novel approach, in which a discrete feature extraction method is fused with physicochemical properties of amino acids by using Chou's general form of Pseudo Amino Acid Composition. The technique is tested on two benchmark datasets namely: Gpos-mploc and Virus-mPLoc. The empirical results demonstrated that the proposed method yields better results via two examined classifiers i.e. ML-KNN and Rank-SVM. It is established that the proposed model has improved values in all performance measures considered for the comparison. 相似文献
26.
27.
Background
We set out to describe the risk of hospitalization from heart disease, stroke, and diabetes among persons born in India, all foreign-born persons, and U.S.-born persons residing in New York City.Methods
We examined billing records of 1,083,817 persons hospitalized in New York City during the year 2000. The zip code of each patient's residence was linked to corresponding data from the 2000 U.S. Census to obtain covariates not present in the billing records. Using logistic models, we evaluated the risk of hospitalization for heart disease, stroke and diabetes by country of origin.Results
After controlling for covariates, Indian-born persons are at similar risk of hospitalization for heart disease (RR = 1.02, 95% confidence interval 1.02, 1.03), stroke (RR = 1.00, 95% confidence interval, 0.99, 1.01), and diabetes mellitus (RR = 0.96 95% confidence interval 0.94, 0.97) as native-born persons. However, Indian-born persons are more likely to be hospitalized for these diseases than other foreign-born persons. For instance, the risk of hospitalization for heart disease among foreign-born persons is 0.70 (95% confidence interval 0.67, 0.72) and the risk of hospitalization for diabetes is 0.39 (95% confidence interval 0.37, 0.42) relative to native-born persons.Conclusions
South Asians have considerably lower rates of hospitalization in New York than reported in countries with national health systems. Access may play a role. Clinicians working in immigrant settings should nonetheless maintain a higher vigilance for these conditions among Indian-born persons than among other foreign-born populations. 相似文献28.
Bae JH Rubini M Jung G Wiegand G Seifert MH Azim MK Kim JS Zumbusch A Holak TA Moroder L Huber R Budisa N 《Journal of molecular biology》2003,328(5):1071-1081
Much effort has been dedicated to the design of significantly red shifted variants of the green fluorescent protein (GFP) from Aequoria victora (av). These approaches have been based on classical engineering with the 20 canonical amino acids. We report here an expansion of these efforts by incorporation of an amino substituted variant of tryptophan into the "cyan" GFP mutant, which turned it into a "gold" variant. This variant possesses a red shift in emission unprecedented for any avFP, similar to "red" FPs, but with enhanced stability and a very low aggregation tendency. An increasing number of non-natural amino acids are available for chromophore redesign (by engineering of the genetic code) and enable new general strategies to generate novel classes of tailor-made GFP proteins. 相似文献
29.
Multiple,independently regulated pathways of cholesterol transport across the intestinal epithelial cells 总被引:3,自引:0,他引:3
The present study provides a new understanding about the mechanisms involved in cholesterol absorption by the intestinal cells. Contrary to general belief, our data show that newly absorbed cholesterol is neither immediately available for secretion with apoB lipoproteins nor exclusively secreted as part of chylomicrons. Based on our data, cholesterol transport by enterocytes can be broadly classified into two independently modulated, apoB-dependent and -independent, pathways. Cholesterol secretion by the apoB-dependent pathway is induced by oleic acid, is repressed by microsomal triglyceride transfer protein inhibitors, and occurs only with larger apoB-containing lipoproteins. ApoB-independent pathways do not require microsomal triglyceride transfer protein and involve efflux mediated by ABCA1, high density lipoprotein assembly, and possibly other unknown mechanisms. There are at least two different metabolic pools of cholesterol. The newly absorbed and pre-absorbed cholesterol are preferentially secreted via apoB-independent and apoB-dependent pathways, respectively. In contrast to compartmentalization for secretion, these two metabolic pools are equally accessible for cellular esterification. The esterified cholesterol is mainly secreted by the apoB-dependent pathway, whereas both the pathways are involved in the secretion of free cholesterol. Thus, enterocytes transport exogenous cholesterol by several independently regulated pathways raising the possibility that targeting of apoB-independent pathways may result in selective inhibition of cholesterol transport without affecting triglyceride transport. 相似文献
30.
The ribosomal protein RpL14 gene has been characterized in several species, including, human, rat and fruit fly. Haploinsufficiency for the gene causes the Minute phenotype in Drosophila, and it has been proposed as a regulator in the tumorigenic pathway in human. Several features concerning the gene structure have been studied, and some of these differ between human/rat and Drosophila. To address functional and evolutionary questions about these differences we have isolated and sequenced a cDNA and a genomic clone covering the RpL14 gene from the pufferfish Takifugu rubripes (Fugu). The Fugu RpL14 gene is approximately 2 Kb, with 5 introns, and encodes a protein of 137 amino acids. The protein contains a KOW-motif and a nuclear localization signal, which are conserved among a wide range of RPL14 proteins. On the other hand, a variable amino acid (alanine) repeat observed in human is missing in Takifugu rubripes, and the protein is shorter than its mammalian counterparts. Compared with human, the RpL14 gene in Fugu contains introns localized at identical positions in the gene, and most of them are shorter. A comparison of the RpL14 gene structure from a broad range of organisms indicates that both loss and gain of introns have occurred during the evolution of the gene. 相似文献