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81.
This article examines the influence of nutritional status on the emergence of deciduous dentition in a cross-sectional sample of 510 rural Rajput children from the Jubbal and Kotkhai Tehsils, Shimla District, Himachal Pradesh, India. The nutritional status of each child was evaluated using Z-scores of height/supine length-for-age (HAZ), weight-for-age (WAZ), and weight-for-height (WHZ). The effects of sex and side on deciduous dental emergence were not statistically significant. Partial correlation indicates that the number of emerged teeth (T) was more strongly correlated with height than with other anthropometric variables. In most age groups, the stunted boys and girls (HAZ <-2) had fewer emerged teeth than nonstunted age peers (HAZ >-2). The mean T in underweight children was also less than that of the normal children, with a few exceptions. The stunted children have a significantly greater likelihood of delayed emergence of deciduous dentition. Measures of linear growth status are more closely related to dental development than measures of growth in mass. The findings indicate that even moderate undernutrition can delay deciduous tooth emergence. 相似文献
82.
The chickpea (Cicer arietinum L.) is a self-pollinated grain legume with cleistogamous flowers. A spontaneous open-flower mutant, designated OFM-3, was identified in which reproductive organs were not enclosed by the keel petals and thus remained exposed. All 10 stamens in this mutant were free, whereas these are in diadelphous (9 fused + 1 free) condition in normal chickpea flowers. A large number of pods (73%) remained unfilled (empty) in OFM-3, though its pollen fertility was as high as the standard cultivars. The open-flower trait was found to be recessive and controlled by a single gene. OFM-3 was crossed with earlier reported open-flower mutants, ICC 16341 and ICC 16129, to establish trait relationships of genes controlling open flower traits in these mutants. It was found that each of these mutants has a unique gene for open flower trait. The genes controlling open flower trait in ICC 16341, ICC 16129, and OFM-3 were designated ofl-1, ofl-2, and ofl-3, respectively. Breeding lines with open flower trait and higher percentage of filled pods have been developed from the progenies of the crosses of OFM-3 with normal-flowered lines. The open flower trait offers opportunity for exploring hybrid technology in the chickpea. 相似文献
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85.
Choudhary S Gaur R Gupta S 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(8):1449-1462
Well-saturated linkage maps especially those based on expressed sequence tag (EST)-derived genic molecular markers (GMMs)
are a pre-requisite for molecular breeding. This is especially true in important legumes such as chickpea where few simple
sequence repeats (SSR) and even fewer GMM-based maps have been developed. Therefore, in this study, 2,496 ESTs were generated
from chickpea seeds and utilized for the development of 487 novel EST-derived functional markers which included 125 EST-SSRs,
151 intron targeted primers (ITPs), 109 expressed sequence tag polymorphisms (ESTPs), and 102 single nucleotide polymorphisms
(SNPs). Whereas EST-SSRs, ITPs, and ESTPs were developed by in silico analysis of the developed EST sequences, SNPs were identified
by allele resequencing and their genotyping was performed using the Illumina GoldenGate Assay. Parental polymorphism was analyzed
between C. arietinum ICC4958 and C. reticulatum PI489777, parents of the reference chickpea mapping population, using a total of 872 markers: 487 new gene-based markers
developed in this study along with 385 previously published markers, of which 318 (36.5%) were found to be polymorphic and
were used for genotyping. The genotypic data were integrated with the previously published data of 108 markers and an advanced
linkage map was generated that contained 406 loci distributed on eight linkage groups that spanned 1,497.7 cM. The average
marker density was 3.68 cM and the average number of markers per LG was 50.8. Among the mapped markers, 303 new genomic locations
were defined that included 177 gene-based and 126 gSSRs (genomic SSRs) thereby producing the most advanced gene-rich map of
chickpea solely based on co-dominant markers. 相似文献
86.
Wang L Prozorov T Palo PE Liu X Vaknin D Prozorov R Mallapragada S Nilsen-Hamilton M 《Biomacromolecules》2012,13(1):98-105
Highly ordered mineralized structures created by living organisms are often hierarchical in structure with fundamental structural elements at nanometer scales. Proteins have been found responsible for forming many of these structures, but the mechanisms by which these biomineralization proteins function are generally poorly understood. To better understand its role in biomineralization, the magnetotactic bacterial protein, Mms6, which promotes the formation in vitro of superparamagnetic magnetite nanoparticles of uniform size and shape, was studied for its structure and function. Mms6 is shown to have two phases of iron binding: one high affinity and stoichiometric and the other low affinity, high capacity, and cooperative with respect to iron. The protein is amphipathic with a hydrophobic N-terminal domain and hydrophilic C-terminal domain. It self-assembles to form a micelle, with most particles consisting of 20-40 monomers, with the hydrophilic C-termini exposed on the outside. Studies of proteins with mutated C-terminal domains show that the C-terminal domain contributes to the stability of this multisubunit particle and binds iron by a mechanism that is sensitive to the arrangement of carboxyl/hydroxyl groups in this domain. 相似文献
87.
K Parthasarathy H Lu W Surya A Vararattanavech K Pervushin J Torres 《Protein expression and purification》2012,85(1):133-141
Coronavirus envelope (E) proteins are short (~100 residues) polypeptides that contain at least one transmembrane (TM) domain and a cluster of 2-3 juxtamembrane cysteines. These proteins are involved in viral morphogenesis and tropism, and their absence leads in some cases to aberrant virions, or to viral attenuation. In common to other viroporins, coronavirus envelope proteins increase membrane permeability to ions. Although an NMR-based model for the TM domain of the E protein in the severe acute respiratory syndrome virus (SARS-CoV E) has been reported, structural data and biophysical studies of full length E proteins are not available because efficient expression and purification methods for these proteins are lacking. Herein we have used a novel fusion protein consisting of a modified β-barrel to purify both wild type and cysteine-less mutants of two representatives of coronavirus E proteins: the shortest (76 residues), from SARS-CoV E, and one of the longest (109 residues), from the infectious bronchitis virus (IBV E). The fusion construct was subsequently cleaved with cyanogen bromide and all polypeptides were obtained with high purity. This is an approach that can be used in other difficult hydrophobic peptides. 相似文献
88.
Background
To determine the association of the A55T and K153R polymorphisms of the Myostatin gene with obesity, abdominal obesity and lean body mass (LBM) in Asian Indians in north India.Materials and Methods
A total of 335 subjects (238 men and 97 women) were assessed for anthropometry, % body fat (BF), LBM and biochemical parameters. Associations of Myostatin gene polymorphisms were evaluated with anthropometric, body composition and biochemical parameters. In A55T polymorphism, BMI (p = 0.04), suprailiac skinfold (p = 0.05), total skinfold (p = 0.008), %BF (p = 0.002) and total fat mass (p = 0.003) were highest and % LBM (p = 0.03) and total LBM (Kg) were lowest (p = 0.04) in subjects with Thr/Thr genotype as compared to other genotypes. Association analysis of K153R polymorphism showed that subjects with R/R genotype had significantly higher BMI (p = 0.05), waist circumference (p = 0.04), %BF (p = 0.04) and total fat mass (p = 0.03), and lower %LBM (p = 0.02) and total LBM [(Kg), (p = 0.04)] as compared to other genotypes. Using a multivariate logistic regression model after adjusting for age and sex, subjects with Thr/Thr genotype of A55T showed high risk for high %BF (OR, 3.92, 95% Cl: 2.61–12.41), truncal subcutaneous adiposity (OR, 2.9, 95% Cl: 1.57–6.60)] and low LBM (OR, 0.64, 95% CI: 0.33–0.89) whereas R/R genotype of K153R showed high risk of obesity (BMI; OR, 3.2, 95% CI: 1.2–12.9; %BF, OR, 3.6, 95% CI: 1.04–12.4), abdominal obesity (OR, 2.12, 95% CI: 2.71–14.23) and low LBM (OR, 0.61, 95% CI: 0.29–0.79).Conclusions/Significance
We report that variants of Myostatin gene predispose to obesity, abdominal obesity and low lean body mass in Asian Indians in north India. 相似文献89.
We propose a flexible and identifiable version of the 2-groups model, motivated by hierarchical Bayes considerations, that features an empirical null and a semiparametric mixture model for the nonnull cases. We use a computationally efficient predictive recursion (PR) marginal likelihood procedure to estimate the model parameters, even the nonparametric mixing distribution. This leads to a nonparametric empirical Bayes testing procedure, which we call PRtest, based on thresholding the estimated local false discovery rates. Simulations and real data examples demonstrate that, compared to existing approaches, PRtest's careful handling of the nonnull density can give a much better fit in the tails of the mixture distribution which, in turn, can lead to more realistic conclusions. 相似文献
90.
S Ramachandran A Venugopal S K R G S Charles D G NS Chandran A Mullassari MR Pillai CC Kartha 《Proteomics》2012,12(18):2808-2821
Hyperglycemia is widely recognized to be a potent stimulator of monocyte activity, which is a crucial event in the pathogenesis of atherosclerosis. We analyzed the monocyte proteome for potential markers that would enhance the ability to screen for early inflammatory status in Type 2 diabetes mellitus (T2DM), using proteomic technologies. Monocytic cells (THP-1) were primed with high glucose (HG), their protein profiles were analyzed using 2DE and the downregulated differentially expressed spots were identified using MALDI TOF/MS. We selected five proteins that were secretory in function with the help of bioinformatic programs. A predominantly downregulated protein identified as cyclophilin A (sequence coverage 98%) was further validated by immunoblotting experiments. The cellular mRNA levels of cyclophilin A in various HG-primed cells were studied using qRT-PCR assays and it was observed to decrease in a dose-dependent manner. LC-ESI-MS was used to identify this protein in the conditioned media of HG-primed cells and confirmed by Western blotting as well as ELISA. Cyclophilin A was also detected in the plasma of patients with diabetes. We conclude that cyclophilin A is secreted by monocytes in response to HG. Given the paracrine and autocrine actions of cyclophilin A, the secreted immunophilin could be significant for progression of atherosclerosis in type 2 diabetes. Our study also provides evidence that analysis of monocyte secretome is a viable strategy for identifying candidate plasma markers in diabetes. 相似文献