PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Craniofacial Abnormalities”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources
PubMed1997

Genetic background effects on dental and other craniofacial abnormalities in homozygous small eye (Pax6Sey/Pax6Sey) mice.

Small eye (Pax6Sey) is a semi-dominant mutation affecting development of the eyes, brain and nasal structures. The mutant phenotype arises from defects within the Pax6 gene and several mutant alleles have been identified. A previous study reported that Pax6Sey/Pax6Sey homozygotes, in a random-bred stock, had a median cartilaginous rod-like structure in the nasal region and 80% had supernumerary upper incisor teeth. In this study we show that supernumerary upper incisor teeth and a previously unreported nasal capsule-derived cartilaginous 'spur' occur in compound heterozygous Pax6Sey-Neu/Pax6Sey and homozygous Pax6Sey/Pax6Sey fetuses from several strains of mice. The frequencies of the abnormal phenotypes were not related to allele type but showed variable penetrance, which was dependent on genetic background. The median nasal cartilaginous rod-like structure was present in all homozygous small eye fetuses. The Pax6Sey/Pax6Sey homozygote may provide insight into the complex gene interactions involved in eye, nasal and craniofacial morphogenesis.

Animals↗
PubMed1990

Prenatal detection and fetal surgery of clefts and craniofacial abnormalities in humans: social and ethical issues.

Sophisticated prenatal diagnostic imaging has facilitated the progression of fetal surgery from the experimental possibility to a clinical therapy for several life-threatening congenital conditions. Guidelines for such fetal surgery include the expectation that the child will be reasonably healthy as a result and that the in utero approach will improve the outcome or is safer than postnatal intervention. Prenatal ultrasound detection of craniofacial anomalies is now common. Reports of experimental cleft repairs in animal fetuses suggest advantages including diminished scarring, improved health and nursing. While fetal craniofacial surgery has not been attempted in humans, speculations exist about the psychological and social benefits of being born with a repaired defect. Fetal surgery is an emerging technology that may alter experimentation, cleft treatment, and the allocation of scarce resources. This paper examines the social and ethical implications of prenatal diagnosis and fetal surgery, focusing on fetal/maternal rights, and clinical decision making.

Animal Experimentation↗
PubMed1989

Craniofacial abnormalities induced by ectopic expression of the homeobox gene Hox-1.1 in transgenic mice.

Hox-1.1 is a murine homeobox-containing gene expressed in a time- and cell-specific manner during embryogenesis. We have generated transgenic mice that ectopically express Hox-1.1 from the chicken beta-actin promoter. In these mice Hox-1.1 expression was changed to an almost ubiquitous pattern. Ectopic expression of Hox-1.1 leads to death of the transgenic animals shortly after birth and is associated with multiple craniofacial anomalies, such as cleft palate, open eyes at birth, and nonfused pinnae. This phenotype is similar to the effects seen after systemic administration of retinoic acid during gestation. This suggests that retinoic acid embryopathy and the specific developmental defects caused by ectopic expression of a potential developmental control gene share a common pathogenic mechanism.

Abnormalities, Multiple↗
PubMedDate not supplied

Abnormal craniofacial morphology and cartilage structure in transgenic mice harboring a Gly --> Cys mutation in the cartilage-specific type II collagen gene.

Gross morphology and histology of the craniofacial complex was studied in the offspring of two transgenic founder mice, Gly85-1 and Gly85-3, carrying several copies of a mouse type II collagen transgene that causes a single amino acid substitution (Gly-->Cys) at position 85 of the triple helix. The newborn transgenic mice had a short snout and mandible, a protruding tongue, a cleft of the secondary palate with the tongue situated between the shelves, and a doming cranial vault. Radiological examination revealed that the cranial base of the transgenic mice was shorter and its posterior part downward bent; in addition both the palate and the cribriform plate were less extended in relation to the cranial base than in the controls. Histologically the midline cartilaginous structures were composed of densely packed enlarged chondrocytes in a reduced extracellular matrix containing abnormally thick collagen fibrils. With the exception of the zone of hypertrophic chondrocytes the matrix also showed a loss of glycosaminoglycans. The cellular architecture of the basicranial synchondroses was disorganized, and the nasocerebrally oriented collagen fibrils formed unevenly distributed aggregates. The craniofacial morphology described here for the Gly85 mice shares features typical for other mouse mutations causing short limbed dwarfism. The observations indicate that defective cartilage production causes disproportionate craniofacial growth. Transgenic mice with specific mutations in cartilage-specific genes should therefore be useful for elucidating the complex mechanisms involved in determining the craniofacial growth.

Animals↗
PubMed1988

The application of molecular genetics to detection of craniofacial abnormality.

Congenital malformations such as secondary cleft palate can be exclusively monogenic or polygenic, but most cases have a multifactorial origin involving both environmental and genetic factors, making genetic analysis difficult. The new techniques of molecular genetics have allowed the successful chromosomal localization of mutant genes in disorders that show a simple Mendelian segregation, whether autosomal dominant (e.g. Huntington's disease), autosomal recessive (cystic fibrosis) or X-linked (Duchenne muscular dystrophy). Recently, a large Icelandic family (over 280 members) with X-linked secondary cleft palate and ankyloglossia (tongue-tied) has been used as a model to localize the mutant gene associated with this craniofacial clefting. The gene has been sub-chromosomally localized to Xq13-q21.1, using anonymous probe DXYS1; a LOD score of 3.07 was obtained. We are preparing cosmid libraries from DNA from mouse cell lines containing only the relevant part of the human X chromosome, introduced by chromosome-mediated gene transfer. Cosmids that contain human X-chromosome sequences will be isolated and analysed for overlapping sequences and RFLPs (restriction fragment length polymorphisms) and the regions further defined by pulsed-field gel electrophoresis and the identification of coding sequences. This should give data on the location and structure of a gene involved in the craniofacial development of the human palatine shelves. This gene, and its protein product, will identify one component of the pathway that causes nonfusion of the palate. In the long term, the understanding of the expression of this sex-linked gene for secondary cleft palate and ankyloglossia will provide a model for the molecular identification of other genes regulating processes in craniofacial development whose expression is hidden in phenotypic, polygenic complexity.

Cleft Palate↗
PubMedDate not supplied

Craniofacial abnormalities in animal models of mucopolysaccharidoses I, VI, and VII.

The genetic mucopolysaccharidoses (MPS) are a family of lysosomal storage diseases resulting from the partial catabolism of several glycosaminoglycans (GAGs). Depending on the particular enzyme deficient in activity, the MPS syndromes are defined into groups MPS I through VII, with several subgroups for a total of 10 disorders. In humans, clinical features include dysostosis multiplex, hepatosplenomegaly, hypertelorism, macroglossia, hypoplastic and irregularly shaped teeth, hyperplastic lips and gingiva, facial dysmorphia, corneal clouding, and mental retardation. MPS I (alpha-L-iduronidase deficiency) and VI (arylsulfatase B deficiency) have been described in cats, MPS VII (beta-glucuronidase deficiency) in dogs. Biochemically, these syndromes appear the same as their human counterparts and have similar clinical characteristics. All are inherited as autosomal recessive traits. The purpose of this study was to analyze the craniofacial aspects of these diseases in the animal models and compare these data with descriptions of the human syndromes. A total of 28 live animals were examined. Thirty-one skulls prepared from postmortem specimens were measured directly and radiographed. Controls were closely related family members of the same sex and similar age without the disease, clinically or biochemically. The data indicated that, as in the human syndromes, each is distinct, and the skull bones most severely affected are those of endochondral origin.

Animals↗
PubMed1985

Craniofacial abnormalities in osteopetrosis with precocious manifestations: report of a case with serial cephalometric roentgenograms.

Serial roentgencephalograms were taken (from the age of 2 to 8 years) of a female patient with malignant osteopetrosis. The roentgencephalograms were compared to those of a control patient with cleft lip and to other normative data. The calvaria of the osteopetrosis patient was very thick, increasing with age. The intracranial space was reduced in volume, resulting in compression of the brain. Roentgencephalometric characteristics of the facial skeleton included orbital hypertelorism, defective horizontal and vertical growth of the middle and lower face, and poorly developed dentoalveolar structures. The mandibular body was short in contrast to the wide ramus, both resulting from defective resorption of the anterior ramal border. A cone-shaped structure in the mandible extending from the condylar process into the ramus was noted. This was believed to consist of remnants of unresorbed, heavily calcified secondary cartilage constituting part of the condylar process present since intrauterine life. Recent treatment of malignant osteopetrosis by bone marrow transplantation early in life has resulted in some cases in normalization of bone structure and marrow. Serial roentgencephalometry provides a sensitive method of assessing craniofacial development in cases of osteopetrosis and presumably can be used to evaluate the effects of therapy.

Cephalometry↗
PubMed1984

Brief clinical report: an X-linked mental retardation syndrome with craniofacial abnormalities, microcephaly and club foot.

A male infant, who died of renal insufficiency at 6 months, had 2 similarly affected maternal uncles who died at 16 and 6 months respectively. Their manifestations include microcephaly, a large anterior fontanel, short nose with anteverted nostrils, club foot deformity, retarded psychomotor development and, in the index case only, kidney hypoplasia and dysplasia. The 2 obligatory carriers of this evidently X-linked recessive syndrome had no physical abnormalities.

Abnormalities, Multiple↗
PubMed1988

Aglossia with congenital absence of the mandibular rami and other craniofacial abnormalities.

We describe a severe first branchial arch abnormality including nearly complete absence of mandible, hypoplasia of the maxilla and the zygomatic arches, and complete gingival fusion in a chromosomally normal child born to a nonconsanguineous couple who deny prenatal exposures. A tight orbicularis oris muscle caused the lips to be constantly pursed. Intraoral contents could only be defined after the fused gingiva were separated. The infant had hypoplasia of the buccal cavity with a persistent membrane separating it from the pharynx; palate structures and tongue were absent. The orbits and midface were severely hypoplastic. However, the ears were normal in shape and only slightly low in position. There was unilateral optic nerve coloboma and coronal craniosynostosis. The only noncraniofacial malformation was an atrial septal defect. Embryologically, there is severe malformation of structures arising from the cephalic neural crest cells of both the maxillary and mandibular prominences of the first branchial arch. However, the first branchial cleft region was spared.

Facial Bones↗
PubMed2000

[Distraction osteogenesis of the mandible in craniofacial abnormalities].

In recent years, lengthening the human mandible by distraction osteogenesis has become an accepted treatment to correct severe mandibular hypoplasia. Using intraoral unidirectional and extraoral bidirectional distraction devices we report about our experiences and results in the application of the bone distraction technique in four selected cases of syndromal disease, including various forms of mandibular hypoplastic malformations. The patients involved were a boy with Pierre Robin syndrome, a girl with unilateral facial hypoplasia in Goldenhar's syndrome, a case with Nager's syndrome, and a rare case of midline deficiency caused by partial deletion of chromosome 18 (18p-syndrome). The distraction period lasted from 6 to 30 days and new bone formation, ranging from 6 to 28 mm, was achieved.

Adolescent↗
PubMed1994

Uchida rat (rSey): a new mutant rat with craniofacial abnormalities resembling those of the mouse Sey mutant.

A new mutant rat with small eyes (rSey) which was found in the course of breeding Sprague-Dawley rats is described. Genetic analysis demonstrates that rSey is inherited as an autosomal dominant mutation. Heterozygotes (rSey/+) have small eyes, while homozygotes (rSey/rSey) do not develop lens and nasal placodes, resulting in lack of eyes and the nose and perinatal death. rSey does not affect any other cranial regions including the maxilla, mandible, hyoid arch and otic vesicles. The genetics and phenotype of the mutant rat closely resemble the Sey mutation in the mouse, suggesting that rSey is the rat counterpart of the Sey mouse. Tissue recombination studies indicate that ectoderm from homozygotes (rSey/rSey) never differentiates into lens tissue even if it is cultured with normal optic vesicles from rSey/+ or +/+ embryos. In contrast, lens differentiation occurs when ectoderm from rSey/+ or +/+ as well as rSey/rSey embryos. These results suggest that the failure of head ectoderm from rSey/rSey embryos to differentiate into lens results from defects in the early differentiation signaling from the neural plate or underlying mesenchyme before the optic vesicle grows out to contact the head ectoderm.

Abnormalities, Multiple↗
PubMed1994

Insertional mutation on mouse chromosome 18 with vestibular and craniofacial abnormalities.

A dominant mutation was generated in transgenic mice as a consequence of insertional mutation. Heterozygous mice from transgenic line 9257 (Tg9257) are hyperactive with bidirectional circling behavior and have a distinctive facial appearance due to hypoplasia of the nasal bone. Morphological analysis of the inner ear revealed asymmetric abnormalities of the horizontal canal and flattening or invagination of the crista ampullaris, which can account for the circling behavior. The sensory epithelium appeared to be normal. The transgene insertion site was localized by in situ hybridization to the B1 band of mouse chromosome 18. Genetic mapping in an interspecific backcross demonstrated the gene order centromere--Tg9257--8.8 +/- 3.4--Grl-1, Egr-1, Fgf-1, Apc--14.7 +/- 4.3--Pdgfr. The phenotype and the mapping data suggest that the transgene may be inserted at the Twirler locus. Homozygosity for the transgene results in prenatal lethality, but compound heterozygotes carrying the Tw allele and the transgene are viable. The function of the closely linked ataxia locus is not disrupted by the transgene insertion. This insertional mutant will provide molecular access to genes located in the Twirler region of mouse chromosome 18.

Amylases↗
PubMed1984

Use of a temporal musculoperiosteal flap in the treatment of craniofacial abnormalities: experimental study.

In 15 juvenile Yorkshire pigs averaging 23.5 kg in weight, 15 periosteal flaps based on the temporal muscle were raised on each side. One side served as control after the temporal arteries were severed. These periosteal flaps were transposed into the infraorbital region and were fixed to the maxillary periosteum by means of a subciliary incision. Radiographic follow-up over 1 year revealed new bone formation. Sample biopsies were microscopically examined and demonstrated the presence of new bone.

Animals↗
PubMed1988

Small eye (Sey): a mouse model for the genetic analysis of craniofacial abnormalities.

Small eye (Sey) is a dominant mutation in the mouse affecting the embryonic development of the eyes and nose. In homozygous Sey/Sey embryos, the optic vesicles grow out but there is no lens induction and the nasal pits fail to develop. Scanning electron microscope studies of Sey/Sey embryos show that the maxillary processes develop normally and fuse with ridges of ectoderm in the frontonasal position. In Sey/+ heterozygotes, the vacuolated lens is smaller than normal, and there is folding of the margins of the optic cup and ingrowth of mesodermal cells. Evidence is presented that Sey is not allelic with Coloboma (Cm), another mutation affecting eye development on chromosome 2.

Animals↗
PubMed1995

The role of sutures in normal and abnormal craniofacial growth.

The paper is a shortened version of a paper read at the symposium on craniofacial growth, in which the literature on various aspects of sutures was reviewed. Suture development, structure, growth, and closure are covered, and the response of sutures to orthopedic forces and their role in craniosynostosis exemplified. Rather than being an extensive review, references are included preferably to present diversity in results and methods within the subtitle of the symposium, 'mechanisms and study methods'.

Animals↗