Extrinsic fetal akinesia and skeletal development: a study in oligohydramnios sequence

Long-bone morphometry and cephalometry were performed in 13 newborns with oligohydramnios sequence (OS) in order to establish whether or not skeletal changes existed in extrinsic fetal akinesia similar to those observed in the fetal akinesia deformative sequence (FADS) (i.e., hypoplastic long bones and micrognathia). Oligohydramnios sequence was caused by bilateral renal agenesis in five cases and obstructive uropathy in eight cases. Twenty-one stillborns and newborns who had died from conditions other than renal anomalies or congenital malformations were used as controls. Normal longitudinal and periosteal long-bone growth and absence of micrognathia were found in OS patients. Skeletal differences between FADS and OS may be explained not only by timing, duration, and degree of reduced motility but also, and more importantly, by the normal muscular stress in OS patients.     

Mutation analysis of CHRNA1, CHRNB1, CHRND, and RAPSN genes in multiple pterygium syndrome/fetal akinesia patients

Multiple pterygium syndromes (MPS) comprise a group of multiple congenital anomaly disorders characterized by webbing (pterygia) of the neck, elbows, and/or knees and joint contractures (arthrogryposis). MPS are phenotypically and genetically heterogeneous but are traditionally divided into prenatally lethal and nonlethal (Escobar) types. Previously, we and others reported that recessive mutations in the embryonal acetylcholine receptor g subunit (CHRNG) can cause both lethal and nonlethal MPS, thus demonstrating that pterygia resulted from fetal akinesia. We hypothesized that mutations in acetylcholine receptor-related genes might also result in a MPS/fetal akinesia phenotype and so we analyzed 15 cases of lethal MPS/fetal akinesia without CHRNG mutations for mutations in the CHRNA1, CHRNB1, CHRND, and rapsyn (RAPSN) genes. No CHRNA1, CHRNB1, or CHRND mutations were detected, but a homozygous RAPSN frameshift mutation, c.1177-1178delAA, was identified in a family with three children affected with lethal fetal akinesia sequence. Previously, RAPSN mutations have been reported in congenital myasthenia. Functional studies were consistent with the hypothesis that whereas incomplete loss of rapsyn function may cause congenital myasthenia, more severe loss of function can result in a lethal fetal akinesia phenotype.     

Long bone development in extrinsic fetal akinesia: an experimental study in rat fetuses subjected to oligohydramnios.

The transverse growth of long bones during intrauterine development was studied in rat fetuses subjected to experimental oligohydramnios in order to determine whether the skeletal changes, if any, in extrinsic fetal akinesia were similar to those observed in curarized rat fetuses with the fetal akinesia deformation sequence. Oligohydramnios was induced by daily extraction of amniotic fluid from day 17 of gestation until term. Experimental fetuses were compared with a sham-operated control group. The total area and perimeter, the absolute and relative amount of periosteum and bone trabeculae, the major and minor axes, and the elongation factor were measured in histological cross sections of the femoral metaphysis and diaphysis with an IBAS 1 image analysis system. Rat fetuses in the experimental group showed multiple articular contractures, redundant skin, and lung hypoplasia, a phenotype consistent with the oligohydramnios sequence. No alterations in femoral shape and transverse growth of the metaphysis and diaphysis were noted in these fetuses. These results suggest that the main mechanical factor related to fetal bone modeling is muscular strength, while motion would be mainly involved in fetal joint development.     

Pre- and postnatal findings in Pena Shokeir I syndrome: case report and a review of the literature

The Pena Shokeir type I syndrome is considered to be a lethal disorder in most cases. Infrequently, some of the affected children may reach the age of 1 year and beyond. When there is a history of another affected sib, the entity can be suspected prenatally. It is an uncommon autosomal recessive disorder. Out of 33 reported infants reviewed by us, six survived the neonatal period; among a further 27 cases, reported more recently, none survived the neonatal period. The clinical findings at birth are multiple and involve mainly the musculoskeletal and respiratory systems, accompanied by characteristic facial changes. The possibility of a primary hereditary malformation affecting the motor neuron cells of the spinal cord is postulated with the subsequent changes representing a fetal akinesia deformation sequence.     

The fetal akinesia sequence: pitfalls and difficulties in genetic counseling

In this paper, we review the difficulties of genetic counseling in the fetal akinesia sequence. The ongoing progress in the nosological subclassification, thanks to the increasing number of fetopathological studies, is the basis and a condition sine qua non for accurate genetic counseling.     

The fetal akinesia deformation sequence. A fetopathological approach

In this paper we review the present knowledge on the etiological factors and pathogenetic mechanisms of the fetal akinesia deformation sequence, based on a fetopathological approach. Special attention is given to two sever, lethal subgroups i.e. the Pena-Shokeir I syndrome and the lethal multiple pterygium syndrome.     

Acetylcholine receptor pathway mutations explain various fetal akinesia deformation sequence disorders

Impaired fetal movement causes malformations, summarized as fetal akinesia deformation sequence (FADS), and is triggered by environmental and genetic factors. Acetylcholine receptor (AChR) components are suspects because mutations in the fetally expressed gamma subunit (CHRNG) of AChR were found in two FADS disorders, lethal multiple pterygium syndrome (LMPS) and Escobar syndrome. Other AChR subunits alpha1, beta1, and delta (CHRNA1, CHRNB1, CHRND) as well as receptor-associated protein of the synapse (RAPSN) previously revealed missense or compound nonsense-missense mutations in viable congenital myasthenic syndrome; lethality of homozygous null mutations was predicted but never shown. We provide the first report to our knowledge of homozygous nonsense mutations in CHRNA1 and CHRND and show that they were lethal, whereas novel recessive missense mutations in RAPSN caused a severe but not necessarily lethal phenotype. To elucidate disease-associated malformations such as frequent abortions, fetal edema, cystic hygroma, or cardiac defects, we studied Chrna1, Chrnb1, Chrnd, Chrng, and Rapsn in mouse embryos and found expression in skeletal muscles but also in early somite development. This indicates that early developmental defects might be due to somite expression in addition to solely muscle-specific effects. We conclude that complete or severe functional disruption of fetal AChR causes lethal multiple pterygium syndrome whereas milder alterations result in fetal hypokinesia with inborn contractures or a myasthenic syndrome later in life.     

Mutations in FLVCR2 Are Associated with Proliferative Vasculopathy and Hydranencephaly-Hydrocephaly Syndrome (Fowler Syndrome)

Proliferative vasculopathy and hydranencephaly-hydrocephaly syndrome (PVHH), also known as Fowler syndrome, is an autosomal-recessively inherited prenatal lethal disorder characterized by hydranencephaly; brain stem, basal ganglia, and spinal cord diffuse clastic ischemic lesions with calcifications; glomeruloid vasculopathy of the central nervous system and retinal vessels; and a fetal akinesia deformation sequence (FADS) with muscular neurogenic atrophy. To identify the molecular basis for Fowler syndrome, we performed autozygosity mapping studies in three consanguineous families. The results of SNP microarrays and microsatellite marker genotyping demonstrated linkage to chromosome 14q24.3. Direct sequencing of candidate genes within the target interval revealed five different germline mutations in FLVCR2 in five families with Fowler syndrome. FLVCR2 encodes a transmembrane transporter of the major facilitator superfamily (MFS) hypothesized to be involved in regulation of growth, calcium exchange, and homeostasis. This is the first gene to be associated with Fowler syndrome, and this finding provides a basis for further studies to elucidate the pathogenetic mechanisms and phenotypic spectrum of associated disorders.     

Diagnosis of fibromatosis colli by fine needle aspiration (FNA) cytology

This study presents eight cases of fibromatosis colli accurately diagnosed by FNA cytology. Fibromatosis colli is a rare fibroblastic lesion that manifests in the sternocleidomastoid muscle during the first to second months after birth. The tumours varied in size from 1 to 3 cm and engaged the lower, middle as well as the upper part of the sternocleidomastoid muscle. The FNA cytology smears showed mostly mature fibroblasts in a background of pink granular material and fragments of striated muscle fibres with degeneration. The cytological presentation together with the typical clinical setting will allow a definitive and accurate diagnosis, avoiding surgery.     

Mutations in KLHL40 Are a Frequent Cause of Severe Autosomal-Recessive Nemaline Myopathy

Nemaline myopathy (NEM) is a common congenital myopathy. At the very severe end of the NEM clinical spectrum are genetically unresolved cases of autosomal-recessive fetal akinesia sequence. We studied a multinational cohort of 143 severe-NEM-affected families lacking genetic diagnosis. We performed whole-exome sequencing of six families and targeted gene sequencing of additional families. We identified 19 mutations in KLHL40 (kelch-like family member 40) in 28 apparently unrelated NEM kindreds of various ethnicities. Accounting for up to 28% of the tested individuals in the Japanese cohort, KLHL40 mutations were found to be the most common cause of this severe form of NEM. Clinical features of affected individuals were severe and distinctive and included fetal akinesia or hypokinesia and contractures, fractures, respiratory failure, and swallowing difficulties at birth. Molecular modeling suggested that the missense substitutions would destabilize the protein. Protein studies showed that KLHL40 is a striated-muscle-specific protein that is absent in KLHL40-associated NEM skeletal muscle. In zebrafish, klhl40a and klhl40b expression is largely confined to the myotome and skeletal muscle, and knockdown of these isoforms results in disruption of muscle structure and loss of movement. We identified KLHL40 mutations as a frequent cause of severe autosomal-recessive NEM and showed that it plays a key role in muscle development and function. Screening of KLHL40 should be a priority in individuals who are affected by autosomal-recessive NEM and who present with prenatal symptoms and/or contractures and in all Japanese individuals with severe NEM.     

The use of the coefficient of agreement and likelihood ratio test to examine the development of the tympanic plate using a known-age sample of fetal and infant skeletons

Previous attempts to use the development of the tympanic plate as an aging standard for fetal and infant cranial remains have either produced only a developmental sequence (Anderson, 1960), or a sequence for which age has been estimated using another independent aging standard (Weaver, 1979). Following an evaluation of the first three stages of development of the tympanic plate using a known-age sample of fetal and infant skeletal remains, a simple test of inter-observer agreement, Cohen's coefficient of agreement (Cohen, 1960), is demonstrated using the developmental stages.     

Fibromatosis colli in infants. A cytologic study of eight cases

OBJECTIVE: To review eight cases of fibromatosis colli and assess their cytomorphologic features. STUDY DESIGN: Cytologic smears from eight patients diagnosed as having fibromatosis colli on fine needle aspiration cytology were reviewed. RESULTS: Cytologic features of fibromatosis colli are bland-appearing fibroblasts and degenerative atrophic skeletal muscle in a clean background. Besides these, we found a large number of muscle giant cells; numerous bland, bare nuclei; and parallel clusters of fibroblasts. Collagen was seen in all cases. CONCLUSION: A confirmatory, noninvasive diagnosis of fibromatosis colli can be made by fine needle aspiration cytology alone; invasive diagnostic and therapeutic measures are best avoided. Excision biopsy may not be necessary and should be reserved for cases with a strong clinicopathologic suspicion of malignancy.     

Beta-endorphin induced akinesia in rats: effect of apomorhine and alpha-methyl-p-tyrosine and related modifications of dopamine turnover in the basal ganglia

β-Endorphin (amino acid sequence 61–91 of β-lipotropin) administered intraventricularly at a dose of 13 n moles in rat induced akinesia and loss of corneal reflex. Apomorphine (20 mg/kg) which had been injected subcutaneously 20 minutes after the administration of β-endorphin fully reversed akinesia and elicited characteristic stereotyped behavior. During complete disappearance of akinesia, the corneal reflex was found to be still absent. Apomorphine (5 mg/kg) only partially reversed akinesia. Pretreatment with α-methyl-p-tyrosine (α-MT, 250 mg/kg) potentiated the effect of β-endorphin upon muscle rigidity. In a biochemical study, rats received β-endorphin (15 n moles) 60 minutes before sacrifice. Concentrations of dopamine (DA) and norepinephrine (NE) were not altered in any brain regions. A significant increase in concentrations of 5-hydroxytryptamine was obtained in the midbrain. In a DA and NE turnover study, rats received α-MT (250 mg/kg) 4 hours prior to β-endorphin and were sacrificed 60 minutes later. β-Endorphin partially corrected the decreased concentrations of DA induced by α-MT in the midbrain. A similar tendency toward correction of the decreased DA concentrations was observed in the striatum. The concentrations of NE decreased by α-MT in the midbrain, striatum and hypothalamus were not modified by β-endorphin     

The human cadherin-10 gene: complete coding sequence, predominant expression in the brain, and mapping on chromosome 5p13-14.

In a quest for novel cadherin gene family members in the human dbEST database, an interesting EST clone was identified and chosen for subsequent analysis. Using the technique of 5' rapid amplification of cDNA ends, we isolated the complete coding sequence and a large part of the UTRs of a novel gene. The sequence appeared to correspond to the human cadherin-10 gene, whose sequence was only partially known before. The expression pattern of this cadherin was found to be largely brain-specific, with additional expression in both adult and fetal kidney, and with minor expression in prostate and fetal lung. By FISH analysis the genomic location was determined at human chromosome 5p13-14, which is nearby the reported positions of the human cadherin-6, -12, and cadherin-14 (CDH18) genes. Cadherin-10 shows high relationship to the human cadherin-6 gene.     

Laryngeal atresia sequence as part of the DiGeorge developmental field defect.

The subject of the present report is a male newborn with laryngeal atresia (LA) type I, giving rise to a malformation sequence consisting of overdistended polyalveolar lungs and nonimmune fetal hydrops with massive ascites. The infant was chromosomally normal and the first child of consanguineous parents. Retention of liquid secreted by the fetal lungs in utero was the pathogenetic mechanism, responsible for the LA sequence. The LA was part of a complex constellation of anomalies, compatible with the DiGeorge developmental field defect.     

Cloning, sequencing and analysis of a gene encoding Escherichia coli proline dehydrogenase

Abstract Using a genomic subtraction technique, we cloned a DNA sequence that is present in wild-type Escherichia coli strain CSH4 but is missing in a presumptive proline dehydrogenase deletion mutant RM2. Experimental evidence indicated that the cloned fragment codes for proline dehydrogenase (EC 1.5.99.8) since RM2 cells transformed with a plasmid containing this sequence was able to survive on minimal medium supplemented with proline as the sole nitrogen and carbon sources. The cloned DNA fragment has an open reading frame of 3942 bp and encodes a protein of 1313 amino acids with a calculated M _r of 143 808. The deduced amino acid sequence of the E. colli proline dehydrogenase has an 84.9% homology to the previously reported Salmonella typhimurium putA gene but it is 111 amino acids longer at the C-terminal than the latter.     

Testosterone synthesis in vitro by the fetal testis of the guinea pig

Synthesis and secretion of testosterone by testes of guinea pig fetuses were studied in organ culture. The amount of testosterone secreted into the culture medium was estimated by radio-immunoassay. It was demonstrated that testosterone was already secreted by testes explanted at 25 days. The amount of testosterone secreted during the first day in culture by testes from fetuses of different ages (25–30 days) increased with fetal age. The amount of testosterone extracted from fetal guinea pig testes at ages used for explantation (25–30 days) were much lower than the amount secreted during the first 24 hours in culture. During subsequent days in culture, an increase in the amount of testosterone secreted was observed only for testes explanted at 25 days. The amount secreted by testes from older fetuses (26–30 days) stayed constant or decreased. Aminogluthetimide phosphate (100 μM) decreased significantly testosterone secretion by testes explanted at 25 days.These findings indicate that the capacity for biosynthesis of testosterone is present in fetal guinea pig testes at 25 days and increases during the subsequent days.     

Effects of taurine and γ-aminobutyric acid on akinesia and analgesia induced by D-Ala2-Met-enkephalinamide in rats

Effects of taurine or γ-aminobutyric acid (GABA) on akinesia and analgesia induced by D-Ala²-Met-enkephalinamide were investigated in rats. Administration of taurine (dose range: 2.375×10^?2 M–9.5×10^?2 M/10 μl) into the left lateral ventricle 10 min prior to the injection of D-Ala²-Met-enkephalinamide (50 μg/10 μl) produced a dose-dependent reduction in the duration of akinesia and to some extent of analgesia, as estimated at 30 min and 60 min following the enkephalinamide injection; at the first estimation-time (10 min), taurine did not alter the duration of akinesia or that of analgesia. The median effective dose (ED₅₀) for akinesia determined at 60 min after D-Ala²-Met-enkephalinamide was 5 times greater and that for analgesia assessed at the same time was 1.7 times greater in taurine-treated rats than the respective doses in control animals. Administration of GABA under similar experimental conditions produced a dose-dependent reduction in the duration of analgesia from the initial estimation time (10 min) following the injection of D-Ala²-Met-enkephalinamide. The ED₅₀ for analgesia determined at 30 min after D-Ala²-Met-enkephalinamide was 3 times greater in GABA-treated rats than in control animals. Unlike the effects of taurine, GABA did not alter the duration of akinesia. Neither the duration of akinesia nor that of analgesia was modified by taurine or GABA alone in rats tested 9 min after the injection of each amino acid. These findings suggest that taurine may promote a recovery from both akinesia and analgesia, while GABA decreases only the analgesia induced by D-Ala²-Met-enkephalinamide.