Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Polydactyly”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 1,117 records · Page 62Linked to original sources
PubMed1995

Tracheal stenting improves airway mechanics in infants with tracheobronchomalacia.

The compliance and expiratory resistance of the tracheobronchial tree is increased in infants with tracheobronchomalacia because of a weakness in cartilaginous support of the airway. Life threatening episodes may occur in these patients due to airway collapse. The goals of this study were to compare the effects on respiratory system mechanics of stenting the airway with either continuous positive airway pressure (CPAP) or a long tracheostomy tube. Five infants were studied: two had bronchopulmonary dysplasia (BPD), 2 had associated congenital anomalies, and one had tracheomalacia and polydactyly; none had a tracheoesophageal fistula. All patients required tracheostomy and were treated with CPAP. Lung mechanics were evaluated by measuring transpulmonary pressure, obtained by subtracting airway opening pressure from pleural pressure measured with an esophageal balloon, and flow measured with a pneumotachometer placed in series with the tracheostomy. Dynamic compliance (Cdyn) and total respiratory system resistance (Rt) were calculated by two-factor, least-mean-squares analysis, solving for the equation of motion of the lung with the PeDS system (MAS, Hatfield). In all subjects Cdyn increased and Rt decreased with increasing CPAP. In 4 subjects the airway was stented with a specially designed, long tracheostomy tube which reached to just above the carina; the special tube improved dynamic mechanics sufficiently to permit the discontinuation of CPAP. Speech was improved by fenestrating the tube and the use of a one-way inspiratory valve, placed over the tracheostomy. Inspiration occurred via the tracheostomy and expiration was directed to the larynx.

Airway Resistance↗
PubMed1997

Changes in registered congenital anomalies in the Republic of Belarus after the Chernobyl accident.

A descriptive analysis of birth defects and malformations was performed to assess whether the rates of these defects correlate with the geographic areas of Belarus that received different levels of 137Cs contamination resulting from the Chernobyl catastrophe. Since this accident in 1986, the frequency of both congenital and fetal abnormalities in the Republic of Belarus has apparently increased. This increase is most prominent in areas with at least 555 9Bq/m2 radioactive contamination, although it has not been possible to correlate the individual dose received by a pregnant woman with the incidence of congenital malformations. The types of anomalies that were most increased in frequency were multiple congenital malformations, polydactyly, and reduction limb defects. These malformations are commonly associated with dominant new mutations. Chromosomal disorders such as occur in Down syndrome were not increased in frequency, nor could teratogenic effects be attributed to exposure to ionizing radiation. Preventive measures have apparently reduced the number of births with congenital abnormalities but have had no apparent effect on the frequency of fetal defects. Results of our analysis are consistent with the hypothesis that ionizing radiation released during the Chernobyl accident may have placed fetuses and neonates at risk for congenital malformations. Epidemiological studies are now required to determine whether a mother's radiation dose correlates with congenital malformations in her children.

Abnormalities, Radiation-Induced↗
PubMed1985

Teratogenic effects of carcinogenic agents on limb regeneration in the Japanese newt Cynops pyrrhogaster.

Normal regeneration of the amputated forelimb of the Japanese newt Cynops pyrrhogaster and regeneration after a single intraperitoneal injection of three potent mutagenic/carcinogenic agents was investigated. Three dose levels of each agent and controls were tested for teratogenicity in this newt model with the following chemicals: N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), 4-nitro-quinoline-1-oxide, and 2-(2-furyl)-3-(5-nitrofuryl)acrylamide. These chemicals were administered at 10 days (late dedifferentiation stage), 20 days (late bud stage), and 30 days (early digits stage) after amputation at the midforelimb. A total of 628 newts, with 16-20 animals per group, were used. Normal forelimb regeneration in Cynops pyrrhogaster closely paralleled that reported for other species. A variety of deformities, including syndactyly, polydactyly, oligodactyly, brachydactyly, and digital branching, were occasionally observed in control regenerating forelimbs, with syndactyly occurring at highest incidence (17.5%). All three mutagens at all tested dose levels enhanced the incidence of teratogenic changes, though increases were not always statistically significant. MNNG, particularly when administered at the time of initial chondrogenesis (20 days, late bud stage), was especially teratogenic. The type of forelimb deformity was not mutagen-specific in this experiment. As Cynops pyrrhogaster is easily and inexpensively maintained and tolerates surgery well, this model with the regenerating forelimb should prove useful for further studies on teratogen screening. Also, studies directed toward mutagenic and epigenetic effects of exogenous agents on rapidly proliferating and differentiating tissues can be investigated with this model, which obviates transplacental excursion and metabolism of test compounds.

4-Nitroquinoline-1-oxide↗
PubMed2001

Do infants with major congenital anomalies have an excess of macrosomia?

BACKGROUND: Infants that develop congenital anomalies may also have an excess prevalence of macrosomia (birth weight > or =4,000 g). This may indicate that abnormalities of glycemic control play a role in the etiology of birth defects. This study was undertaken to determine whether all infants with congenital anomalies have an excess of macrosomia and whether it is confined to specific types of anomalies. METHODS: A case-control study was conducted, comparing the birth weights of 8,226 infants with congenital anomalies ascertained by the Texas Birth Defects Monitoring Division with those of 965,965 infants without birth defects. Odds ratios were calculated to determine the association between birth weight and congenital anomalies, for 45 specific defects, and for all these defects combined. RESULTS: For all 45 defects combined, a significant association occurred only in the highest birth weight category. Infants with congenital anomalies were more likely than infants without birth defects to have a birth weight > or =4,500 g (OR = 1.65; 95% CI = 1.39-1.96). Infants born with ventricular septal defects, atrial septal defects, ventricular hypertrophy, or anomalies of the great vessels were 1.5-2.5 times more likely to weigh > or =4,000 g than were infants without birth defects. Based on small numbers, a stronger excess of macrosomia was observed for infants with encephalocele, holoprosencephaly, anomalies of the corpus callosum, preaxial polydactyly, and omphalocele. CONCLUSIONS: Our data suggest that infants with specific congenital anomalies are more likely to be macrosomic than are infants without an anomaly. If these findings are confirmed, associations between macrosomia and specific types of birth defects may help to identify birth defects that are caused by alterations in glycemic control.

Abnormalities, Multiple↗
PubMed1975

The effects of 5-fluorouracil and 5-fluorodeoxyuridine used alone and in combination with normal nucleic acid precursors on development of mice in lines selected for low and high expression of Strong's luxoid gene.

Pregnant female mice selected for plus- and minus-modifying genes of the limb-skeleton effects of Strong's luxoid gene (1st) were injected ip on day 10 of gestation with 10 or 20 mg/kg 5-fluorouracil (5-FU) or 5-fluorodeoxyuridine (5-FUdR). The incidence and degree of expression of the effects (polydactyly, ectrodactyly, radial hemimelia, tibial hemimelia, pelvic girdle shifts, deformed caudal vertebrae) varied according to the teratogen and dose level. The addition of an equimolecular amount of thymidine, thymine, or uracil greatly potentiated the effects of 20 mg/kg 5-FU, usually resulting in death of the embryos. The addition of an equimolecular amount of thymidine but not of the embryos. The addition of an equimolecular amount of thymidine but not of thymine or uracil partly protected against the effects of 5-FUdR. Both teratogens increased the expression of ist on the limb skeleton. The interactions of the teratogens with the major gene were inhibited by minus- and promoted by plus-modifying genes of 1st. The effects of the teratogenic treatments may be mediated by cell death.

Abnormalities, Drug-Induced↗
PubMed1977

A lethal neonatal dwarfing condition with short ribs, polysyndactyly, cranial synostosis, cleft palate cardiovascular and urogenital anomalies and severe ossification defect.

A case of severe lethal neonatal dwarfism is reported. It appears to be a new variety of short rib-polydactyly dwarfism. It is characterized by severe lack of ossification of all bones except the clavicle and the presence of cleft palate, as well as genitourinary, central nervous system and cardiovascular anomalies. Electronmicroscopy revealed accumulations of granular material in the chondrocytes.

Abnormalities, Multiple↗
PubMed1981

Limb development in mouse embryos. III. Cellular events underlying the determination of altered skeletal patterns following treatment with 5'fluoro-2-deoxyuridine.

A potent inhibitor of thymidylate synthetase, 5-Fluorodeoxyuridine (FUdR), produced dose- and stage-dependent skeletal defects in embryos of mice injected during early development (10th--13th day). The dose of 25 mg/kg was teratogenic producing few resorptions and little reduction in fetal weight. Hindlimbs were much more sensitive to the drug than were the forelimbs and showed dose-dependent long bone reductions. Specific long bone reductions occurred after treatment on the 11th or 11.5 day and were accompanied by preaxial polydactyly; treatment on the 12th or 12.5 day produced high incidence of ectrodactyly but no long bone reductions. Limbs were insensitive on the 13th day of development and beyond. Limb buds in organ culture demonstrated a direct action of FUdR on undifferentiated mesenchymal cells, incurring what has been previously termed "thymineless" cell death. Dose-dependent reduction of viable cell number led to a reduction in chondrogenic expression in vitro--more so in the hindlimb than the forelimb. Similar occurrence of cell death was also noted after in utero exposure, and here, it was followed by a process of recovery. The recovery phase was characterized by the formation of a distal synchronized cell population derived from undamaged subridge cells leaving damaged cells at the proximal extent of the subridge zone. Limb segments maintained their temporal sequence of differentiation, and their regulatory capability was related to the time allotted for repopulation of the subridge zone. We propose that a faster growth during early development of the elements of the hindlimb versus analogous ones of the forelimb allows the former less time for regulation--and hence, higher sensitivity to antiproliferative agents such as FUdR.

Animals↗
PubMed1982

Interactions between cycloheximide and T-locus alleles during mouse embryogenesis.

Female CD-1 mice were mated with CD-1 X T/ + F1 males that were heterozygous for the brachyury (T') semidominant lethal gene or were +/+. Fetuses from CD-1 X +/+ matings were normal when observed on gestation Day 17 (plug day = Day 0). Those from the CD-1 X T/+ cross exhibited the expected 1:1 ratio of short:normal tail lengths, but 10% of these fetuses were tailless, apparently due to factors in the CD-1 genotype that increased the expressivity of the T-gene with regard to reduction of tail length. Additional CD-1 females were mated with CD-1 X tw18/+ F1 males. Fetuses from the CD-1 X tw18/+ matings were normal. CD-1 females carrying CD-1 X +/+, CD-1 X T/+, or CD-1 X tw18/+ litters were injected ip on gestation Day 9 with 30 mg/kg cycloheximide or were untreated. Cycloheximide was teratogenic for litters from all three crosses. Polydactyly, oligodactyly, and a variety of skeletal abnormalities were observed. Gross malformations and total skeletal malformations were increased in treated CD-1 X T/ + or tw18/+ litters in comparison with CD-1 X +/+ litters, as were nonvertebral skeletal defects in CD-1 X tw18/+ litters. Prenatal mortality was also greater in treated mutant-containing litters than in +/+ litters, and fetal weights were similarly decreased in treated CD-1 X tw18/+ litters. The incidence of taillessness was also higher in treated (26%) than in control (10%) CD-1 X T/+ litters. Thus both the T and tw18 alleles appear to have enhanced the teratogenicity of cycloheximide, and the inhibitor may have increased the expressivity of T.

Abnormalities, Drug-Induced↗
PubMed1985

Visceral anomalies in the Meckel syndrome.

The visceral abnormalities of 32 autopsied Meckel's syndrome cases were analysed macroscopically and histologically in order to observe the distribution and spectrum of internal abnormalities in this hereditary malformation syndrome. All cases showed the classical triad of central nervous system anomaly, postaxial polydactyly, and cystic kidneys. Five cases were midterm fetuses and 27 cases were perinatal deaths. The kidneys were grossly enlarged in almost all of the cases (29) and showed a uniform histological pattern of fibrocystic proliferation, which is considered characteristic of MS. Fibrosis and proliferation of the bile ducts in the hepatic portal tracts were found in each case. Severe hypoplasia of the male genitalia associated with cryptorchidism was the third consistent anomaly. Derivatives of the müllerian ducts were present in four males, and the initial sex determination of the male infants was sometimes difficult. Epididymal cysts (39%) and ductal dilatation as well as fibrosis of the pancreas (31%) were further common anomalies. This series showed that a number of gross and microscopic abnormalities are consistently present in MS and that histological investigation is invaluable in defining the syndrome in doubtful cases.

Abnormalities, Multiple↗
PubMed1985

Teratogenicity of dimethoxyethyl phthalate and its metabolites methoxyethanol and methoxyacetic acid in the rat.

It is hypothesized that the known teratogen di(2-methoxyethyl) phthalate (DMEP) acts by in vivo hydrolysis to 2-methoxyethanol (2-ME), also a known teratogen, which in turn is metabolized to methoxyacetic acid (MAA), the proximate teratogen. Teratological studies were conducted with Wistar rats, with the administration of these three agents on day 12 of gestation. On an equimolar dosage basis, DMEP, 2-ME, and MAA were equally potent, which is consistent with the hypothesis. There was a striking similarity in the defects produced by these agents, mainly hydronephrosis, heart defects, and short limbs and tails. In particular all three agents produced unusual heart defects (dilated ductus arteriosus and dilated aortic arch) not seen with other agents, as well as ventral polydactyly, a rarely seen defect, suggesting teratogenic action by a common mechanism or component; 4-methylpyrazole, an alcohol dehydrogenase inhibitor, provided significant protection against 2-ME. This combination of effects strongly suggests that following the administration of DMEP, 2-ME, or MAA, MAA is the proximate teratogen.

Abnormalities, Drug-Induced↗
PubMed1986

Major limb malformations following intrauterine exposure to ethanol: two additional cases and literature review.

Two children are reported in whom major limb malformations were identified and whose mothers had consumed large quantities of alcohol in the first trimester of pregnancy. In one there was complete amelia of the upper limbs, while the other had preaxial polydactyly of both hands. These cases, taken together with previously reported instances of major limb anomalies following intrauterine ethanol exposure, as well as animal investigations that have demonstrated virtually identical limb malformations following ethanol administration, suggest that maternal ethanol abuse may be casually related to these limb malformations. We suggest that interruption of blood supply to the developing limb may be caused by ethanol exposure and may result in all of the various limb malformations described.

Adult↗
PubMed1987

Dose- and stage-related sex difference in the incidence of cytosine arabinoside induced digit anomalies in the mouse fetus.

Pregnant mice of the Jc1:ICR strain were injected intraperitoneally with a single dose of 2.5, 5, or 10 mg/kg of cytosine arabinoside (Ara-C) on day 9.5 or 10.5 of gestation (dg). Mice were killed on 18.4 dg, and the incidences of digit anomalies were compared between male and female fetuses. In the group treated with 10 mg of Ara-C on 9.5 dg, oligodactyly of the hindlimbs was produced more frequently in male fetuses. In the group treated with 5 mg of Ara-C on 10.5 dg, oligodactyly of the forelimbs tended to occur more frequently in male fetuses. Also, in this group, oligodactyly of the hindlimbs occurred more frequently in male fetuses, whereas polydactyly occurred more frequently in female fetuses. The observed difference in the incidences of digit anomalies between male and female fetuses may be explained either in terms of the sex-related time lag in the critical period for digit development or by a probable sex difference in embryonic susceptibility to Ara-C.

Abnormalities, Drug-Induced↗
PubMed1988

Acetazolamide: maternal toxicity, pattern of malformations, and litter effect.

Thirty litters of C57BL 6J mice were administered intraperitoneally one of four doses (0, 500, 750, and 1,000 mg/kg maternal weight) of acetazolamide on day 9 of gestation. The fetuses were removed on day 18 and fixed, stained, cleared, and examined for the pattern of malformations. The forelimb postaxial limb deficiency was the most common abnormality, but forelimb postaxial polydactyly and a postaxial deficiency in the hindlimb were also observed. Males were significantly more likely to be malformed than females at all doses, in contrast to the predominance of females observed in rat fetuses exposed to acetazolamide (Scott et al.: Teratology 6:239-240, '73). The occurrence of limb malformations did not correlate with maternal weight loss, the birth weight of the fetus, or the position of the fetus in the uterus. A "litter effect" was demonstrated in that there was a nonuniform distribution of litters with different proportions of malformed fetuses.

Abnormalities, Drug-Induced↗
PubMed1988

Retinoic-acid-induced limb malformations resulting from apical ectodermal ridge cell death.

Pregnant C57Bl/6J mice were treated with single oral doses of 400 mg/kg 13-cis retinoic acid (RA, isotretinoin, Accutane) in sesame oil at 9 days, 12 hours postfertilization. Among the live 16-day fetuses from ten treated mothers, 46% (26/56) had limb malformations including small fifth digits, preaxial and/or postaxial oligodactyly, and preaxial or postaxial polydactyly. Fetuses with preaxial digit deficiencies also had absent or malformed radii. Scanning electron microscopic and light microscopic analyses of the sequence of developmental alterations leading to these malformations demonstrated abnormalities in the apical ectodermal ridge (AER). Excessive cell death in the AER of 27-30 somite embryos (12 hours after treatment) appears to play a major role in the pathogenesis of the limb malformations observed. Previous investigations of retinoid-induced limb malformations have concentrated on later exposure times. Evidence from this study in addition to that from previous teratologic and clinical investigations has led to the hypothesis that 13-cis RA results in excessive cell death in regions of programmed cell death and subsequent malformations of affected regions.

Animals↗
PubMed1990

Trisomy 13 in the fetus.

A significant number of fetuses with trisomy 13 are spontaneously or voluntarily lost before birth; however, very few such fetuses have been systemically autopsied. In the present study, ten trisomy 13 fetuses of 130-305 mm in crown-rump length, estimated gestational age from 108 days to 239 days, were examined following either karyotype or ultrasonographic diagnosis and voluntary termination. Mean maternal age was 35.1 years. The spectrum of anatomical features was similar to that observed in neonates or older infants with trisomy 13, namely, holoprosencephaly, cyclopia, microphthalmia, cleft palate and lip, cardiac defect, polydactyly, and cystic kidney. Kidney weights were significantly increased above normal in eight of nine fetuses. Histologically, the cortex of these kidneys showed increased mitotic activity and blastemic appearance, which extended deep into the medullary areas. The weights and histology of other organs were normal except for slight increases in spleen weight.

Body Weight↗
PubMed1991

Effects of isotretinoin (13-cis-retinoic acid) on the development of mouse limbs in vivo and in vitro.

Isotretinoin (13-cis-RA) is known to be teratogenic in humans and laboratory animals. The relatively low potency of 13-cis-RA in NRMI mice in comparison to the all-trans isomer has been proposed to be due to minimal transfer across the placenta (Creech-Kraft et al., '87). To further delineate the teratogenic potential of 13-cis-RA, a dose-response, temporal study was conducted in vivo and in vitro using submerged limb culture and image analysis evaluation of development. Dose-dependent embryotoxicity was produced by treatment on GD 7, while later treatments produced inconsistent effects on resorption rate and fetal weight. Treatment on either GD 7 or GD 8 produced a number of malformations in dose-dependent manner. Most common were tail and cleft palate defects, which were produced by 13-cis-RA on each of the days tested (GD 7-GD 11), with peak malformations occurring on GD 9 and GD 10 for tail and cleft palate, respectively. Most limb defects were produced after GD 10 and GD 11 exposure. The observed frequency of defects confirmed that in ICR mice 13-cis-RA is about 10-fold less potent than all-trans-RA as a limb teratogen (Kwasigroch and Kochhar, '80; Kochhar and Penner, '87). Effects observed via image analysis following maintenance of limbs in serum-free culture medium were dose dependent. Low dose treatment produced occasional polydactyly. The intermediate dose caused somewhat variable region-dependent increases in cartilaginous bone anlagen area. The high dose of 13-cis-RA produced irregular limb outlines, a reduction in bone anlagen area, and an inhibition of alcian blue staining of cartilage without affecting morphogenesis of bone anlagen. These results confirm that, when the effects of the administered doses are evaluated, 13-cis-RA is a much less potent teratogen in comparison to the all-trans isomer. More importantly, the results show that retinoids can enhance (at low and intermediate doses), depress (at high doses), or eliminate (high dose) chondrogenenic expression during limb morphogenesis in vitro. This indicates that retinoids such as 13-cis-RA can manipulate events in development in a variety of ways (i.e., produce malformations, interfere with chondrogenic expression without affecting morphogenesis, and stimulate growth) in a dose- and time-dependent manner. Although the ability of RA to act as a true morphogen has recently been questioned (Wanek et al., '91; Noji et al., '91), the results presented here support the position that RA can modulate the development of the limb (and probably other organ systems) in several vertebrate species.

Abnormalities, Drug-Induced↗
PubMed2004

Antenatal renal sonographic anomalies and postnatal follow-up of renal involvement in Bardet-Biedl syndrome.

OBJECTIVES: To describe an antenatal sonographic renal pattern encountered in Bardet-Biedl syndrome, a rare autosomal recessive disorder whose definitive diagnosis is often delayed, and to describe the evolution of the sonographic appearance of the kidneys after birth. METHODS: Among a large group of fetuses with hyperechoic kidneys, we retrospectively analyzed the prenatal sonographic findings and clinical and postnatal renal sonographic evolution of 11 patients who were found to be affected by Bardet-Biedl syndrome. RESULTS: All 11 fetuses presented enlarged homogeneously hyperechoic kidneys without corticomedullary differentiation. The diagnosis was established before birth in three fetuses thanks to their familial history. It was confirmed during childhood in the remaining eight based on the development of the classic features of the syndrome. In the postnatal period, the prenatal pattern persisted for a few months in all 11 cases. The sonographic aspects of the kidneys normalized in most cases between 1 and 2 years after birth. CONCLUSIONS: In affected families, the prenatal appearance of enlarged hyperechoic kidneys without corticomedullary differentiation should prompt a diagnosis of recurrence in the family of Bardet-Biedl syndrome, especially when polydactyly is present. In non-affected families, Bardet-Biedl syndrome should be included in the differential diagnosis whenever such an appearance is discovered in utero. The postnatal evolution of the renal sonographic findings is variable and normalization generally occurs by the age of 2 years.

Bardet-Biedl Syndrome↗
PubMed2005

Increased first-trimester fetal nuchal translucency thickness in association with chondroectodermal dysplasia (Ellis-Van Creveld syndrome).

Increased nuchal translucency thickness (NT) is an established sonographic marker of fetal chromosomal abnormality. Several structural fetal defects and genetic syndromes including a range of skeletal dysplasias have been reported in association with increased NT. We report the first case of fetal Ellis-Van Creveld syndrome presenting as raised fetal NT at 13 weeks' gestation. Ultrasonography at 18 weeks' gestation demonstrated a narrow thorax, marked shortening of the long bones with bowed femora and hexadactyly of hands and feet. Pregnancy was terminated at 23 weeks' gestation. The postmortem radiological examination revealed short and bowed long bones with rounded metaphyses, postaxial polydactyly of hands and feet, short ribs and narrow thorax. The acetabular roofs were horizontal with medial and lateral spurs. This case adds a further type of severe skeletal dysplasia to the list of genetic syndromes which may present as increased fetal NT in the late first trimester.

Adult↗