Evolution of the WANCY region in amniote mitochondrial DNA

In most vertebrate mitochondrial genomes, the site for initiation of light-strand replication, OL, is found within a cluster of five transfer RNA (tRNA) genes (tRNA(Trp), tRNA(Ala), tRNA(Asn), tRNA(Cys), and tRNA(Tyr)). This region and part of the adjacent cytochrome c oxydase subunit I (COI) gene were sequenced for two crocodilian, two turtle, and one snake species and for Sphenodon punctatus; part of the adjacent nicotinamide adenine dinucleotide dehydrogenase subunit 2 (ND2) gene was also sequenced for the crocodilian and turtle species. All had the typical vertebrate gene order. The turtles and the snake have a lengthy noncoding sequence between the tRNA(Asn) and tRNA(Cys) genes that we assumed to be homologous to the mammalian OL. The crocodilians and Sphenodon lack such a sequence, a condition they share with birds. Most proposed phylogenies for the amniotes require that OL at this position was lost at least twice during their diversification or was evolved independently more than once. Within the five tRNA genes, frequencies of substitutions are much higher in loops than in stems. Many loops vary dramatically in size among the species; in the most extreme case, the D-arm of the Sphenodon tRNA(Cys) is a "D-arm replacement" loop of seven nucleotides. Frequency of transitions in stems is relatively uniform across tRNAs, but frequency of transversions varies greatly. Mismatches in stems are infrequent, and their relative frequency in a specific tRNA is unrelated to the frequency of substitution in the corresponding gene. Several features of mammalian mitochondrial tRNAs are conserved in WANCY tRNAs throughout amniotes. The inferred initiation codon for COI is GTG in crocodilians, turtles, and the snake, a condition they share with fishes, certain amphibians, and birds. TTG appears to be the initiation codon for COI in Sphenodon; if correct, this would be a novel initiation codon for vertebrate mitochondrial DNA. Phylogenetic analyses of the inferred amino acid sequences of ND2 and COI support the sister-group relationship of birds and crocodilians and suggest that mammals are an early derived lineage within the amniotes.      

Novel clinical in vivo roles for indigo carmine: high-magnification chromoscopic colonoscopy

Since the adenoma-carcinoma sequence was first proposed by Morson in the 1970s, it has become widely accepted that detection and subsequent removal of polypoid adenomas from the colon reduces the incidence of colorectal cancer. These adenomas are relatively easy to detect by conventional colonoscopy; however, large population studies have shown that despite resection of polypoid adenomas, interval colorectal cancers still occurred. Recent advances in technology have given today's endoscopists access to high-resolution and high-magnification scopes, which has facilitated detection of flat and depressed colorectal lesions. Current data suggest that such morphologically distinct lesions may account for up to 30% of all colorectal adenomas. Furthermore, flat and depressed lesions of the large bowel may confer greater malignant potential compared to polypoid adenomas. The majority of flat lesions show only subtle changes by conventional colonoscopy, but the use of stains, such as indigocarmine, in addition to magnification colonoscopy can enhance their detection significantly. In this paper, we discuss the rationale for detecting flat colorectal lesions. We explore the use of high-magnification colonoscopy and chromoendoscopy, with particular reference to the application of indigocarmine, in this patient group. We also discuss the novel therapeutic techniques now available for these lesions.     

Apolipoprotein C3 SstI polymorphism and triglyceride levels in Asian Indians

Background  

A close association between Sst I polymorphism in the 3' untranslated region of the apolipoproteinC3 (APOC3 ) gene and levels of plasma triglycerides (TG) had been reported by different investigators. Hypertriglyceridemia(HTG) is a known risk factor for coronary artery disease (CAD) in the context of Asian Indians. We conducted a study on the relationship between APOC3 SstI polymorphism (S1S1, S1S2 and S2S2 genotypes) and plasma TG levels in a group of 139 male healthy volunteers from Northern India.     

Influence of compressive gear on powerlifting performance: role of blood flow restriction training

This study investigated the effects of powerlifting gear on training volume and performance, defined by the squat, bench press, and deadlift. Eighteen powerlifters (18-26 years) were randomized into either a group that trained and competed using compressive gear (CG) or without the gear (NON). Training volume, volume progression, and powerlifting performance were assessed before and after 10 weeks of training. Training volume increased in the first 4 weeks for both groups. Volume lifted for squat and the totals were greater in the CG. There was an increase in squat (19.05 ± 30.97 lb, p = 0.02), deadlift (19.05 ± 21.17 lb, p = 0.001), and the total score (44.00 ± 60.44 lb, p = 0.005) for both the groups. The improvements in squat (CG = 33.85 vs. NON = 5.74, p = 0.07) and totals (CG = 66.59 vs. NON = 23.67, p = 0.15) were greater in the CG. Both groups showed a significant and similar increase in the Wilks scores (+13.54 points, p = 0.03). There was a trend toward greater volume progression in those wearing CG during the initial stages of training. Both the groups significantly improved performance for the squat, and deadlift, and had higher totals, and Wilks scores, indicating significant strength gains. The greater magnitude of improvements in the squat and totals for the CG lifters suggests an ergogenic potential of training with powerlifting gear.     

A case of spontaneous coronary artery disease regression

Coronary angiographic trials have demonstrated that lowering cholesterol can slow the progression of atherosclerosis, limit the formation of new lesions and enhance atherosclerotic regression together with reducing the incidence of clinical events (Waters D, 1996). Spontaneous regression of coronary atherosclerotic lesions is rare. We report the case of a patient with a severe within-stent restenotic lesion whose coronary disease spontaneously regressed 12 months after initial diagnosis, allowing for medical treatment of symptoms rather than repeated intervention. (Int J Cardiovasc Interventions 1999; 2: 121-123)     

Seq4SNPs: new software for retrieval of multiple, accurately annotated DNA sequences, ready formatted for SNP assay design

Background  

In moderate-throughput SNP genotyping there was a gap in the workflow, between choosing a set of SNPs and submitting their sequences to proprietary assay design software, which was not met by existing software. Retrieval and formatting of sequences flanking each SNP, prior to assay design, becomes rate-limiting for more than about ten SNPs, especially if annotated for repetitive regions and adjacent variations. We routinely process up to 50 SNPs at once.     

Estimation of divergence time between two sibling species of the <Emphasis Type="Italic">Anopheles (Kerteszia) cruzii</Emphasis>complex using a multilocus approach

Background  

Anopheles cruzii is the primary human Plasmodium vector in southern and southeastern Brazil. The distribution of this mosquito follows the coast of the Brazilian Atlantic Forest. Previous studies indicated that An. cruzii is a complex of cryptic species.