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We report a gastric duplication in a 23-year-old man. The case is unique because the stomach is the rarest location for enteric duplication, the duplication almost never occurs in adults, and the duplication consisted exclusively of pancreatic tissue. This extreme example illustrates the close embryologic and anatomic association between stomach and pancreas. A case is made for the use of the general term of foregut duplication to avoid confusing nomenclature.
Radial polydactyly, a common congenital problem, most often occurs as thumb duplication. It appears in pentadactylous, polydactylous, and hypoplastic hands and is simulated by complex syndactyly. Classically, there are three categories for radial polydactyly: severe hypoplasia, partial duplication, and total duplication (easily confused with pseudoduplication). The common second category is subcategorized by Wassel's seven types. Management techniques vary with these classifications. Until a decade ago, the standard recommendation was simple excision of one of the duplicates. Problems of deformity, instability, and weakness became apparent, and reconstructive options were developed. Review of a series of 54 duplicate thumbs, all surgically treated, reflects the changing pattern of reconstruction. With current techniques, good results are usual, although secondary reconstructive procedures may be required. Simple excision is seldom indicated. Combination procedures, involving core tissues of bone, joint, and tendon or peripheral tissues--neurovascular, subcutaneous, and skin--or sometimes all of these, are preferred for reconstruction. The major current problem is to achieve the maximal good result with a minimal number of surgical operations.
In order to understand the coordinate regulation between the alpha-like and beta-like globins during the developmental switches in hemoglobin synthesis, we have studied the rabbit alpha-like globin gene family. A cluster of six linked genes arranged 5'-zeta 1-alpha 1-theta 1-zeta 2-zeta 3-theta 2-3' has been isolated as a set of overlapping clones from a library of rabbit genomic DNA. Blot-hybridization analysis of genomic DNA not only confirms this linkage arrangement but also reveals the presence of additional zeta and theta genes. We propose that this gene cluster was generated by a block duplication of a set of alpha-like genes; the proposed duplication unit is zeta-zeta-alpha-theta. Further duplications of a zeta-zeta-theta set are also proposed to have occurred. As expected for a duplicated locus, the rabbit alpha-like gene cluster contains long blocks of internal homology. The Z homology block is about 7.2 kilobase pairs long and contains the zeta genes; the T homology block is about 4.7 kilobase pairs long and contains a theta gene. Surprisingly, both Z and T homology blocks are flanked by a common junction sequence (J) which contains a region very similar to the 3'-untranslated sequence of an alpha-globin gene. Analysis of the J sequences suggests a recombination mechanism by which the alpha gene could have been deleted from the second set of genes in the cluster (zeta 2-zeta 3-theta 2). The relationships among the genes in characterized alpha-like gene clusters in mammals are summarized. The rabbit gene cluster differs from those of other mammals principally in the loss of a gene orthologous to the human psi alpha 1 and in the block duplication of the zeta-zeta-alpha-theta gene set.
Many tissues from wild type mice express cytosolic malic enzyme activity and contain two mRNAs (2.0 and 3.1 kilobases (kb)) that encode a single 64-kDa malic enzyme subunit polypeptide. MOD-1 null mutant mice lack cytosolic malic enzyme activity but express 2.5- and 3.6-kb mRNAs that hybridize with wild type malic enzyme cDNAs and are induced in liver by a starvation/carbohydrate refeeding regimen. To investigate the basis of the MOD-1 null mutation, a lambda gt11 cDNA library was constructed using mRNA from the livers of induced MOD-1 null mice as a template. A recombinant phage with a 2-kb insert was isolated by screening with wild type malic enzyme cDNA probes. The subcloned insert exhibited an atypical (non-wild type) restriction pattern and was subjected to sequence analysis. MOD-1 null malic enzyme cDNA contains an internal tandemly duplicated sequence that corresponds to nucleotides 1027-1548 in the coding region of wild type murine malic enzyme cDNA (Bagchi, S., Wise, L. S., Brown, M. L., Bregman, D., Sul, H. S., and Rubin, C. S. (1987) J. Biol. Chem. 262, 1558-1565). An open reading frame is retained throughout the duplicated sequence. The discovery of a 522-nucleotide in-frame duplication accounts for the increased size of MOD-1 null malic enzyme mRNAs and suggests that a variant malic enzyme polypeptide that is 19 kDa larger than the wild type subunit might be found in mutant mice. Western immunoblot analysis disclosed that MOD-1 null liver cytosol contains an 82-kDa protein that is recognized by anti-malic enzyme antibodies. Under stringent conditions, an anti-sense 32P-oligonucleotide that spans the abnormal junction between the reiterated sequences hybridized with the 2.5 and 3.6-kb MOD-1 null malic enzyme mRNAs but failed to form stable complexes with wild type malic enzyme mRNAs. Thus, both MOD-1 null malic enzyme mRNAs contain the duplication deduced from cDNA sequence analyses. The MOD-1 null mutation might originate from an unequal crossover between homologous regions of two different introns in the malic enzyme gene, thereby causing the duplication of one or more exons.
Primary tumors of the esophagus are extremely rare in children. A common periesophageal mass in children is duplication. It constitutes only 0.5 to 2.5% of all esophageal lesions usually diagnosed in infancy or early childhood. Duplication of the esophagus may be diagnosed on examination by the emergency department (ED) physician when it produces symptoms or when it is inadvertently found on a chest radiograph. The duplication may produce acute gastrointestinal symptoms such as vomiting and dysphagia or respiratory symptoms such as cough, wheezing, or dyspnea. Currently the examination of choice for evaluation of esophageal duplication is a barium swallow. However, computed tomography (CT) has the advantage over conventional diagnostic procedures, since it demonstrates the cystic nature of the mass and its relationship to adjacent structures in a noninvasive manner. An esophageal duplication has a well-marginated spherical mass contiguous with the esophagus, with preserved surrounding fat planes, and numbers of 15 to 30 Hausenfield units (HU) on CT. We are reporting three cases of this anomaly as demonstrated by CT.
The duplication of the urethra is a rare but well described anomaly. The authors report two more cases which contribute to illustrate the classification and the problems met in this condition. The classification proposed by D.I. Williams and M.M. Kenawi has been adopted. They distinguish 5 types of urethral duplications: epispadiac, hypospadiac (complete or incomplete forms), spindle urethra, bifid urethras (H-type) with an accessory pre-anal branch, and finally collateral duplications. The first reported case is a complete epispadial duplication type. The second case is a incomplete hypospadial duplication type, associated with late complications due to the unrecognized valve effect by the mucosal folds at the junction between the two urethras. The diagnosis, the treatment and the embryology are discussed in both cases.
A 2 1/2-year-old girl was seen with an upper abdominal mass. Evaluation by abdominal ultrasonography, esophagography, upper gastrointestinal series, and computerized axial tomography suggested the possibility of duplication of the esophagus, stomach, and duodenum. Surgery revealed a triplication of the esophagus with a gastric duplication, which was resected. The patient recovered and greatly increased her weight-for-age percentile. Of the theories proposed to explain gastrointestinal duplications, the split notochord hypothesis most closely fits this patient's anomalies. It is unusual for a patient with a gastrointestinal duplication to develop symptoms after the first year of life. This is the first report of a triplication of the esophagus with a gastric duplication.
The clinical and pathological findings of two children with thoracoabdominal enteric duplications are described in detail. In addition, 23 case reports are reviewed. The majority of duplications communicated with the gastrointestinal tract below the diaphragm, but in one case, reported here, the duplication communicated with the cervical esophagus. In infants these duplications most often present with respiratory symptoms, whereas older children more typically have pain and melena. If possible the entire duplication should be removed during one operation.
It is a general rule that of two complementary Drosophila imaginal disc fragments, one regenerates and the other duplicates. This paper reports an investigation of an exception to this rule. Duplicating fragments from the periphery of the wing disc which lacked presumptive notum were found to regenerate notum structures during and after duplication. The propensity for this was greatest in fragments lying close to the presumptive notum, with the exception of a fragment confined to the posterior compartment, which did not regenerated notum. Structures were added sequentially, and regeneration stopped once most of the notum was present. These results are not easily explained by the polar coordinate model, which states that regeneration cannot occur from duplicating fragments. Since compartments appear to be involved in this type of regeneration as in others, it is suggested that a new type of model is required, one which permits simultaneous regeneration and duplication, and assigns a major role to compartments.
A 32 week, small for gestational age neonate was found to have partial duplication of the short arm of chromosome 2 (2p23 to pter). This duplication was due to a paternal balanced translocation [46,XY,t(2;20)(p23;q13)]. Peculiar facies with prominent eyes, low set ears and anteverted nostrils was apparent. A PDA with congestive heart failure occurred in the first weeks of life. The patient also had a marked diastasis recti, hemivertebrae, long tapering fingers and rocker bottom feet. The propositus was similar to the 14 cases of 2p duplication previously reported. It appears that duplication of the distal end of 2p (2p23 to pter), with or without deletion, should be classified as duplication (2p) syndrome.
The case of a 22-year-old patient with a thoracoabdominal duplication of the alimentary tract is described. The chest radiograph, with a large cyst in the posterior mediastinum and vertebral abnormalities and a barium swallow showing the abdominal part of the duplication, were diagnostic. At operation a malrotation of the midgut was found and the duplication was resected, leaving esophagus and small bowel intact. An explanation for association of the two malformations - vertebral abnormalities and malrotation - was sought in the literature, particularly that concerning embryogenesis. The following conclusions were reached: 1. Duplications of the alimentary tract are a heterogeneous group with three different embryological faults in development. 2. According to the so-called notochordal theory, vertebral abnormalities and malrotation of the midgut are usual and should be expected in thoracoabdominal duplications of the alimentary tract.
Gastric duplications are unusual congenital anomalies that often require surgical treatment. Pyloric duplications are particularly rare; few are reported in the English literature. This article reviews the literature on pyloric duplications and describes a pyloric duplication associated with hypertrophic pyloric stenosis in a 5-week-old child and a duplication that recurred 7 years later.
Charcot-Marie-Tooth disease type 1A (CMT1A) is a hereditary peripheral neuropathy with a genetic locus on chromosome 17p11.2. The majority of patients carry a duplicated DNA segment that encompasses the gene PMP22, which encodes a peripheral myelin protein. PMP22 is the crucial gene involved in the pathogenesis of CMT1A. Molecular diagnosis of CMT1A requires detection of this duplicated segment. Existing methods for detection of the duplication are laborious and time consuming. We have developed a set of polymorphic (AC)n repeat markers (contained within the duplication) for use in the polymerase chain reaction, which give a high probability of detecting three unique alleles in affected individuals. This test detected 85% of a panel of 52 CMT1A patients in which the duplication had previously been demonstrated.
The type VI variant of the Ehlers-Danlos syndrome (EDS) is a recessively inherited connective-tissue disorder. The characteristic features of the variant are muscular hypotonia, kyphoscoliosis, ocular manifestations, joint hypermobility, skin fragility and hyperextensibility, and other signs of connective-tissue involvement. The biochemical defect in most but not all patients is a deficiency in lysyl hydroxylase activity. Lysyl hydroxylase is an enzyme that catalyzes the formation of hydroxylysine in collagens and other proteins with collagen-like amino acid sequences. We have recently reported an apparently homozygous large-duplication rearrangement in the gene for lysyl hydroxylase, leading to the type VI variant of EDS in two siblings. We now report an identical, apparently homozygous large duplication in an unrelated 49-year-old female originally analyzed by Sussman et al. Our simple-sequence-repeat-polymorphism analysis does not support uniparental isodisomy inheritance for either of the two duplications. Furthermore, we indicate in this study that the duplication in the lysyl hydroxylase gene is caused by an Alu-Alu recombination in both families. Cloning of the junction fragment of the duplication has allowed synthesis of appropriate primers for rapid screening for this rearrangement in other families with the type VI variant of EDS.
Rearrangements of the ALL-1 gene by reciprocal translocations involving chromosome band 11q23 are frequently associated with human acute leukemia. We have previously reported the detection of ALL-1 gene rearrangements in adult patients with acute myeloid leukemia lacking cytogenetic evidence of 11q23 translocations. These included 2 of 19 patients with normal karyotypes as well as 3 of 4 patients with trisomy 11 as a sole cytogenetic abnormality. Rearrangement of the ALL-1 genes in two of the patients with trisomy 11 was shown to result from a direct tandem duplication of a portion of the gene spanning exons 2-6. Here we report the characterization of the ALL-1 gene rearrangement in one of the previously reported acute myeloid leukemia patients with a normal karyotype. ALL-1 rearrangement in this patient results from a direct tandem duplication of a portion of the gene spanning exons 2-8. RNA polymerase chain reaction and DNA sequence analysis show that the partially duplicated ALL-1 gene is transcribed into mRNA capable of encoding a partially duplicated protein. Sequence analysis of the genomic fusion region provides evidence for Alu-mediated homologous recombination as a mechanism for partial duplication of the ALL-1 gene.
Congenital gastrointestinal duplications are uncommonly diagnosed in adult patients, and generally present as a cystic or occasionally tubular malformation. The duplication is composed of a smooth muscle wall continuous with the muscle layer of the intestinal wall and an inner mucosal lining. From December 1988 to May 1994, five patients were operated for gastrointestinal tract duplications [esophageal (1), gastric (2), duodenal (2)]. Duplications were symptomatic in three patients, and discovered incidentally in the other two. The diagnosis was established by ultrasonography (3 patients) and computed tomography (one patient). One female presented an adenocarcinoma arising in an esophageal duplication and died one year after surgical resection. Because of potential malignant transformation, these malformations must be resected. Preoperative diagnosis is important for conservative resection, except in the presence of malignancy when resection must be curative.
We studied phenotypic heterogeneity in 18 Japanese patients with Charcot-Marie-Tooth disease type 1A (CMT1A) with PMP-22 gene duplication, together with heterogeneity of duplication size. In order to detect the duplication of PMP-22 gene region, the PMP-22 cDNA and a polymorphic marker VAW409R3 were used as probes for Southern blot analysis. As the clinical phenotypes, we assessed the degree of foot deformity, muscular weakness and atrophy, tendon reflexes, sensory impairment and electrophysiologic and sural nerve biopsy findings. Although the degree of muscular weakness and atrophy was slightly more severe in the advanced age, there was a patient with calf hypertrophy in the older age or a patient with marked muscular atrophy of the leg in the younger age. The incidence of foot deformities and sensory impairment was high and these phenotypes did not relate to aging. Diminished or absent tendon reflexes and slowing of motor conduction velocities were commonly seen, but the motor conduction velocity varied greatly among the patients. The clinical phenotypes were extensively variable among the CMT 1A patients with the same gene mutation of PMP-22 gene duplication, suggesting that there is a factor other than PMP-22 gene duplication, which influences phenotypic manifestation in CMT 1A.
The aim of this study was to investigate if four duplicate blood pressure (BP) remeasurements are sufficient for diagnosing hypertension in potentially hypertensive subjects. The subjects were 99 outpatients who were included on the basis of elevated diastolic (95 < or = DBP < or = 115 mm Hg) or systolic (160 < or = SBP < or = 200 mm Hg) BP. After inclusion all patients underwent nine subsequent duplicate BP measurements over a period of 7 months. None of the patients received hypotensive drug treatment during the study. Between the first (initial) and second measurements there were significant reductions in systolic (161.0-152.5 mm Hg) and diastolic (101.5-97.1 mm Hg) BPs (P < 0.01). Differences between the subsequent measurements were not statistically significant. A linear regression analysis proved that the "conceptual average BP' (the average of the last five visits) which was chosen as the reference value was stable. The decline of standard deviations of differences between two, three and four duplicate remeasurements on one hand, and the reference value on the other was found to be strikingly small. After four duplicate remeasurements, there was misclassification in 56% (systolic) and 38% (diastolic). We conclude that the numbers of two, three or four BP measurements recommended by international guidelines for diagnosing hypertension are too low. Even after four duplicate remeasurements a considerable amount of misclassification remains.