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921.
Usha Ramakrishnan Amanda Stinger Ann M. DiGirolamo Reynaldo Martorell Lynnette M. Neufeld Juan A. Rivera Lourdes Schnaas Aryeh D. Stein Meng Wang 《PloS one》2015,10(8)
Objective
We evaluated the effects of prenatal docosahexaenoic acid (DHA) supplementation on offspring development at 18 months of age.Design
Randomized placebo double-blind controlled trial.Settings
Cuernavaca, Mexico.Participants and Methods
We followed up offspring (n = 730; 75% of the birth cohort) of women in Mexico who participated in a trial of DHA supplementation during the latter half of pregnancy. We assessed the effect of the intervention on child development and the potential modifying effects of gravidity, gender, SES, and quality of the home environment.Interventions or Main Exposures
400 mg/day of algal DHA.Outcome Measures
Child development at 18 months of age measured using the Spanish version of the Bayley Scales of Infant Development-II. We calculated standardized psychomotor and mental development indices, and behavior rating scale scores.Results
Intent-to-treat differences (DHA-control) were: Psychomotor Developmental Index -0.90 (95% CI: -2.35, 0.56), Mental Developmental Index -0.26 (95% CI: -1.63, 1.10) and Behavior Rating Scale -0.01 (95% CI: -0.95, 0.94). Prenatal DHA intake attenuated the positive association between home environment and psychomotor development index observed in the control group (p for interaction = 0.03) suggesting potential benefits for children living in home environments characterized by reduced caregiver interactions and opportunities for early childhood stimulation.Conclusions
Prenatal DHA supplementation in a population with low intakes of DHA had no effects on offspring development at 18 months of age although there may be some benefit for infants from poor quality home environments.Trial Registration
Clinicaltrials.gov NCT00646360 相似文献922.
923.
An essential role of the basal body protein SAS‐6 in Plasmodium male gamete development and malaria transmission 下载免费PDF全文
Sara R. Marques Chandra Ramakrishnan Raffaella Carzaniga Andrew M. Blagborough Michael J. Delves Arthur M. Talman Robert E. Sinden 《Cellular microbiology》2015,17(2):191-206
Gametocytes are the sole Plasmodium parasite stages that infect mosquitoes; therefore development of functional gametes is required for malaria transmission. Flagellum assembly of the Plasmodium male gamete differs from that of most other eukaryotes in that it is intracytoplasmic but retains a key conserved feature: axonemes assemble from basal bodies. The centriole/basal body protein SAS‐6 normally regulates assembly and duplication of these organelles and its depletion causes severe flagellar/ciliary abnormalities in a diverse array of eukaryotes. Since basal body and flagellum assembly are intimately coupled to male gamete development in Plasmodium, we hypothesized that SAS‐6 disruption may cause gametogenesis defects and perturb transmission. We show that Plasmodium berghei sas6 knockouts display severely abnormal male gametogenesis presenting reduced basal body numbers, axonemal assembly defects and abnormal nuclear allocation. The defects in gametogenesis reduce fertilization and render Pbsas6 knockouts less infectious to mosquitoes. Additionally, we show that lack of Pbsas6 blocks transmission from mosquito to vertebrate host, revealing an additional yet undefined role in ookinete to sporulating oocysts transition. These findings underscore the vulnerability of the basal body/SAS‐6 to malaria transmission blocking interventions. 相似文献
924.
Shivani?Nagar V.?P.?SinghEmail author Ajay?Arora Rajkumar?Dhakar Shiv?Ramakrishnan 《Acta Physiologiae Plantarum》2015,37(12):257
Terminal heat stress is one of the limiting factors in wheat production and it is expected to rise under present scenario of climate change. The present study was conducted to evaluate the performance of 40 wheat genotypes under terminal heat stress conditions based on eight physiological traits. The plants were sown late (i.e. on 5th January) to expose them terminal heat stress. The genotypes were evaluated using multivariate analysis viz. Ward’s method of hierarchical clusters analysis, discriminant analysis and principle component analysis. The genotypes were categorized into three groups namely tolerant, intermediate and sensitive. Tolerant genotypes like DBW 14, RAJ 3765, HD 2643 and HALNA performed physiologically better in terms of higher membrane stability index (MSI), chlorophyll content, photosynthesis rate (Pn), harvest index under heat stress conditions. Genotypes HD 2987, SHANGHAI, HD 2402 and WH 730 were found to be heat sensitive. Physiological traits like MSI, SPAD value, Fv/Fm ratio and Pn were found to be most important contributor in grouping of genotypes and showed positive correlations (r) of 0.73, 0.47, 0.41 and 0.39 with grain yield, respectively, which is significant at p < 0.05. The large genetic diversity was found among the genotypes based on physiological traits. These genotypes can be utilized in wheat improvement programme for heat tolerance. 相似文献
925.
Small mammal dispersal is strongly affected by geographical barriers. However, commensal small mammals may be passively transported over large distances and strong barriers by humans (often with agricultural products). This pattern should be especially apparent in topographically complex landscapes, such as mountain ranges, where valleys and/or peaks can limit dispersal of less vagile species. We predict that commensal species would have lower genetic differentiation and higher migration rates than related non-commensals in such landscapes. We contrasted population genetic differentiation in two sympatric Rattus species (R. satarae and R. rattus) in the Western Ghats mountains in southern India. We sampled rats from villages and adjacent forests in seven locations (20–640 km apart). Capture-based statistics confirmed that R. rattus is abundant in human settlements in this region, whereas R. satarae is non-commensal and found mostly in forests. Population structure analyses using ~970-bp mitochondrial control region and 17 microsatellite loci revealed higher differentiation for the non-commensal species (R. satarae F-statistics=0.420, 0.065, R. rattus F-statistics=0.195, 0.034; mitochondrial DNA, microsatellites, respectively). Genetic clustering analyses confirm that clusters in R. satarae are more distinct and less admixed than those in R. rattus. R. satarae shows higher slope for isolation-by-distance compared with R. rattus. Although mode of migration estimates do not strongly suggest higher rates in R. rattus than in R. satarae, they indicate that migration over long distances could still be higher in R. rattus. We suggest that association with humans could drive the observed pattern of differentiation in the commensal R. rattus, consequently impacting not only their dispersal abilities, but also their evolutionary trajectories. 相似文献
926.
Venkata Ravi Gutlapalli Aparna Sykam Anuraj Nayarisseri Sujai Suneetha Lavanya M Suneetha 《Bioinformation》2015,11(12):517-524
Mycobacterium tuberculosis is known to be associated with several autoimmune diseases such as systemic lupus erythematous,
rheumatoid arthritis and multiple sclerosis. This is attributed to sequence similarity between virulent factors and human proteins.
Therefore, it is of interest to identify such regions in the virulent factors to assess potential autoimmune related information. M.
tb specific virulent factors were downloaded from the VFDB database and its human homologs were identified using the sequence
comparison search tool BLASTP. Both virulent proteins and their corresponding human homologs were further scanned for
epitopes (B cell and HLA class I and II allele specific) using prediction programs (BCPRED and NETMHC). Data shows the
presence of matching 22 B-cell, 79 HLA class II and 16 HLA class I specific predicted epitopes in these virulent factors having
human homologs. A known peptide (HAFYLQYKNVKVDFA) associated with autoimmune atopic dermatitis is shown in the
superoxide dismutase homolog structures of the bacterium (PDB ID: 1IDS) and human (PDB ID: 2QKC). This data provides insight
into the understanding of infection-associated auto-immunity 相似文献
927.
Ordinarily, RIP-induced erg-3 mutant Neurospora crassa ascospores and their erg(+) siblings do not differ in stability during long-term storage. Consequently, the frequency of RIP-induced erg-3 mutants remains about constant regardless of the time that has elapsed between ascospore harvest and germination. We found, however, that RIP-induced erg-3 mutants were apparently selectively lost with time from among the ascospores stored from a cross with the wild-isolated Carrefour Mme. Gras strain from Haiti. The Haitian strain was also found to exert a dominant suppression of meiotic silencing by unpaired DNA. Similar loss of RIP-induced erg-3 mutant ascospores was seen among the stored ascospores from a subset of crosses heterozygous for the semi-dominant Sad-1 or Sad-2 suppressors of meiotic silencing. Our results suggest that crosses suppressed in meiotic silencing can compromise the stability during storage of ascospores that inherit RIP-induced mutations. 相似文献
928.
929.
Malhi RS Trask JS Shattuck M Johnson J Chakraborty D Kanthaswamy S Ramakrishnan U Smith DG 《American journal of primatology》2011,73(10):1031-1040
The development of DNA markers is becoming increasingly useful in the field of primatology for studies on paternity, population history, and biomedical research. In this study, we determine the efficacy of using cross-species amplification to identify single nucleotide polymorphisms (SNPs) in closely related species. The DNA of 93 individuals representing seven Old World Monkey species was analyzed to identify SNPs using cross-species amplification and genotyping. The loci genotyped were 653 SNPs identified and validated in rhesus macaques. Of the 653 loci analyzed, 27% were estimated to be polymorphic in the samples studied. SNPs identified at the same locus among different species (coincident SNPs) were found in six of the seven species studied with longtail macaques exhibiting the highest number of coincident SNPs (84). The distribution of coincident SNPs among species is not biased based on proximity to genes in the samples studied. In addition, the frequency of coincident SNPs is not consistent with expectations based on their phylogenetic relationships. This study demonstrates that cross-species amplification and genotyping using the Illumina Golden Gate Array is a useful method to identify a large number of SNPs in closely related species, although issues with ascertainment bias may limit the type of studies where this method can be applied. 相似文献
930.