Correction: Whole exome sequencing reveals HSPA1L as a genetic risk factor for spontaneous preterm birth.

[This corrects the article DOI: 10.1371/journal.pgen.

Whole exome sequencing reveals HSPA1L as a genetic risk factor for spontaneous preterm birth.

Preterm birth is a leading cause of morbidity and mortality in infants. Genetic and environmental factors play a role in the susceptibility to preterm birth, but despite many investigations, the genetic basis for preterm birth remain largely unknown. Our objective was to identify rare, possibly damaging, nucleotide variants in mothers from families with recurrent spontaneous preterm births (SPTB).

The Danish Twin Registry: linking surveys, national registers, and biological information.

Over the last 60 years, the resources and the research in the Danish Twin Registry (DTR) have periodically been summarized. Here, we give a short overview of the DTR and a more comprehensive description of new developments in the twenty-first century. First, we outline our experience over the last decade of combining questionnaire and survey data with national demographic, social, and health registers in Statistics Denmark.

The effect of hyperthyroidism on Müller's muscle contractility in rats.

The objective of this study was to determine if hyperthyroidism affects the responses of Müller's muscle to alpha-1 adrenoceptor agonists and consequently, if these responses might explain thyroid eyelid retraction. Sprague-Dawley adult rats (n = 37) were divided into control and treated groups and given either placebo or intraperitoneal triiodothyronine (250 micrograms/kg/d) for 1, 2, or 3 weeks. A suture was passed through their upper eyelid and connected to a force transducer that measured Müller's muscle contractions.

Solitary fibrous tumor of the orbit.

Purpose: We studied a case of solitary fibrous tumor of the orbit in a 75-year-old man.

Methods: The patient had painless, slowly progressive proptosis of eight months' duration. He underwent magnetic resonance imaging, which showed a well-circumscribed retrobulbar mass.

Acquired blepharoptosis secondary to essential blepharospasm.

We treated four patients with essential blepharospasm, receiving botulinum A toxin, in whom, although they had no preexisting blepharoptosis, a concurrent bilateral acquired blepharoptosis developed. Since the blepharoptosis did not improve after the period of time during which the effects of botulinum A toxin would have been expected to resolve (2 to 10 weeks), we judged that its development was unrelated to the toxin. We propose, rather, that the stretching, attenuation, disinsertion, or dehiscence of the upper eyelid levator muscle caused by the blepharospasm were at least partly responsible for the onset of the blepharoptosis.

Intraocular dexamethasone penetration via subconjunctival or retrobulbar injections in rabbits.

Using high-performance liquid chromatography, we compared tissue levels of dexamethasone in the aqueous, vitreous, retina, and choroid of rabbits, 1 and 4 hours following subconjunctival or retrobulbar injection. One hour following injection, dexamethasone levels in all of these tissues were similar in both the subconjunctival and retrobulbar groups. Four hours following injection, the concentrations in the two groups also were similar, except in the choroid, in which the subconjunctival injection yielded significantly lower dexamethasone levels than the retrobulbar injection.

Postoperative mydriasis after repair of orbital floor fracture.

Mydriasis after operative repair of orbital floor fracture has been attributed to manipulation of the inferior oblique muscle. We treated two patients with mydriasis, one with an isolated mydriatic pupil and the other with a tonic pupil, which followed posterior orbital floor injuries and repair. The posterior location of the fractures suggests that surgical manipulation of or near the ciliary ganglion may account for these phenomena.

Microphthalmos in the presumed homozygous offspring of a first cousin marriage and linkage analysis of a locus in a family with autosomal dominant cerulean congenital cataracts.

A family with autosomal dominant congenital cataracts was studied to determine clinical variability. A total of 159 relatives was ascertained; 17 affected and 19 normal individuals were evaluated and their blood sampled for inclusion in the linkage analysis. The disease was compatible with normal to mildly decreased visual acuity until adult life in all affected except the product of a consanguineous marriage of affected first cousins who was born with bilateral microphthalmos and dense congenital cataracts, attributed to homozygosity of the cataract gene.