The molecular basis for Duchenne versus Becker muscular dystrophy: Correlation of severity with type of deletion

About 60% of both Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) is due to deletions of the dystrophin gene. For cases with a deletion mutation, the "reading frame" hypothesis predicts that BMD patients produce a semifunctional, internally deleted dystrophin protein, whereas DMD patients produce a severely truncated protein that would be unstable. To test the validity of this theory, we analyzed 258 independent deletions at the DMD/BMD locus. The correlation between phenotype and type of deletion mutation is in agreement with the "reading frame" theory in 92% of cases and is of diagnostic and prognostic significance. The distribution and frequency of deletions spanning the entire locus suggests that many "in-frame" deletions of the dystrophin gene are not detected because the individuals bearing them are either asymptomatic or exhibit non-DMD/non-BMD clinical features.     

On potentials and relevance of the use of copulatory structures in anostracan taxonomy

This paper reviews and extends the knowledge of anostracan penile morphology and its taxonomic significance. Since Linder‘s pioneering classification(based partly on male genital characters), the morphology of both basal and distal penile parts has been applied repeatedly to reorganize or establish higher anostracan taxa, or to extend their diagnoses. In general, the configuration of both basal and distal penile structures follows a constant pattern in well-defined genera. Size and shape of processes and spinulation on the basal (in Linderiella and Chirocephalidae) and the distal parts (in Parartemia), however, may show inter-specific differences. Variability in penile structures in the current genus Brachinella indicates the need for a taxonomic revision of this genus. Similar intra-generic penis morphology may contribute to hybridizability of congeners and validate Dubois‘genus concept for use in anostracans. This revised version was published online in August 2006 with corrections to the Cover Date.     

The effect of ACTH on the blood clearance rate of aldosterone, cortisol, 17 alpha-hydroxyprogesterone and 17 alpha, 20 alpha-dihydroxy-4-pregnen-3-one in the sheep

The blood clearance rate (BCR) of aldosterone, cortisol, 17 alpha-hydroxyprogesterone (17 alpha OHP) and 17 alpha, 20 alpha-dihydroxy-4-pregnen-3-one (17 alpha 20 alpha OHP) has been measured in conscious sheep prior to and after 5 or 6 days ACTH treatment. ACTH increased the BCR of cortisol but did not change the BCR of the other three steroids. 17 alpha OHP had a BCR greater than liver blood flow suggesting extra-hepatic metabolism. In vivo conversion of 17 alpha OHP to 17 alpha 20 alpha OHP by ovine red cells has been shown to be a significant site of this metabolism. It is suggested that this conversion of 17 alpha OHP to 17 alpha 20 alpha OHP may be important in the expression of the "hypertensionogenic" effect of 17 alpha OHP.     

A new phylogenetic test for comparing multiple high‐dimensional evolutionary rates suggests interplay of evolutionary rates and modularity in lanternfishes (Myctophiformes; Myctophidae)

The interplay between evolutionary rates and modularity influences the evolution of organismal body plans by both promoting and constraining the magnitude and direction of trait response to ecological conditions. However, few studies have examined whether the best‐fit hypothesis of modularity is the same as the shape subset with the greatest difference in evolutionary rate. Here, we develop a new phylogenetic comparative method for comparing evolutionary rates among high‐dimensional traits, and apply this method to analyze body shape evolution in bioluminescent lanternfishes. We frame the study of evolutionary rates and modularity through analysis of three hypotheses derived from the literature on fish development, biomechanics, and bioluminescent communication. We show that a development‐informed partitioning of shape exhibits the greatest evolutionary rate differences among modules, but that a hydrodynamically informed partitioning is the best‐fit modularity hypothesis. Furthermore, we show that bioluminescent lateral photophores evolve at a similar rate as, and are strongly integrated with, body shape in lanternfishes. These results suggest that overlapping life‐history constraints on development and movement define axes of body shape evolution in lanternfishes, and that the positions of their lateral photophore complexes are likely a passive outcome of the interaction of these ecological pressures.     

A high‐quality genome of taro (Colocasia esculenta (L.) Schott), one of the world's oldest crops

Taro (Colocasia esculenta (L.), Schott), from the Araceae family, is one of the oldest crops with important edible, medicinal, nutritional and economic value. Taro is a highly polymorphic species including diverse genotypes adapted to a broad range of environments, but the taro genome has rarely been investigated. Here, a high‐quality chromosome‐level genome of C. esculenta was assembled using data sequenced by Illumina, PacBio and Nanopore platforms. The assembled genome size was 2,405 Mb with a contig N50 of 400.0 kb and a scaffold N50 of 159.4 Mb. In total, 2,311 Mb (96.09%) of the contig sequences was anchored onto 14 chromosomes to form pseudomolecules, and 2,126 Mb (88.43%) was annotated as repetitive sequences. Of the 28,695 predicted protein‐coding genes, 26,215 genes (91.4%) could be functionally annotated. On the basis of phylogenetic analysis using 769 genes, C. esculenta and Spirodela polyrhiza were placed on one branch of the tree that diverged approximately 73.23 million years ago. The synteny analyses showed that there have been two whole‐genome duplication events in C. esculenta separated by a relatively short gap. According to comparative genome analysis, a larger number (1,189) of distinct gene families and long terminal repeats were enriched in C. esculenta. Our high‐quality taro genome will provide valuable resources for further genetic, ecological and evolutionary analyses of taro or other species in the Araceae.     

Congenital coronary artery-left heart fistulas: Report of three cases

Of 59 patients who underwent operative correction of congenital coronary artery fistulas from May 1956 through May 1980 at our institution, three had fistulas that arose from the coronary artery and terminated in the left heart. The chief indication for surgical correction in such patients is the presence of symptoms or the development of complications, which include rupture, endocarditis, and congestive heart failure. The principal objective of repair is closure or obliteration of the fistulous communication and preservation of distal myocardial perfusion. Because symptoms and complications tend to occur with age, elective ligation is warranted during childhood, even in asymptomatic patients. The three cases described here, as well as the reviewed series of left heart fistulas, substantiate this fact. All three patients were symptomatic before operation and asymptomatic afterward.     

Insulin and the regulation of adipose-tissue acetyl-coenzyme A carboxylase

Rat epididymal fat-pads were incubated for 30min with glucose (2mg/ml) in the presence or absence of insulin. A twofold or greater increase in acetyl-CoA carboxylase activity was observed in extracts from insulin-treated tissue provided that assays were performed rapidly after extraction. This effect of insulin was evident whether or not extracts were prepared with albumin, and was not noticeably diminished by the presence of citrate or albumin or both in the assay. Incubation of extracts before assay led to activation of acetyl-CoA carboxylase and a marked diminution in the insulin effect. The enzyme in extracts was very sensitive to reversible inhibition by palmitoyl-CoA even in the presence of albumin (10mg/ml); inhibition persisted on dilution of enzyme and inhibitor. It is suggested that the observed activation of acetyl-CoA carboxylase by insulin may reflect changes in enzyme activity in the fat-cell resulting from the reduction of long-chain fatty-acyl-CoA that occurs in the presence of insulin. Activation of the enzyme with loss of the insulin effect on incubation of the extracts may be due to the slow dissociation of long-chain fatty acyl-CoA from the enzyme.     

Variation in nicotine consumption in inbred mice is not linked to orosensory ability

Genetic studies of nicotine addiction in mice have utilizedthe oral self-administration model. However, it is unclear ifstrain differences in nicotine consumption are influenced byvariation in bitter taste sensitivity. We measured both nicotineconsumption and nicotine brief-access licking behavior in severalcommonly used inbred strains of mice that were previously shownto differ in nicotine consumption. A/J (A), C57BL/6J (B6), andDBA/2J (D2) mice were given a 2-bottle choice test with a singleconcentration of nicotine (75 µg/ml; nicotine vs. water).Mice of these strains were also tested with a range of nicotineconcentrations (5–400 µg/ml) using a brief-accesstest, which measures orosensory response and minimizes postingestiveeffects. Although B6 mice consumed more 75-µg/ml nicotinethan A or D2 mice in the 2-bottle test, these strains did notdiffer in level of aversion to nicotine when tested with thebrief-access procedure. Strain differences in orosensory responseto nicotine were not found; yet, differences emerged duringthe 2-bottle tests. This study provides evidence that variationin intake level of nicotine is likely not due to differencesin taste or trigeminal sensitivity but likely due to postingestivefactors.