scholarly journals Gene genealogy in a population of variable size

Heredity ◽  
1997 ◽  
Vol 78 (4) ◽  
pp. 417-423 ◽  
Author(s):  
Bruce Rannala
Keyword(s):  
Variable Size ◽  
Gene Genealogy

scholarly journals DNA methylation epi-signature is associated with two molecularly and phenotypically distinct clinical subtypes of Phelan-McDermid syndrome

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
L. C. Schenkel ◽  
E. Aref-Eshghi ◽  
K. Rooney ◽  
J. Kerkhof ◽  
M. A. Levy ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Critical Region ◽  
Deletion Syndrome ◽  
Genetic Defects ◽  
Chromosome 22 ◽  
Incomplete Penetrance ◽  
Variable Size ◽  
Variable Expressivity ◽  
Genome Wide ◽  
22Q13.3 Deletion Syndrome

Abstract Background Phelan-McDermid syndrome is characterized by a range of neurodevelopmental phenotypes with incomplete penetrance and variable expressivity. It is caused by a variable size and breakpoint microdeletions in the distal long arm of chromosome 22, referred to as 22q13.3 deletion syndrome, including the SHANK3 gene. Genetic defects in a growing number of neurodevelopmental genes have been shown to cause genome-wide disruptions in epigenomic profiles referred to as epi-signatures in affected individuals. Results In this study we assessed genome-wide DNA methylation profiles in a cohort of 22 individuals with Phelan-McDermid syndrome, including 11 individuals with large (2 to 5.8 Mb) 22q13.3 deletions, 10 with small deletions (< 1 Mb) or intragenic variants in SHANK3 and one mosaic case. We describe a novel genome-wide DNA methylation epi-signature in a subset of individuals with Phelan-McDermid syndrome. Conclusion We identified the critical region including the BRD1 gene as responsible for the Phelan-McDermid syndrome epi-signature. Metabolomic profiles of individuals with the DNA methylation epi-signature showed significantly different metabolomic profiles indicating evidence of two molecularly and phenotypically distinct clinical subtypes of Phelan-McDermid syndrome.

scholarly journals Gastrodermis ultrastructure of the different life stages of the polyopisthocotylean monogenean gill parasite Discocotyle sagittata

2021 ◽  
Author(s):  
Joanne Cable ◽  
Mohamed Mohamed El-Naggar
Keyword(s):  
Salmo Trutta ◽  
Structural Organization ◽  
Alimentary Tract ◽  
Blood Feeding ◽  
Life Stages ◽  
Variable Size ◽  
Digestive Cells ◽  
Gill Parasite ◽  
Apical Cytoplasm ◽  
Gill Lamellae

AbstractThe polyopisthocotylean Discocotyle sagittata is a blood-feeding monogenean that infects the gill lamellae of rainbow trout, Oncorhynchus mykiss, and brown trout, Salmo trutta. The ultrastructure of their alimentary tract, at different stages of the life cycle, was previously unknown. Here, we show that the gastrodermis of the oncomiracidium, subadult, and adult D. sagittata follows the same structural organization as that of other blood-feeding polyopisthocotyleans, being composed of digestive cells alternating with a connecting syncytium. Digestive cells of the oncomiracidium are found in three developmental forms: undifferentiated, developing differentiated, and differentiated (presumably functioning) cells whereas those of adult and subadult are present in a single functioning state with variable size and content. The apical cytoplasm of adult digestive cells forms conical outgrowths, a feature which is absent in the oncomiracidium. The connecting syncytium of the oncomiracidium has no evidence of metabolic activity, while that of adult and subadult is metabolically active. The lamellae of the connecting syncytium of adults and subadults are more numerous and larger, and their terminal portions are expanded, compared with those of the oncomiracidium. Parallel, tubular, membranous structures are characteristic of the apical cytoplasm of the connecting syncytium of the oncomiracidium. Luminal lamella in the oncomiracidium, subadult, and adult form balloon-like structures enclosing some luminal contents, but those of the oncomiracidium are larger, bounded by nucleated cytoplasmic layer, and enclose more luminal contents. The possible functions of these structures and mechanism of digestion in both oncomiracidium and adult are discussed.

Comparative gene genealogical analyses of strains of serotype AD identify recombination in populations of serotypes A and D in the human pathogenic yeast Cryptococcus neoformans

Microbiology ◽  
2003 ◽  
Vol 149 (8) ◽  
pp. 2147-2154 ◽  
Author(s):  
Jianping Xu ◽  
Thomas G. Mitchell
Keyword(s):  
Monoclonal Antibodies ◽  
Cryptococcus Neoformans ◽  
Natural Populations ◽  
The Other ◽  
Pathogenic Yeast ◽  
Gene Genealogy ◽  
Serotype A ◽  
The World ◽  
Significant Divergence ◽  
Allelic Group

Cryptococcus neoformans is a major pathogen of humans throughout the world. Using commercial monoclonal antibodies to capsular epitopes, strains of C. neoformans manifest five serotypes: A, B, C, D and AD. Previous studies demonstrated significant divergence among serotypes A, B, C and D, which are typically haploid. In contrast, most strains of serotype AD are diploid or aneuploid and result from recent hybridization between strains of serotypes A and D. Whether serotypes A, B, C and D represent strictly asexual lineages is not known. Using comparative genealogical analyses of two genes, the authors investigated whether recombination occurred among strains within serotypes A and D. For each of 14 serotype AD strains, a portion (642 bp) of the orotidine monophosphate pyrophosphorylase (URA5) gene was cloned and sequenced. Each of these 14 strains contained two different alleles and sequences for both alleles were obtained. The URA5 gene genealogy was compared to that derived from the laccase (LAC) gene, which was reported recently for the same 14 strains. For both genes, each of the 14 serotype AD strains contained two phylogenetically distinct alleles: one allele was highly similar to those from serotype A strains and the other to alleles from serotype D strains. However, within both the serotype A allelic group and the serotype D allelic group, there was significant incongruence between genealogies derived from URA5 and LAC. The results suggest recombination in natural populations of both serotypes A and D.

Possible immunological damage to the tegument ofHymenolepis diminutain mice and rats

Parasitology ◽  
1975 ◽  
Vol 71 (3) ◽  
pp. 525-534 ◽  
Author(s):  
A. D. Befus ◽  
L. T. Threadgold
Keyword(s):  
Lipid Droplets ◽  
Cell Injury ◽  
Mechanical Damage ◽  
Neck Region ◽  
Host Immunity ◽  
Hymenolepis Diminuta ◽  
Intensity Of Infection ◽  
Variable Size ◽  
Abnormal Mitochondria ◽  
Worm Expulsion

Opaque or darkened areas (DA) of variable size and position occur onHymenolepis diminutain mice and rats. In mice DA normally first appear in the neck region of the worm but subsequently they appear elsewhere and increase in number until destrobilation or worm expulsion. The posterior of destrobilated worms is often darkened. In the more immunogenic infections with six cysticercoids there are more DA per worm than in infections with one cysticercoid. DA are areas of the tegument with a homogeneous increase in electron density; abnormal mitochondria; reduced granular endoplasmic reticulum, Golgi complexes and discoidal secretory bodies; and accumulation of lipid droplets. DA disappear from worms maintained for up to 4 h in Hanks' balanced salt solution and can be induced by mechanical damage to the worms.As the numbers of DA increase with the duration and intensity of infection and have similarities with types of cell injury, they are probably sites of worm pathology induced by host immunity.

scholarly journals A variable size mechanism of distributed graph programs and its performance evaluation in agent control problems

2014 ◽  
Vol 41 (4) ◽  
pp. 1663-1671
Author(s):  
Shingo Mabu ◽  
Kotaro Hirasawa ◽  
Masanao Obayashi ◽  
Takashi Kuremoto
Keyword(s):  
Performance Evaluation ◽  
Control Problems ◽  
Variable Size ◽  
Agent Control
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