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Girish KR  Usha R 《Virus research》2005,108(1-2):167-176
The complete nucleotide sequences of two soybean-infecting begomoviruses have been determined from central and southern parts of India. Sequence analyses show that the isolate from central India is a strain of Mungbean yellow mosaic India virus (MYMIV) and the southern Indian isolate is a strain of Mungbean yellow mosaic virus (MYMV). Multiple DNA B components could be detected with the soybean strain of Mungbean yellow mosaic virus species. The nucleotide sequence similarity between the DNA A components of the two isolates is higher (82%) than that between the corresponding DNA B components (71%). Analyses of the common region of the genomic components of these two virus isolates indicate considerable divergence in the origin of replication (ori), which did not impair their infectivity as demonstrated for the central Indian isolate by agroinfection with partial tandem repeats (PTRs) of the genomic components. Detailed sequence and phylogenetic analyses reveal the distribution and possible recombination events among legume-infecting begomoviruses from South-East Asia.  相似文献   
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Obesity and the risk of heart failure   总被引:1,自引:0,他引:1  
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Background  

CD4+ T lymphocyte (CD4) cell count testing is the standard method for determining eligibility for antiretroviral therapy (ART), but is not widely available in sub-Saharan Africa. Total lymphocyte counts (TLCs) have not proven sufficiently accurate in identifying subjects with low CD4 counts. We developed clinical algorithms using TLCs, hemoglobin (Hb), and body mass index (BMI) to identify patients who require ART.  相似文献   
27.
This study simulates a multi-pinhole single-photon emission computed tomography (SPECT) system using the Monte Carlo method, and investigates different multi-pinhole designs for quantitative mouse brain imaging. Prior approaches investigating multi-pinhole SPECT were not often optimal, as the number and geometrical arrangement of pinholes were usually chosen empirically. The present study seeks to optimize the number of pinholes for a given pinhole arrangement, and also for the specific application of quantitative neuroreceptor binding in the mouse brain. An analytical Monte Carlo simulation based method was used to generate the projection data for various count levels. A three-dimensional ordered-subsets expectation-maximization algorithm was developed and used to reconstruct the images, incorporating a realistic pinhole model for resolution recovery and noise reduction. Although artefacts arising from overlapping projections could be a major problem in multi-pinhole reconstruction, the cold-rod phantom study showed minimal loss of spatial resolution in multi-pinhole systems, compared to a single-pinhole system with the same pinhole diameter. A quantitative study of neuroreceptor binding sites using a mouse brain phantom and low activity (37 MBq) showed that the multi-pinhole system outperformed the single-pinhole system by maintaining the mean and lowering the variance in the measured uptake ratio. Multi-pinhole collimation can be used to reduce the injected dose and thereby reduce the radiation exposure to the animal. Results also suggest that the nine-pinhole configuration shown in this paper is a good choice for mouse brain imaging.  相似文献   
28.
The persistence of Bordetella pertussis and B. parapertussis within vaccinated populations and the reemergence of associated disease highlight the need to better understand protective immunity. The present study examined host immunity to bordetellae and addressed potential concerns about the mouse model by using a comparative approach including the closely related mouse pathogen B. bronchiseptica. As previously observed with B. pertussis, all three organisms persisted throughout the respiratory tracts of B-cell-deficient mice, indicating that B cells are required for bacterial clearance. However, adoptively transferred antibodies rapidly cleared B. bronchiseptica but not human pathogens. These results obtained with the mouse model are consistent with human clinical observations, including the lack of correlation between antibody titers and protection, as well as the limited efficacy of intravenous immunoglobulin treatments against human disease. Together, this evidence suggests that the mouse model accurately reflects substantial differences between immunities to these organisms. Although both B. pertussis and B. parapertussis are more closely related to B. bronchiseptica than they are to each other, they share the ability to resist rapid clearance from the lower respiratory tract by adoptively transferred antibodies, an adaptation that correlates with their emergence as human pathogens that circulate within vaccinated populations.  相似文献   
29.
We have sequenced the genes encoding the inner capsid protein VP6 and the nonstructural proteins NSP1 and NSP4 of the Indian neonatal serotype P8[11]G9 human/bovine reassortant candidate vaccine rotavirus strain 116E. These three genes share a high degree of sequence and deduced amino acid homology with human prototype strain Wa. Our results confirm and extend those of previous RNA-RNA hybridization studies which suggested that these genes are of human origin, and will facilitate examination of the host immune response to 116E induced by natural infection and vaccination. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
30.

Background

Recent studies have suggested that removing foods from the diet to manage atopic dermatitis (AD), based on positive allergy test results, may lead to immediate allergic reactions on reintroduction of that food.

Objective

To examine the frequency of oral food challenge (OFC) failures among foods removed from the diet as suspected AD triggers, focusing on the 5 major food allergens in the United States.

Methods

OFCs to egg, milk, peanut, soy, and wheat, performed from 2008 to 2014, at a children's hospital's allergy clinics, were reviewed. OFCs were offered based on history and laboratory values. Reasons for food avoidance were classified as food allergy (IgE-mediated reaction occurring within 2 hours); sensitization only (lack of introduction because of positive test results); and removal because of test results during AD evaluation.

Results

There were 442 OFCs performed, with 89 failures (20.1%). Reasons for OFCs included a history of food allergy (320 of 442 [72.4%]), food sensitization without any introduction (77 of 442 [17.4%]), and AD (45 of 442 [10.2%]). OFC failures among those who had food allergy (70 of 320 [21.9%]), sensitization only (13 of 77 [16.9%]), and suspected AD trigger (6 of 45 [13.3%]) did not significantly differ (P?=?.63). Wheat was more likely to be avoided than the other 4 foods for AD concerns (P < .001).

Conclusion

The frequency of OFC failure among those who removed foods suspected as AD triggers was 13.3%, indicating a loss of tolerance. Restriction of foods to manage AD must be done with caution and close monitoring.  相似文献   
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