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At least 253 records · Page 14Linked to original sources
PubMed1998

Differentiation of Allium carlaviruses isolated from different parts of the world based on the viral coat protein sequence.

Common primers which amplify the 3' terminal genomic RNAs of Allium carlaviruses were designed based on the nucleotide sequence of shallot latent virus (SLV), garlic latent virus (GLV) and garlic common latent virus (GCLV). A total of fifteen cDNAs encoding the coat protein (CP) of the carlaviruses, including the biologically identified isolates SLV, GLV and GCLV as well as viruses from infected Allium plants cultivated in different parts of the world, were amplified by RT-PCR with the common primers. The cDNAs were then cloned and sequenced. The predicted viral CP amino acid sequence as well as the nucleotide sequence revealed that SLV and GLV, previously considered as separate viruses on the basis of their biological and physical properties, belong to the same species of the genus Carlavirus. Both viruses are clearly differentiated from GCLV. In addition, every SLV and GLV isolate from the Allium plants in Taiwan showed characteristic and common variations in their CP sequences, suggesting the possible presence of geographical variants. However, no apparent sequence variations of SLV and GLV related to their host plant species, including A. sativum, A. wakegi, A. chinense, A. fistulosum, A. cepa and A. ampeloprasum, were observed. These findings suggested that the sequence variations observed in the respective virus isolates do not correlate with the specificity of their infectivities for Allium species.

Allium↗
PubMed2000

Use of single nucleotide polymorphisms for gene discovery in hypertension.

Genetic susceptibility to common diseases is likely influenced by common DNA variants with small-to-moderate effects, rather than by rare mutations with large effects. The majority of such common variation occurs in the form of single nucleotide polymorphisms (SNPs). DNA sequence variation, including SNPs, is created and maintained by the action of evolutionary forces such as mutation, recombination, and selection. Over time and space, these forces have shaped the relationships between the contemporary organization of the human genome and disease susceptibility in the population at large. Single nucleotide polymorphisms have emerged as valuable new tools to uncover these relationships. In particular, their use in both genome-wide and gene-based association studies holds great promise for the identification of genes and gene variations involved in predisposition to essential hypertension. New advances in biotechnology are making possible large-scale discovery of SNP variation and rapid application of this information to disease gene discovery.

Base Sequence↗
PubMed1982

Principal components of craniofacial growth for white Philadelphia males and females between 6 and 22 years of age.

Three principal components, explaining 83 percent of the common variation for 999 males and females between 6 and 22 years of age, describe ontogenetic patterns of relationship for seven facial dimensions, including sella-nasion, sella-basion, nasion-prosthion, infradentale-menton, articulare-gnathion, gonion-gnathion, and articulare-gonion. Accounting for 65 percent of the variation, a general component associated with both size and shape defines size-required changes in proprotion during growth. Independent patterns of regional variation associated with alveolar remodeling (second component) and condylar growth (third component) describe specific sources of facial modification. Mean multivariate component scores reveal that sexual dimorphism, which progressively favors males over females with age, results from accumulating differences in size and related proportional changes in shape. The timing of the condylar growth spurt, as evident from variation in ramus height, produces secondary dimorphism which diminishes following the adolescent phase in males. Significant age effects are indicated for alveolar remodeling and mandibular growth of the condyle.

Adolescent↗
PubMed1994

Separation of hippocampal theta dipoles by partial coherence analysis in the rat.

In order to separate the effect of different theta generators in the hippocampus and to characterize the pattern of relationships between them, in this study, we calculated the coherence that remains between EEG signals, recorded (1) in the stratum oriens of the CA1 region and (2) close to the hippocampal fissure in the dentate gyrus of the right or left hippocampus, after the variations, common also for a third recording site is eliminated (partialization). We found that in both anesthetized and freely moving rats, there is a selective high correlation (coherence) between theta rhythmic activities of contralateral homonymous sites of the hippocampus. The coherence between field potentials recorded in ipsilateral superficial and deep layers was eliminated when allowance was made for any of the contralateral hippocampal recordings. On the other hand, coherence between contralateral homonymous theta dipoles did not decrease when partialized by a heteronymous hippocampal EEG signal. The present results support earlier findings on multiple hippocampal theta dipoles and indicate that they can be separated using partial coherence analysis. The left and right superficial and deep dipoles oscillate as if they formed two separate systems one extending over the superficial CA1 layers on both sides and the other consisting of the left and right deep hippocampal theta dipoles. The results also suggest an important role of the commissural projections in interhemispheric theta synchronization.

Animals↗
PubMed1988

DNA polymorphisms of the apolipoprotein genes--their use in the investigation of the genetic component of hyperlipidaemia and atherosclerosis.

DNA probes for all eight of the major apolipoprotein genes are now available. The chromosomal location, the basic structure and in many cases the nucleotide sequences of the normal genes are known. Common DNA polymorphisms of all of the genes have been detected. These have been been used in a number of ways to investigate rare inherited defects of the apolipoprotein genes, to study the potential involvement of different variants of the genes in the development of hyperlipidaemia in patients, and to investigate the contribution of common variation in these genes in the determination of serum lipid levels in the normal population.

Apolipoproteins↗
PubMed1993

Ataxia-telangiectasia. Review of the literature and a case report.

Cutaneous vascular abnormalities are frequently detected on initial examination of newborns. Many of these lesions are common variations of normal lesions such as nevus simplex and strawberry hemangiomas. Some of the vascular abnormalities, however, are a feature of a number of syndromes with multisystemic involvement. These syndromes have been described under the heading of neurocutaneous diseases. Ataxia-telangiectasia is a neurocutaneous syndrome that appears with progressive cerebellar ataxia, oculocutaneous telangiectasias, and abnormalities of many other organs. Oral mucosa is also affected. Current concepts on the pathogenesis of ataxia-telangiectasia and one case of the disease are presented in this article.

Adult↗
PubMed1992

Concentrations of particulate and gaseous polycyclic aromatic hydrocarbons in London air following a reduction in the lead content of petrol in the United Kingdom.

The environmental importance of tropospheric polycyclic aromatic hydrocarbons (PAH) is reviewed. The impact of reducing lead on airborne PAH is indicated and the importance of monitoring both particulate and gaseous-phase PAH is demonstrated. A Brief description of a sampling regime performed from 1985 to 1987 is given. Sampling of 18 PAH was performed and particulate lead concentrations at the kerbside were measured concurrently. Measurements indicate that there is a pronounced seasonality in PAH concentrations and in the distribution of PAH between particulate and gaseous phases. On average, 47% of the PAH measured were in the gaseous phase, indicating the importance of measuring the volatile fraction. The dominance of the common variation of each PAH was also investigated using principal components analysis. An uneven spread of data prior to and following the reduction in lead content, hindered a thorough examination of the effect of this change on PAH concentrations. However, they appeared to indicate only a small change in PAH concentration and this was linked to an increase in aromatic content of the petrol, which was much less than expected.

Air Pollutants↗
PubMedDate not supplied

Urinary excretion of aluminium: effects of aging and diurnal variation.

Aluminium (Al) is neurotoxic and a relationship between Alzheimer's disease (AD) and Al in drinking water has been suggested in epidemiological studies. In 5 patients with AD, and healthy subjects of whom 5 were aged, 6 were middle-aged and 6 were young adults, Al excretion into the urine was measured using inductively coupled plasma emission spectro-analysis. In healthy subjects, there appeared to be a relationship between age and daily Al excretion, with the highest level in the aged group, followed by the middle-aged and young adult groups. A significant positive correlation between the amount of urine and the Al excretion in the healthy subjects was also observed. Daily A1 excretion in urine in the group of patients with AD tended to be higher than that of the age matched healthy group, but further studies are needed to account for effects of drugs containing Al compounds. The Al excretion in all the groups showed some variation with the time of day, but no definite diurnal variation common to all the subjects was noted. Because of this, the use of spot urine analysis for studying A1 excretion does not seem to be reliable.

Journal Article↗
PubMed2006

Evaluation of quantification methods for real-time PCR minor groove binding hybridization probe assays.

Real-time PCR data analysis for quantification has been the subject of many studies aimed at the identification of new and improved quantification methods. Several analysis methods have been proposed as superior alternatives to the common variations of the threshold crossing method. Notably, sigmoidal and exponential curve fit methods have been proposed. However, these studies have primarily analyzed real-time PCR with intercalating dyes such as SYBR Green. Clinical real-time PCR assays, in contrast, often employ fluorescent probes whose real-time amplification fluorescence curves differ from those of intercalating dyes. In the current study, we compared four analysis methods related to recent literature: two versions of the threshold crossing method, a second derivative maximum method, and a sigmoidal curve fit method. These methods were applied to a clinically relevant real-time human herpes virus type 6 (HHV6) PCR assay that used a minor groove binding (MGB) Eclipse hybridization probe as well as an Epstein-Barr virus (EBV) PCR assay that used an MGB Pleiades hybridization probe. We found that the crossing threshold method yielded more precise results when analyzing the HHV6 assay, which was characterized by lower signal/noise and less developed amplification curve plateaus. In contrast, the EBV assay, characterized by greater signal/noise and amplification curves with plateau regions similar to those observed with intercalating dyes, gave results with statistically similar precision by all four analysis methods.

Automation↗
PubMed2005

Aromatase gene and osteoporosis: relationship of ten polymorphic loci with bone mineral density.

Aromatase activity appears to be important for bone homeostasis in postmenopausal women. In fact, therapy with aromatase inhibitors is associated with bone loss and fractures. A common biallelic A/G polymorphism in the 3'-untranslated region (UTR) of CYP19-aromatase gene has been associated with differences in gene transcription and the risk of estrogen-responsive tumors. We explored the relationship of such a polymorphism and other 9 polymorphisms situated within or near CYP19 gene with bone mass. The study group comprised 286 postmenopausal women. DNA was isolated from peripheral blood. Biallelic and insertion/deletion polymorphisms were analyzed with exonuclease assays using TaqMan probes. A microsatellite polymorphism in intron 4 was studied by capillary electrophoresis. Bone mineral density (BMD) was determined by DXA. In this cross-sectional study, the postmenopausal decrease in bone mass appeared to be slower in women with AA genotype in the 3'UTR, than in those with AG or GG genotypes. Consequently, there were significant genotype-related differences in BMD. In women after age of 60, hip T-scores were: AA -1.3 +/- 0.1, AG -1.3 +/- 0.2, GG -1.9 +/- 0.1 (P = 0.002). Lumbar spine T-scores were: AA -1.9 +/- 10.2, AG -2.2 +/- 0.1, GG -3.0 +/- 0.2 (P = 0.001). Moreover, GG genotype showed a trend for lower free estrogen levels. This polymorphism was strongly linked to a tetranucleotide repeat in intron 4, as well as to other biallelic polymorphisms situated between 3'UTR and I.2 promoter regions. They all were associated with BMD. However, biallelic polymorphisms in the extreme 5' region of CYP19 and two polymorphisms in neighbor genes were not associated with BMD. In conclusion, common variations of CYP19-aromatase are associated with differences in BMD that seem to be important from an individual as well as from a population perspective.

Aromatase↗
PubMed2006

Tryptase genetics and anaphylaxis.

Tryptases secreted by tissue mast cells and basophils can enter the bloodstream. In human subjects tryptases are encoded by several genes and alleles, including alpha, beta, gamma, and delta. Common variations include complete absence of alpha genes. Until recently, alpha tryptase was considered to be the major tryptase secreted at baseline and in mastocytosis. However, lack of alpha tryptase genes has little effect on circulating tryptase levels, which are now thought mainly to consist of inactive pro-beta tryptase secreted constitutively rather than stored in granules with mature tryptases. Pro-beta tryptase levels thus might reflect total body mast cell content. In contrast, mature beta tryptase can increase transiently in severe systemic anaphylaxis and confirm the diagnosis. However, it might fail to increase in food anaphylaxis or might increase nonspecifically in samples acquired after death. Thus pro- and mature beta tryptase measurements are useful but associated with false-negative and false-positive results, which need to be considered in drawing clinical conclusions in cases of suspected anaphylaxis.

Anaphylaxis↗
PubMed2006

Lack of association of 5 SNPs in the vicinity of the insulin-degrading enzyme (IDE) gene with late-onset Alzheimer's disease.

Insulin-degrading enzyme (IDE) is a strong biological and positional candidate gene for Alzheimer's disease (AD). Previously some studies have examined the role of common variation in the IDE gene with AD risk but the results have been inconsistent. In this study we examined the role of 5 SNPs that define a linkage disequilibrium (LD) block spanning 276kb around IDE. Our sample comprised up to 1012 late-onset AD (LOAD) cases and 771 older white controls. In addition, we also examined the association of these SNPs with quantitative measures of AD progression, namely age-at-onset (AAO), disease duration and Mini-Mental State Examination (MMSE) score. None of the SNPs examined in this fairly large case-control sample revealed significant association with AD risk. These SNPs also showed no significant association with AD quantitative traits.

Aged↗
PubMed2004

Changing places. Do changes in the relative deprivation of areas influence limiting long-term illness and mortality among non-migrant people living in non-deprived households?

Numerous studies have investigated the relative importance of contextual (place) and compositional (person) factors in explaining health and mortality variations. Commonly, these studies control for a range of individual characteristics before testing whether one or more contextual variables have a significant impact on the health or mortality outcome. The findings have been inconsistent, although the growing consensus is, first, that contextual effects are significant but are less important than compositional factors and, second, that contextual effects have a stronger impact in studies of morbidity than in studies of mortality. Here we use longitudinal data to examine a related, but rather different, question. Extracting a select group of people from the ONS Longitudinal Study for England and Wales who had not moved house between 1971 and 1991 and who were living in non-deprived households throughout the 20-year period, we tested whether a change in the relative deprivation of the area in which they were living influenced their health and mortality status. The results demonstrate that changes in the relative deprivation of areas are related to health and mortality outcomes in a consistent way for both outcomes, although the results were more significant for morbidity. These findings suggest that neighbourhood-based public health and regeneration programmes may have demonstrable effects on the health of the residents who live there.

Adult↗
PubMed2006

Wavelet basis selection and feature extraction for shift invariant ultrasound foreign body classification.

This paper proposes a novel technique for automatic ultrasound non-destructive foreign body (FB) detection and classification. A signal registration process is introduced to eliminate shift variations commonly encountered in ultrasound signals. Information theory based methods are then developed for wavelet basis selection and feature extraction to facilitate robust FB classification. Probabilistic neural networks are used for FB classification. Experimental results confirm that the wavelet basis selected by the proposed method improves the FB classification accuracy. It is concluded that low order wavelet bases have better ability to distinguish classes with great similarities than their higher order counterparts, while the reverse is true for more divergent classes.

Algorithms↗
PubMed1999

Association between AGT T235 variant and microalbuminuria in Canadian Oji-Cree with type 2 diabetes mellitus.

OBJECTIVE: To assess the association between the common variation in the gene encoding angiotensinogen, AGT, and the presence of microalbuminuria in Canadian Oji-Cree with type 2 diabetes mellitus. RESEARCH DESIGN AND METHODS: We compared the frequencies of the AGT promoter and M235T polymorphisms among three subgroups of adult Oji-Cree: 50 subjects who had type 2 diabetes with microalbuminuria, 6 subjects who had type 2 diabetes without albuminuria and 302 non-diabetic, normotensive subjects. RESULTS: We found the AGT T235 allele was present at a significantly higher frequency, and that T235/T235 homozygotes were significantly more prevalent, among the subjects who had type 2 diabetes with microalbuminuria than among the subjects in the other two groups. CONCLUSIONS: The findings suggest that the AGT T235 allele is a determinant of the nephropathy susceptibility related to type 2 diabetes in these aboriginal Canadians.

Adolescent↗
PubMed2003

Characterization of polymorphic structure of SREBP-2 gene: role in atherosclerosis.

Sterol regulatory element binding proteins (SREBPs) are membrane-bound transcription factors that control the metabolism of cholesterol and fatty acids in mammalian cells. We postulated that polymorphisms (SNPs) in SREBP-2 gene might influence lipid parameters and the risk of coronary atherosclerosis. PCR-SSCP analysis and direct sequencing of DNA from 64 asymptomatic hypercholesterolemic men revealed seven genetic SREBP-2 SNPs. The genotype distribution of four of these SNPs (1668G>T, 1784G>C, 3474T>C and 3705C>T), and their influence on plasma lipid values and clinical parameters was studied in 655 asymptomatic men previously selected for the presence of at least one cardiovascular risk factor (hypertension, hypercholesterolemia, tobacco consumption). No significant relation was found with lipid parameters but there was a significant association between the 1784G>C polymorphism and intima-media thickness (IMT) measured in 497 subjects. Thus, a common variation in the SREBP-2 gene is related with early-stage carotid atherosclerosis in subjects with a risk of cardiovascular events without detectable change in plasma lipid levels.

Adult↗
PubMed1976

Growth graphs for the clinical assessment of infants of varying gestational age.

Two graphs are presented showing means and 1 and 2 SD for growth in weight, length, and head circumference: (1) a fetal-infant graph with lines of growth from 26 weeks of gestational age until one year of age after ""term'' has been reached: and (2) a similarly constructed graph for children ages one through ten years. The standards of growth were obtained from published data in which the subjects received optimal health care. The graphs allow comparisons of infants of varying gestational age with standards for that age. Normal and abnormal deviations in growth are easily identified. Some examples of common variations in physical growth are described.

Body Height↗