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PubMed1989

A 10- rather than 9-bp duplication associated with insertion of Tn5 in Escherichia coli K-12.

The composite transposable element Tn5, which is made up of two inverted IS50 elements surrounding genes encoding drug resistance, generally generates 9-bp duplications at the site of insertion. In our studies of three Tn5 insertion mutants at one location in the Escherichia coli chromosome, we have observed that one contains a duplication of 10 bp, while the other two have the usual 9-bp duplication. Three other insertion elements, IS1, IS4, and IS186, give variable-sized target site sequence duplications. We observed a similarity of amino acid sequence in a small region of the putative transposases among IS4, IS186, and Tn5 suggesting a conservation of function in this group of transposases.

Amino Acid Sequence↗

PubMed1992

Duplication mitosis in carcinoma.

As proposed in 'Duplication mitosis in epithelio-glandular tissue' (1), histological continuity is dependent on duplication mitosis. Organoid continuity of carcinomas is also likely to be dependent on duplication mitosis. Cancerous duplication may be due to deterioration of the maturation capacity of carcinoma cells and caused by a cellular abnormality that rejects the effect of the maturation factor. The fundamental therapeutic approach to carcinoma should be altered from one of cell destruction to one of inducing cell-phase maturation.

Cell Differentiation↗

PubMed1984

An unstable mutant gene of the am locus of Neurospora results from a small duplication.

We have cloned the unstable am mutant gene, am126, as well as the am gene from an am126 revertant. The mutation is a result of a 33-bp duplication that repeats a sequence starting 13 bp upstream of the 3' splice junction between intron 1 and exon 2 and extends 20 bp into exon 2. In addition, there is a G----A transition 2 bp upstream of the first copy of the duplicated sequence. In the revertant gene the wild-type sequence is precisely recovered, involving both the loss of the duplication and a reversion (A----G) of the associated transition. Our data suggest that only the more 5' of the two 3' splice junctions present in the duplicated version of the gene is used. This favors a 5'----3' scanning mechanism for exon splicing.

Base Sequence↗

PubMed1988

Duplicate breath testing: some statistical analyses.

Duplicate breath alcohol testing from each individual provides confidence in the results when reasonable agreement (i.e. +/- 0.02 g/210 L) is achieved. For this reason many jurisdictions require duplicate testing. The State of Washington has recently implemented an infrared breath testing program and now requires two breath samples from each individual. Statistical analysis of 1847 duplicate breath tests is presented. Three variables are analyzed: first alcohol result (ALC1), the absolute difference between the two breath samples (DIFFA), and the signed difference between the two breath samples (DIFFS). The first breath alcohol result ranged from 0.021 to 0.338 g/210 L with a mean of 0.157 g/210 L. The absolute difference ranged from 0.00 to 0.05 g/210 L. The signed difference ranged from -0.05 g/210 L to 0.05 g/210 L. The absolute difference was regressed upon the first alcohol result and resulted in poor linear correlation of r = 0.212. Duplicate breath test differences do not appear to be a function of subject's alcohol level, but rather of sample provision.

Adult↗

PubMed1990

Molecular characterization of Beckwith-Wiedemann syndrome (BWS) patients with partial duplication of chromosome 11p excludes the gene MYOD1 from the BWS region.

The molecular characterization of two patients with features of Beckwith-Wiedemann syndrome (BWS) and chromosome abnormalities is consistent with the association of this phenotype with a duplication of a portion of chromosome 11. Quantitative Southern blot analysis of DNA from patient A defines a large inherited duplicated segment of chromosome 11. For patient B, a de novo duplication of unknown origin has been shown to contain a segment of 11p15. This chromosome segment includes the genes for insulin-like growth factor 2, beta-hemoglobin, calcitonin A (CALCA), and parathyroid hormone (PTH). However, the myogenic differentiation factor, MYOD1, is not included in the duplicated segment. This demonstrates that MYOD1 is proximal to CALCA and PTH and excludes MYOD1 as the BWS gene. These data place the BWS gene distal to MYOD1 on 11p15.

Beckwith-Wiedemann Syndrome↗

PubMed1995

Gene duplication of the human peptide YY gene (PYY) generated the pancreatic polypeptide gene (PPY) on chromosome 17q21.1.

Neuropeptide Y (NPY), peptide YY (PYY), and pancreatic polypeptide (PP) are structurally related but functionally diverse peptides, encoded by separate genes and expressed in different tissues. Although the human NPY gene has been mapped to chromosome 7, we demonstrate here that the genes for human PYY and PP (PPY) are localized only 10 kb apart from each other on chromosome 17q21.1. The high degree of homology between the members of this gene family, both in primary sequence and exon/intron structure, suggests that the NPY and the PYY genes arose from an initial gene duplication event, with a subsequent tandem duplication of the PYY gene being responsible for duplication of the PYY gene being responsible for the creation of the PPY gene. A second weaker hybridization signal also found on chromosome 17q11 and results obtained by Southern blot analysis suggest that the entire PYY-PPY region has undergone a further duplication event.

Amino Acid Sequence↗

PubMed2004

Cdc28/Cdk1 regulates spindle pole body duplication through phosphorylation of Spc42 and Mps1.

Duplication of the Saccharomyces cerevisiae spindle pole body (SPB) once per cell cycle is essential for bipolar spindle formation and accurate chromosome segregation during mitosis. We have investigated the role that the major yeast cyclin-dependent kinase Cdc28/Cdk1 plays in assembly of a core SPB component, Spc42, to better understand how SPB duplication is coordinated with cell cycle progression. Cdc28 is required for SPB duplication and Spc42 assembly, and we found that Cdc28 directly phosphorylates Spc42 to promote its assembly into the SPB. The Mps1 kinase, previously shown to regulate Spc42 phosphorylation and assembly, is also a Cdc28 substrate, and Cdc28 phosphorylation of Mps1 is needed to maintain wild-type levels of Mps1 in cells. Analysis of nonphosphorylatable mutants in SPC42 and MPS1 indicates that direct Spc42 phosphorylation and indirect regulation of Spc42 through Mps1 are two overlapping pathways by which Cdc28 regulates Spc42 assembly and SPB duplication during the cell cycle.

Alleles↗

PubMed2004

Laparoscopic excision of a gastric duplication cyst detected on antenatal ultrasound scan.

The authors report a gastric duplication cyst detected antenatally and its subsequent laparoscopic removal at 2 months of age. Before birth, a cystic mass was detected behind the stomach on fetal ultrasound scan (US). After birth, an US, barium meal, nuclide scan, and cervical and thoracic vertebral x-rays suggested that the most probably diagnosis was a gastric duplication cyst. At 2 months of age, laparoscopic removal of the cyst was performed with closure of the muscle defect in the stomach wall. The patient was discharged 4 days later, feeding normally. Histology findings confirmed the diagnosis of a gastric duplication cyst. After the antenatal detection of a cyst behind the stomach, the laparoscopic removal of this gastric duplication in a 2 month old was accomplished without complications. This appears to be the first reported case using this type of procedure in an infant.

Brain Diseases↗

PubMed2006

Triplication of colon with diphallus and complete duplication of bladder and urethra.

Gastrointestinal duplications are a common type of congenital anomaly usually restricted to one part of the gut. Triplication of colon is a rare variation of duplication of the hindgut. Hindgut duplications are commonly associated with anomalies of other derivatives of the cloaca, namely, the lower genitourinary system. Here, we describe a child with triplication of colon with associated duplication of bladder and urethra and diphallus. The child described here is the only reported survivor with triplication.

Colon↗

PubMed2007

Congenital double anus with total colon duplication: a case report.

Cases of congenital double anus are very rare. The number of cases of hindgut duplication of all kinds is slightly higher, and some series include patients with genitourinary and genitalia duplications but with a single anus. However, double termination with tubular duplication is rarely heard of. We report on the case of a patient with 2 well-formed ani, total colon duplication, and 2 vaginas.

Abnormalities, Multiple↗

PubMed2005

Experiences in kidney transplantation with duplicated ureters.

INTRODUCTION: The purpose of this study was to evaluate the complications of duplicated ureters in renal transplant recipients. METHODS: Between 1983 and 2004, 12 patients (median age 34 years) received renal transplants from donors with duplicated ureters. In four patients the ureter to bladder anastomoses were performed separately according to the method described by MacKinnon, including two cases transplanted with ureteral catheters because of narrow widths. In the following cases of eight duplicated ureters an anastomosis was performed between the distal part of each ureter to form a common ureteral ostium, which was connected to the urinary bladder. A ureteral catheter was used to the splint ureterovesical anastomosis. RESULTS: No graft loss to ureteral complications was observed. There was no ureteral necrosis in the postoperative period. No clinical symptoms of ureteral junction obstruction were revealed after removing the ureteral catheter. By ultrasound examination four patients showed a slight temporary pyelocaliectasis was observed and four patients developed temporary urinary fistulas. CONCLUSION: Our ureterocystoneostomy procedures with duplicated ureters were safe and useful in kidney transplantation.

Adult↗

PubMed1986

Bladder duplication with one exstrophy and one cloaca.

Bladder duplication is a rare anomaly. Less than 100 cases of all types have been described in the literature. When duplication of the bladder occurs, it has previously been described as a mirror image or as a septate bladder. A newborn female presented with what appeared to be a complete bladder exstrophy, a large ruptured omphalocele with perforated large bowel, an imperforate anus, and a bifid clitoris. Urine was seen emanating from various sites: the bladder mucosa, the mucous fistula constructed at the time of the colostomy, and the left hemiclitoris. The anatomic puzzle was resolved when multiple studies disclosed the problem to be a bladder duplication. The bladder on the anterior abdominal wall was exstrophied, the intraabdominal bladder was a cloaca, and the left hemiclitoris contained a phallic urethra, which drained the intraabdominal bladder. Total correction with normal function was obtained. This patient demonstrates that bladder duplication may present in various ways.

Abnormalities, Multiple↗

PubMed1997

Continuous communicating esophageal and gastric duplication.

Duplications of the esophagus or stomach alone are infrequent, and complete foregut duplication has only rarely been described. Most combined esophagogastric duplications present within the first year of life, and if communication with the normal alimentary tract does occur, it does so only either above or below the diaphragm. This report illustrates a case of continuous duplication of the esophagus and stomach with communication to the normal alimentary tract at both proximal and distal ends. Operative management and a review of the literature and embryology are described.

Esophagus↗

PubMed1997

Bronchogenic cysts and esophageal duplications: common origins and treatment.

BACKGROUND/PURPOSE: Bronchogenic cysts and esophageal duplications are usually considered as separate foregut malformations. Yet, both are thought to arise from the same embryological event, division of the embryonic foregut, and they share common histological characteristics, often making their clinical differentiation difficult. METHODS: A retrospective review of the cases of 68 children treated at a single institution between 1937 and 1995 was performed. Thirty children were girls (44%) and 38 were boys (56%). Ages ranged from newborn to 24 years. Complete records were available in all children. Fourteen of these 68 children were asymptomatic. RESULTS: Respiratory (54%) or gastrointestinal (13%) symptoms were the most frequent presenting problems. The majority of children were treated by resection of the cyst (52 of 68; 76%), while 9 of 68 (13%) required lobectomy for intraparenchymal lesions. Three children underwent marsupialization, with all of these children requiring additional surgery for recurrent disease. Five children (5 of 68; 7%) had multiple cysts. The mortality rate from this series was 10% (7 of 68). Two deaths were caused by perioperative exsanguination, one related to bleeding from a cyst lined with gastric mucosa with subsequent ulceration and hemorrhage into the esophagus. Two deaths occurred secondary to septic complications, one from an esophageal leak and the other from an intraparenchymal abscess. Two deaths were caused by respiratory failure; one was unrelated (SIDS). The majority of cysts found on histological review were lined by respiratory epithelium or bronchial glands (51 of 68; 75%). Gastrointestinal epithelium was present in cysts of nine children, only two of which were clinically diagnosed as esophageal duplications. Twenty-one cases (21 of 68; 31%) were classified as esophageal duplications based on the intramural location of the cyst, yet 15 of 21 (71%) contained respiratory epithelium, substantiating the hypothesis of the common origin of these lesions. CONCLUSIONS: The histological similarity and anatomic proximity of the "bronchogenic cysts" and the intramural "esophageal duplications" supports their common origin. The possible complications of bleeding, ulceration, infection, and obstruction of the esophagus or airway, should generally lead to prompt resection.

Adolescent↗

PubMed1998

Enteric duplications of the pancreatic head: definitive management by local resection.

BACKGROUND/PURPOSE: Enteric duplications can occur throughout the entire alimentary tract. When they occur in the pancreatic head, they present a formidable challenge in both diagnosis and treatment. Surgical management has ranged from simple drainage to local excision or radical resection (eg, Whipple procedure). The authors propose that with identification of the local anatomic relationships, definitive management can be achieved by complete local resection of the cyst mucosa. METHODS: The authors have treated four patients, ages 13 months to 4 years for enteric duplication cysts within the pancreatic head. RESULTS: Clinical presentations were quite varied, including pancreatitis (n = 2), gastritis (secondary to increased production of gastrin), and recurrent pleural effusion with high amylase content. Two of the four cysts had been drained initially using Roux-en-Y cystenterostomies. Our preoperative imaging studies included abdominal ultrasonography, endoscopic retrograde cholangiopancreatography (ERCP), angiography, computerized tomography (CT) or magnetic resonance imaging (MRI) scanning. When necessary intraoperatively, ultrasonography was used for cyst localization and transduodenal pancreatography to define precise ductal relationships. All four duplication cysts were completely excised, including two that communicated directly with the main pancreatic duct. One of the latter extended into the pleural cavity and required a thoracotomy for complete excision. Pathological exam of the excised cysts demonstrated gastric, duodenal, or respiratory mucosa. All four patients have remained entirely asymptomatic during a follow-up of 2 to 7 years postoperatively. CONCLUSION: The authors conclude that complete local resection of enteric duplication cysts in the pancreatic head can be performed for definitive management, avoiding the complications of more radical procedures.

Anastomosis, Roux-en-Y↗

PubMed1999

Guided versus unguided mandibular movement for duplicating intraoral eccentric tooth contacts in the articulator.

STATEMENT OF PROBLEM: The extent to which intraoral excursive tooth contacts are duplicated correctly in the articulator is constantly being investigated. PURPOSE: This study evaluated whether data from unguided or guided hinge axis movement are superior in duplicating excursive tooth contacts. MATERIAL AND METHODS: Intraoral records of tooth contacts from intercuspal position to 4 mm protrusion and laterotrusion were obtained from 50 subjects by using occlusogram wax. These movements were simulated in a SAM2 "P" articulator using horizontal condylar inclination and Bennett angle from recorded guided and unguided mandibular movements. Occlusograms were compared with contacts generated by the articulator. RESULTS: On average, the articulator duplicated approximately 73% of intraoral protrusive and 81% of intraoral laterotrusive contacts for up to 4 mm of movement, using either data from unguided or guided movements. Both movements yielded identical means and no significant difference of duplicated contacts. However, individual differences scattered within approximately +/-32%. CONCLUSION: Exclusive recommendation of guided movement can be questioned for accurate imitation of dynamic tooth contacts. In addition to the type of movement, other factors must be detected to enhance articulator adjustment and workings.

Adolescent↗

PubMed1978

Reflux in complete duplication in children.

Reflux is the most common abnormality associated with complete ureteral duplication. Several authors have emphasized early surgical correction of reflux when it occurs in duplicated systems. because of a negligible success rate in non-operative therapy. Our practice has been to judge an orifice with reflux on its own merit, that is position, appearance and submucosal tunnel length. Realizing that this philosophy is not in total agreement with most of the literature on reflux in ureteral duplication we have reviewed 59 cases to ascertain whether our non-operative approach has justification. In this study early operation was elected in 61 per cent of those patients with reflux in association with total duplication. However, in 48 per cent of patients followed with non-operative surveillance reflux has either stopped spontaneously or is medically stable.

Child↗

PubMed1975

Tubular duplication of the rectum with a rectourethral fistula.

An infant with pneumaturia and fecaluria was found to have a rectal duplicatation with a fistula between the duplicated rectum and the urethra. Rectal duplication, although rare, should be considered in cases of bizarre lower bowel symptoms in children. Correction in our case was effected by exclusion of the duplicated segment along with removal of its mucosal lining and division of its urethral fistula. The termination of the duplicated rectum in the urinary tract, as in cases of imperforate anus, suggests a related embryologic mechanism for the 2 types of anomalies.

Colon↗