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At least 1,387 records · Page 77Linked to original sources
PubMed1991

Structure and promoter activity of the LpS1 genes of Lytechinus pictus. Duplicated exons account for LpS1 proteins with eight calcium binding domains.

The LpS1 genes of the sea urchin Lytechinus pictus are activated early in development in aboral ectoderm cells. They therefore have ontogenic properties similar to their counterparts in Stronglyocentrotus purpuratus, the Spec genes. Both gene families encode proteins belonging to the calmodulin superfamily as evidenced by the presence of distinct EF-hand (helix-loop-helix) domains. The presence of eight EF-hand domains in LpS1 proteins suggests that the LpS1 genes arose from a duplication of an ancestral Spec-like gene. The LpS1 genes were further analyzed to increase our understanding of the mechanisms underlying their evolution and activation in aboral ectoderm cells. Genomic DNA blot analysis showed two LpS1 genes, LpS1 alpha and LpS1 beta, which did not appear to be closely linked. LpS1 genomic clones were isolated by screening an L. pictus genomic library with an LpS1 cDNA clone, and partial gene structures for both LpS1 alpha and LpS1 beta were constructed. These revealed internal duplication of the LpS1 genes that accounted for the eight EF-hand domains in the LpS1 proteins. Duplication of exon 1 in both genes suggested four different LpS1 proteins could be derived from the LpS1 genes. Primer extension to map the transcriptional initiation sites of the LpS1 genes and sequencing analysis showed there was little in common among the 5'-flanking regions of the LpS1 and Spec genes except for the presence of a binding site for the transcription factor USF. A sea urchin gene-transfer expression system showed that 762 base pairs (bp) of 5'-flanking DNA and 17 bp of 5'-untranslated leader sequence of the LpS1 beta gene were sufficient for correct temporal and spatial expression of reporter chloramphenicol acetyltransferase and lacZ genes in sea urchin embryos. Deletions at the 5' end to either 511 or 368 bp resulted in a 3-4 fold decrease in chloramphenicol acetyltransferase activity and disrupted the exclusive activation of the lacZ gene in aboral ectodermal cells. Based on a lineage analysis among the LpS1 and Spec gene families and other related genes, we propose a model in which LpS1 genes evolved from a series of duplications of an ancestral Spec-like gene.

Amino Acid Sequence↗
PubMed1990

[Duodenal duplication cyst].

Duodenal duplication cysts are rare and are usually found in neonates or young children who present with obstructive symptoms. It accounts for 4-12% of all duplications in the gastrointestinal tract. The rate of other developmental abnormalities has been reported as high as 38%. In few instances have duodenal duplication cysts been described in adults. A case of duodenal duplication cyst in a 46-year-old woman is presented. The diagnosis was established preoperatively by computerized tomography and ultrasound examination.

Cysts↗
PubMed1990

[Duplication of the intestinal tract].

Twelve duplications of the alimentary tract in eleven children are reviewed. There was a predominance of the spheric type of duplication as well as the neonatal group of children with clinical sign of tumour in most cases. There were no major problems in resection of spheric duplications but tubular type cases afforded different procedure in each case. Three cases with associated atresias were noted. There was one death related to gastric duplication.

Colon↗
PubMed1990

Partial gene duplication involving exon-Alu interchange results in lipoprotein lipase deficiency.

Major structural rearrangements are uncommon causes of mutation in human genetic diseases. We have previously described that a significant proportion of unrelated patients of western European descent who are deficient in lipoprotein lipase (LPL) activity have a major structural rearrangement in the LPL gene. Here we report the detailed characterization of this mutation. We show that this rearrangement is due to a duplication of approximately 2 kb which results from juxtaposition of intron 6 to a partially duplicated exon 6. We have sequenced both the junction fragment of this duplication and the corresponding wild-type regions and have found that the breakpoint in intron 6 is associated with the simple repeat found at the 3' end of an Alu element. The breakpoint within exon 6 shows no homology to this simple repeat. This result both suggests that this interchange arose as a nonhomologous recombination event and shows that such events resulting in duplication which occur in normal gene evolution may also lead to genetic disease. Cloning of the junction fragment has allowed synthesis of appropriate primers for rapid screening for this rearrangement in other families with LPL deficiency.

Blotting, Southern↗
PubMedDate not supplied

Three faces of midgut duplication.

This is an analysis of three unusual cases of gastrointestinal duplications seen over a two year period. They were all males aged eight and 48 hours, and 4 1/2 years. Two had cystic duplications; in one of them it was associated with a partially fixed cecum resulting in a volvulus, while in the second the duplication occurred in association with duodenal atresia and jejunal deletion. The third patient had a tubular malformation involving distal jejunum, whole of the ileum, and right side of the colon as far as its transverse level. It was also associated with duodenal stenosis and rectal atresia. Two cystic duplications had muscular coats separate from the normal bowel permitting complete excision. Clinical presentation and pathological anatomy are briefly considered and aspects of management are discussed.

Child, Preschool↗
PubMed1990

[Duplication of the stomach and intestine in children].

The authors observed 25 children at the age of from 2 mos to 14 years with the different forms of gastric and intestinal duplication. Cystic forms of duplication (16 cases) were manifested mainly by the symptoms of obstruction of the alimentary canal, diverticular duplication (3) was complicated by profuse bleeding, tubular duplication (6) was more often revealed in the rectum (4). Correct diagnosis before the operation was established in 5 patients. Choice of a method for operation is individual. The results of treatment are favourable.

Adolescent↗
PubMed1989

Duplication of stomatodeal structures: report of three cases with literature review and suggestion for classification.

Three cases of duplications of stomatodeal structures are reported. One had an accessory mouth that could move simultaneously with his mouth at sternal notch. Another had a teeth-bearing bony mass at left maxilla with excessive upper lip and a false pouch. The third had an excessive upper lip, upper jaw with teeth, and hard and soft palate. The literature is reviewed, and a classification is suggested: type I, a duplicated mouth; type II, duplication of maxilla-upper lip or mandible-lower lip complex; and type III, centrally located, poorly developed lip-jaw duplication.

Abnormalities, Multiple↗
PubMed1989

[Duplication of the urethra in boys].

Duplicity of the urethra as an isolated unit is found only in men. According to the classification of Williams and Kenawi of 1975 most frequently sagittal duplicity is involved. As to the site of the orifice of the ectopic urethra different types are found - epispadic, hypospadic, spindle-shaped type of urethra and Y-shaped duplicity. The authors discuss three patients where they diagnosed and treated three different types of duplicity.

Child↗
PubMedDate not supplied

[Theoretical analysis of the DNA duplication mechanisms in the prokaryotic genomes on the basis of repeats].

In the present work a theoretical analysis of the molecular mechanisms on duplications emergence in the genomes of prokaryotes on the basis of direct repeats has been carried out. The correlations obtained have shown, that the duplication rate depends on such parameters as the distance between repeated regions, repeats nucleotide composition and the number of homology damages in them. It has been revealed that the rate of duplications decreases more readily than the deletion rate upon the growth of the distance between the repeats. Such prevalence of deletions over duplications must lead to the elimination of various types of direct repeats from the prokaryotic genomes in the course of their evolution.

Cells↗
PubMed1988

[Intrathoracic gastric duplication with intrapulmonary abscesses and perforation into the bronchial system--pathologico-anatomic peculiarities and diagnostic problems].

Gastric and enteric cysts represent genuine duplications. With regard to their genesis opinions are divided. These duplications may perforate into the lung parenchyma and/or the bronchial system, giving rise to specific symptoms. The only possible therapy is complete extirpation. The intrapulmonary metastases are drained and aspirated and can be cured without loss of lung tissue. A report is given on a thoracic cystic gastric duplication with haemorrhagic inflammation of the mucous membrane associated with erosions in a 8-week old boy. Clinically, the duplication was reflected by poor general health, dyspnea and tachypnea. The perforation into the bronchial system caused respiratory insufficiency. Using antibiotic therapy, immune substitution and surgery in combination, the boy was cured. The morphological findings, causative embryological factors, and diagnostic possibilities and problems are discussed.

Bronchi↗
PubMed1987

Multiple esophageal duplication cysts.

During thoracic exploration for resection of an esophageal duplication cyst, a second such cyst was encountered and removed. Although the association of esophageal duplication cysts with other intestinal duplications has been described, to our knowledge this is the first reported case of multiple esophageal duplication cysts.

Esophageal Cyst↗
PubMedDate not supplied

[Adenocarcinoma in a cystic duplication of the ileum].

A case of adenocarcinoma arising in a cystic duplication of the ileum of a 34 year old woman is described. Only one case of adenocarcinoma in ileal duplication has been recorded previously. The adenocarcinoma arose from gastric mucosa of a tubular duplication. In this case the adenocarcinoma arose from primitive type intestinal mucose in a cystic duplication.

Adenocarcinoma↗
PubMed1986

Is duplicate testing for prothrombin time and activated partial thromboplastin time necessary?

To evaluate the necessity of duplicate testing for prothrombin times (PTs) and activated partial thromboplastin times (APTTs), the range of differences between duplicate sample results was analyzed on a widely used automated photo-optical coagulation instrument. Specimens with coagulation test times ranging from normal to threefold above the reference range were included. Of 1,610 PTs and 1,023 APTTs, approximately 95% of duplicates differed by 0.2 s or less and 2.0 s or less, respectively. Approximately 99% of PTs and APTTs differed by 0.4 s or less and 4.0 s or less, respectively; there were three PT and 16 APTT specimens whose duplicates differed by a greater time interval and also by more than 5% of the mean. Thus, PT and APTT testing on automated instrumentation is very precise, but occasional inaccurate single measurements could lead to errors in diagnosis or therapy.

Blood Coagulation Tests↗
PubMed1979

Duplicated axolotl regenerates.

Three series of palette stage regenerates were prepared by amputating both arms of juvenile axolotls in the mid-forearm, above the elbow, or close to the shoulder. Within each series, excised regenerates were replaced in their original orientation (as a control) or rotated at 90 degrees intervals about the proximodistal axis, or were transplanted to the contralateral arm with identical rotations. Control grafts occasionally caused the formation of a single extra digit. All experimental rotations provoked duplicate or triplicate structures, ranging from accessory digits to extra forearms. Shoulder level grafts were subject to a pronounced correctional derotation and yielded a variable proportion of duplications. Forearm and elbow-level rotations invariably yielded duplications, which therefore result from an axial discrepancy rather than complete axial opposition between graft and host. These results are incompatible with the clockface model of positional information and demand a modification of other current models. The recorded frequency and orientation of duplications suggest that a limb contains at least two polarized transverse axes which cannot be respecified during regeneration. A substantial discrepancy on either axis reduces the normal regulative interaction between graft and host, allowing either of them to regenerate independently.

Ambystoma↗
PubMedDate not supplied

[Ileal duplication in adults. Value of 99m pertechnetate scintigraphy].

Duplications of the small bowel are an uncommon group of congenital malformations whose symptoms rarely occur in adults. We report the case of a 21 year-old man who suffered during four years from symptoms related to the ulceration of ectopic gastric mucosa in an ileal duplication (spontaneously resolving peritonitis, pelvic abscess, recurrent gastrointestinal bleeding and chronic abdominal pain). Radiological and endoscopic explorations and a first laparotomy failed to provide the diagnosis. 99m pertechnetate (99mTcO4) scintigraphy demonstrated ectopic gastric mucosa and guided the radiological detection of an ileal ulceration. Injection of 99mTcO4 during a second laparotomy located the ectopic gastric mucosa at the level of a tumefaction found on the mesenteric side of the terminal ileum. Duplication was only recognized at pathological examination of the ileal resection. This case emphasizes the need to evoke a duplication in clinical circumstances like those described in this patient as well as the usefulness of 99mTcO4 in the diagnosis of such a malformation.

Adult↗
PubMed1980

Duplicate exstrophy of the bladder.

Duplicate exstrophy is a very rare variant of the exstrophy complex. Treatment is gratifying, because the patients have normal internal urogenital structures. Two different cases of duplicate exstrophy are presented. One is completely similar to the type, described by Marshall and Muecke, of which now 9 cases have been reported. It is suggested that the other, together with 4 earlier reported cases, belongs to a different type of duplicate exstrophy. The embryological mechanism responsible for this type is probably a coincidence of 1) duplication of cloacal structures and 2) exstrophy of one of the bladders.

Abdominal Muscles↗
PubMed1984

Duodenal duplication presenting as relapsing pancreatitis in an adult.

The first case of relapsing acute pancreatitis due to a tubular duodenal duplication is reported. The duplication is believed to have filled with secretions and intermittently impinged on and obstructed the pancreatic ductular system producing a clinical picture of relapsing acute pancreatitis. The increased pressure within the duplication also produced pressure necrosis of the mucosa lining the duplication with resultant hemorrhage and iron-deficiency anaemia. The diagnosis was made preoperatively with the aid of ERCP.

Acute Disease↗