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11.
Discriminant analysis was used to differentiate patients with pulmonary tuberculosis (N = 106) from healthy individuals (N = 328) and patients whose treatment was efficient (N = 71) from those whose treatment was inefficient (N = 35). The analysis involved the data on nine polymorphic codominant loci: HP, GC, TF, PI, PGM1, GLO1, C3, ACP1, and ESD. The loci were selected by significance of differences in genotype frequencies between tuberculosis patients and healthy controls (GC, TF, PI, C3, ACP1) or between the two groups of patients differing in treatment efficiency (HP, GC, PI, PGM1, C3, ESD). Discrimination was based on a graphic method of Bayes classification procedure with a single-variate nomograph allowing easy estimation of the a posteriori probabilities for an individual to be classified. The two groups of patients proved to be discriminated sufficiently well (probability of misclassification P err = 0.24), whereas discrimination between tuberculosis patients and healthy individuals was less efficient (P err = 0.33). The method was proposed as a means of predicting the efficiency of treatment in pulmonary tuberculosis. Along with clinical, roentgenological, and laboratory examination, discriminant analysis may be employed as an accessory test in diagnostics of pulmonary tuberculosis, especially when the diagnosis is questionable.  相似文献   
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Heterozygosity at nine genetic loci (PI, TF, PGM1, ACP1, HP, GC, GLO1, C3, and ESD) was analyzed in pulmonary tuberculosis patients with good (group 1, N= 71) and poor (group 2, N= 35) response to treatment. The observed heterozygosities were compared with the expected values, which were calculated from allele frequencies in a control sample of healthy individuals (N= 328 with all but one locus and 78 with ESD) according to Hardy–Weinberg expectations. The analysis showed that the observed heterozygosities g l of patients significantly differed from the expected values h lin the case of four loci (GC, PI, C3, and ACP1). The observed heterozygosity was higher than expected in three cases (PI, C3, and ACP1) and lower then expected (GC) in one case. When data on each individual locus were compared using Fisher's exact test, both groups of patients proved to significantly differ (P F< 0.05) from the control group in the same four loci. No difference in observed heterozygosity was detected between the two groups of patients. The mean expected heterozygosity was h¯= 0.386 ± 0.00674; the mean observed heterozygosity was g¯ = 0.415 ± 0.02 in group 1, g¯ = 0.402 ± 0.026 in group 2, and g¯ = 0.371 ± 0.00955 in the control group. The ttest did not reveal a significant difference between the mean values of expected observed heterozygosities. Heterozygosity at individual loci, rather than mean heterozygosity, was proposed as an integral nonspecific indicator of the genetic control of a disease, because the former directly implicates individual marker loci in the development of a disorder, whereas effects of individual loci may eliminate each other when mean heterozygosity is computed. Based on the results obtained, a genetic control was assumed for the development of the tuberculosis process in the lungs.  相似文献   
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The size of animal populations fluctuates with number of births, rate of immigration, rate of emigration, and number of deaths. For many ungulate populations, adult female survival is the most important factor influencing population growth. Therefore, increased understanding of survival and causes of mortality for adult females is fundamental for conservation and management. The objectives of our study were to quantify survival rates of female elk (Cervus canadensis) and determine cause-specific mortality. We predicted that hunter harvest would be the leading cause of mortality. Further, we predicted that hunters would harvest animals that were in prime age (2–9 yr) and in better condition than elk predated by mountain lions (Puma concolor). From 2015 to 2017, we captured 376 female elk in central Utah, USA. We assessed body size and condition of captured elk, fitted each animal with a global positioning system-collar, and determined cause of death when we received mortality signals. We estimated survival using Kaplan-Meier estimates and Cox proportional hazard models within an Akaike's Information Criterion model selection framework to identify covariates that influenced survival. We analyzed differences in size and condition measurements between harvested elk and predated elk using analysis of variance tests. Our best model indicated consistent survival across years; mean survival was 78.3 ± 3.5% (SE) including hunter harvest and 95.5 ± 1.7% without hunter harvest. In decreasing order of importance, elk mortality occurred from hunter harvest (21.2%), mountain lion predation (3.7%), depredation removal (0.5%), automobile collision (0.3%), disease (0.3%), complications during calving (0.3%), and those characterized as undetermined (1.3%). Neck circumference and body length were negatively associated with survival, suggesting that larger animals in good condition had lower survival as a result of hunter harvest. Individuals that died because of cougar predation were smaller and had less loin muscle than the average animal. Hunters removed large, healthy, prime-aged females, individuals that likely have a greater effect on population growth than elk lost to other predators. If the proportion of larger, healthy females in the population begins to decline, hunting practices may require adjustment because hunters may be removing individuals with the greatest reproductive value. © 2021 The Wildlife Society.  相似文献   
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The IgG Fc glycans strongly influence the Fcγ receptor interactions and Fc-mediated effector mechanisms. Changes in the structure of IgG glycans are associated with various diseases, such as infections and autoimmunity. However, the possible role of Fc glycans in tumor immunity is not yet fully understood. The aim of this study was to profile the Fc N-glycans of IgG samples from patients with gastric cancer (n = 80) and controls (n = 51) using LC-ESI-MS method to correlate the findings with stage of cancer and patients survival. Analysis of 32 different IgG N-glycans revealed significant increase of agalactosylated (GnGnF, GnGn(bi)F), and decrease of galactosylated (AGn(bi), AGn(bi)F, AA(bi), AAF) and monosialylated IgG glycoforms (NaAF, NaA(bi)) in cancer patients. A statistically significant increase of Fc fucosylation was observed in tumor stage II and III whereas reverse changes were found for the presence of bisecting GlcNAc. Higher level of fully sialylated glycans and elevated expression of glycans with bisecting GlcNAc were associated with better survival rate. Our findings provide the first evidence that the changes in Fc glycan profile may predict the survival of patients with gastric cancer. Cancer stage-dependent changes in Fc fucosylation and the bisecting N-acteylglucosamine expression as well as an association of several IgG glycoforms with the survival suggest that IgG glycosylation is related to pathogenesis of cancer and progression of the disease.  相似文献   
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The stereochemistry of all four stereoisomers of brivaracetam was determined using vibrational circular dichroism (VCD) spectroscopy. By comparing experimentally obtained VCD spectra and computationally simulated ones, the absolute configurations can be confidently assigned without prior knowledge of their relative stereochemistry. Neither the corrected mean absolute errors analysis of the nuclear magnetic resonance (NMR) data, nor the matching of experimental and calculated infrared spectra allowed the diastereoisomers to be distinguished. VCD spectroscopy itself suffices to establish the absolute configurations of all diastereoisomers. The relative stereochemistry could also be statistically confirmed by matching experimental and computed NMR spectra using the CP3 algorithm. The combination of VCD and NMR is recommended for molecules bearing more than one chiral center, as the relative configurations obtained from NMR serve as an independent check for those established with VCD. Analysis of the calculated VCD spectra reveals that the localized NH2 scissoring mode at around 1600 cm‐1 is characteristic for intramolecular hydrogen bonding, while the orientation of the ethyl group is reflected by the delocalized modes between 1150 and 1050 cm‐1. Chirality 28:215–225, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
17.
Targeting of green fluorescent protein expression to the cell surface.   总被引:2,自引:0,他引:2  
We have previously reported on GPI-anchored fusion proteins that bind radioactive isotopes. We targeted their expression to the cell surface to obtain a marker protein detectable by nuclear and optical imaging (1, 2). Here we suggest a novel approach for targeting a model protein (GFP) to the exoplasmic surface of the plasma membrane. An expression vector (pcPEP-GFP) was constructed containing GFP cDNA fused with the fragment encoding the N-terminal cytoplasmic domain and signal peptide/membrane anchoring domain of the rabbit neutral endopeptidase (PEP-GFP). Flow cytometry showed green fluorescence in 45% of cells transfected with GFP and in 34% of cells transfected with PEP-GFP (24 h after transfection). Fluorescence microscopy of fixed cells stained with rhodaminated anti-GFP antibodies showed positive reaction only in the case of PEP-GFP-transfected cells indicating cell-surface expression. The PEP-GFP fusion protein was identified as a component of the light microsomal and Golgi fractions by immunoblotting.  相似文献   
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A novel method for the determination of the three-dimensional (3D) structure of oligosaccharides in the solid state using experimental 13C NMR data is presented. The approach employs this information, combined with 13C chemical shift surfaces (CSSs) for the glycosidic bond carbons in the generation of NMR pseudopotential energy functions suitable for use as constraints in molecular modeling simulations. Application of the method to trehalose, cellobiose, and cellotetraose produces 3D models that agree remarkably well with the reported X-ray structures, with phi and psi dihedral angles that are within 10 degrees from the ones observed in the crystals. The usefulness of the approach is further demonstrated in the determination of the 3D structure of the cellohexaose, an hexasaccharide for which no X-ray data has been reported, as well as in the generation of accurate structural models for cellulose II and amylose V6.  相似文献   
20.
The formation of metal-containing Ag-mercaptoethanol (-Ag-S(R)-)(n) complexes on DNA chain scaffold was studied by UV spectroscopy, zeta potential measurement, and fluorescence and transmission electron microscopies. Experimental results made clear the mechanism of DNA mineralization and compaction, according to which intercalation of silver cations into DNA scaffold and further formation of (-Ag-S(R)-)(n) oligomeric complexes on DNA induce efficient DNA chain compaction by terminal Ag(+) cations. By transmission electron microscopy the formation of fiber-like DNA-templated nanostructures was observed. DNA-Ag-thiol complexes are promising for DNA-templated engineering of hybrid 1D nanostructures with adjustable chemical functionalities by choosing appropriate thiol ligand.  相似文献   
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