Mechanical memory stored through epigenetic remodeling reduces cell therapeutic potential.

Understanding how cells remember previous mechanical environments to influence their fate, or mechanical memory, informs the design of biomaterials and therapies in medicine. Current regeneration therapies, such as cartilage regeneration procedures, require 2D cell expansion processes to achieve large cell populations critical for the repair of damaged tissues. However, the limit of mechanical priming for cartilage regeneration procedures before inducing long-term mechanical memory following expansion processes is unknown, and mechanisms defining how physical environments influence the therapeutic potential of cells remain poorly understood.

Selection on early survival does not explain germination rate clines in Mimulus cardinalis.

Premise: Many traits covary with environmental gradients to form phenotypic clines. While local adaptation to the environment can generate phenotypic clines, other nonadaptive processes may also. If local adaptation causes phenotypic clines, then the direction of genotypic selection on traits should shift from one end of the cline to the other.

Dynamic biophysical responses of neuronal cell nuclei and cytoskeletal structure following high impulse loading.

Cells are continuously exposed to dynamic environmental cues that influence their behavior. Mechanical cues can influence cellular and genomic architecture, gene expression, and intranuclear mechanics, providing evidence of mechanosensing by the nucleus, and a mechanoreciprocity between the nucleus and environment. Force disruption at the tissue level through aging, disease, or trauma, propagates to the nucleus and can have lasting consequences on proper functioning of the cell and nucleus.

Dispersal evolution in temporally variable environments: implications for plant range dynamics.

Dispersal-the movement of an individual from the site of birth to a different site for reproduction-is an ecological and evolutionary driver of species ranges that shapes patterns of colonization, connectivity, gene flow, and adaptation. In plants, the traits that influence dispersal often vary within and among species, are heritable, and evolve in response to the fitness consequences of moving through heterogeneous landscapes. Spatial and temporal variation in the quality and quantity of habitat are important sources of selection on dispersal strategies across species ranges.

Asymmetric competition impacts evolutionary rescue in a changing environment.

Interspecific competition can strongly influence the evolutionary response of a species to a changing environment, impacting the chance that the species survives or goes extinct. Previous work has shown that when two species compete for a temporally shifting resource distribution, the species lagging behind the resource peak is the first to go extinct due to competitive exclusion. However, this work assumed symmetrically distributed resources and competition.

Missense mutations in β-1,3-N-acetylglucosaminyltransferase 1 (B3GNT1) cause Walker-Warburg syndrome.

Several known or putative glycosyltransferases are required for the synthesis of laminin-binding glycans on alpha-dystroglycan (αDG), including POMT1, POMT2, POMGnT1, LARGE, Fukutin, FKRP, ISPD and GTDC2. Mutations in these glycosyltransferase genes result in defective αDG glycosylation and reduced ligand binding by αDG causing a clinically heterogeneous group of congenital muscular dystrophies, commonly referred to as dystroglycanopathies. The most severe clinical form, Walker-Warburg syndrome (WWS), is characterized by congenital muscular dystrophy and severe neurological and ophthalmological defects.

Mutations in ISPD cause Walker-Warburg syndrome and defective glycosylation of α-dystroglycan.

Walker-Warburg syndrome (WWS) is an autosomal recessive multisystem disorder characterized by complex eye and brain abnormalities with congenital muscular dystrophy (CMD) and aberrant a-dystroglycan glycosylation. Here we report mutations in the ISPD gene (encoding isoprenoid synthase domain containing) as the second most common cause of WWS. Bacterial IspD is a nucleotidyl transferase belonging to a large glycosyltransferase family, but the role of the orthologous protein in chordates is obscure to date, as this phylum does not have the corresponding non-mevalonate isoprenoid biosynthesis pathway.

Familial neurohypophyseal diabetes insipidus due to a novel mutation in the arginine vasopressin-neurophysin II gene.

Background: Familial neurohypophyseal (central) diabetes insipidus (DI) is caused by mutations in the arginine vasopressin-neurophysin II (AVP-NPII) gene. The majority of cases is inherited in an autosomal dominant way. In this study, we present the clinical features of a mother and her son with autosomal dominant neurohypophyseal DI caused by a novel mutation.

A homozygous FKRP start codon mutation is associated with Walker-Warburg syndrome, the severe end of the clinical spectrum.

Dystroglycanopathies are a heterogeneous group of disorders caused by defects in the glycosylation pathway of alpha-dystroglycan. The clinical spectrum ranges from severe congenital muscular dystrophy with structural brain and eye involvement to a relatively mild adult onset limb-girdle muscular dystrophy without brain abnormalities and normal intelligence. Mutations have been identified in one of six putative or demonstrated glycosyltransferases.

Deficiency of Dol-P-Man synthase subunit DPM3 bridges the congenital disorders of glycosylation with the dystroglycanopathies.

Alpha-dystroglycanopathies such as Walker Warburg syndrome represent an important subgroup of the muscular dystrophies that have been related to defective O-mannosylation of alpha-dystroglycan. In many patients, the underlying genetic etiology remains unsolved. Isolated muscular dystrophy has not been described in the congenital disorders of glycosylation (CDG) caused by N-linked protein glycosylation defects.

Constitutional DNA copy number changes in ICSI children.

Background: Over the last three decades, technological developments facilitating assisted reproductive techniques (ART) have revolutionized the treatment of subfertile couples, including men suffering from severe oligospermia or azoospermia. In parallel with the advent of these technologies, there is a great concern about the biological safety of ART. This concern is supported by the clinical observation that the frequency of congenital malformations is slightly elevated among ART-conceived children.

The mitochondrial 13513G > A mutation is most frequent in Leigh syndrome combined with reduced complex I activity, optic atrophy and/or Wolff-Parkinson-White.

The m.13513G > A transition in the mitochondrial gene encoding the ND5 subunit of respiratory chain complex I, can cause mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) and has been reported to be a frequent cause of Leigh syndrome (LS). We determined the frequency of the mutation in a cohort of 123 patients with reduced complex I activity in muscle (n = 113) or fibroblast (n = 10) tissue.

A case of neuromuscular mimicry.

Recognizing an ALS-mimic can be challenging. Here, we describe a patient with a slowly progressive dysarthria and dysphagia, with fasciculations of the tongue and general hyperreflexia, fulfilling the diagnostic criteria of 'clinical probable ALS'. Because of a non-conclusive EMG, a muscle biopsy was performed that surprisingly showed widespread nemaline rods.

The expanding phenotype of POMT1 mutations: from Walker-Warburg syndrome to congenital muscular dystrophy, microcephaly, and mental retardation.

The importance of O-glycosylation of alpha-dystroglycan (alpha-DG) is evident from the identification of POMT1 mutations in Walker-Warburg syndrome (WWS). Approximately one-fifth of the WWS patients show mutations in POMT1, which result in complete loss of protein mannosyltransferase activity. WWS patients are characterized by congenital muscular dystrophy (CMD) with severe brain and eye abnormalities.

POMT2 mutations cause alpha-dystroglycan hypoglycosylation and Walker-Warburg syndrome.

Background: Walker-Warburg syndrome (WWS) is an autosomal recessive condition characterised by congenital muscular dystrophy, structural brain defects, and eye malformations. Typical brain abnormalities are hydrocephalus, lissencephaly, agenesis of the corpus callosum, fusion of the hemispheres, cerebellar hypoplasia, and neuronal overmigration, which causes a cobblestone cortex. Ocular abnormalities include cataract, microphthalmia, buphthalmos, and Peters anomaly.

Estimation of the number of infectious measles viruses in live virus vaccines using quantitative real-time PCR.

The potency of live attenuated virus vaccines is determined by counting or titrating viable viruses in cell cultures. These classical potency tests have the drawback that they are time consuming and laborious and show a high laboratory-to-laboratory variation. In the present study we describe the development and validation of a fast method to measure the potency of measles in trivalent measles, mumps and rubella (MMR) vaccines using quantitative real-time PCR (qPCR).

Homozygous acute intermittent porphyria in a 7-year-old boy with massive excretions of porphyrins and porphyrin precursors.

A 7-year-old boy demonstrating hepatosplenomegaly, mild anaemia, mild mental retardation, yellow-brown teeth and dark red urine had excessively elevated levels of urinary delta-aminolevulinic acid, porphobilinogen and uroporphyrin. Furthermore hepta-, hexa-, penta- and copro(I)porphyrins were highly increased in urine. This pattern of porphyrin precursor and metabolite excretion is characteristic of acute intermittent porphyria.