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PubMedDate not supplied

[Tubular duplication of the colon: a case report and review of the literature].

Among Gastrointestinal Duplications, colonic duplications are the less common. The case presented here consist of a duplication of the transverse colon, difficult to diagnose, which had abdominal distension as the main symptom. A 4-year-old child was referred to the Unity of Pediatric Surgery, Hospital de Base, Brasilia, DF with a history of progressive abdominal distension. Plain X-Rays of the abdomen demonstrated a large fecaloma, which demanded removal. A Barium Enema was done suggesting Congenital Megacolon. A rectal biopsy was performed under general anesthesia, demonstrating normal ganglion cells. Medical treatment was instituted for chronic constipation in the Pediatric Gastroenterology clinic. The patient returned three months later with the same complaints. A new rectal biopsy was done; normal ganglion cells were described, ruling out Hirschsprung's disease. The parents were told to insist on the medical treatment diets. Four years later the patient was seen in the Emergency Room with signs and symptoms of low intestinal obstruction. Exploratory Laparotomy was undertaken as an emergency and the findings were complete volvulus of the large bowel involving the transverse colon up to the splenic flexure, demonstrating a large duplication of the transverse colon. A resection of the duplication and end-to-end colonic anastomosis was performed with an uneventful postoperative care. Discharged on excellent conditions.

English Abstract↗

PubMed2004

Playing polo in G1: a novel function of polo-like kinase-2 in centriole duplication.

Centrosomes contain a pair of centrioles that duplicate once during the cell cycle to give rise to two mitotic spindle poles, each containing one old and one new centriole. Centrosome duplication initiates at the G(1)/S transition in mammalian cells, and is completed during S and G(2) phase. The localization of a number of protein kinases to the centrosome has revealed the importance of protein phosphorylation in controlling the centrosome duplication cycle. Recent studies have shown that polo-like kinase-2 is required for centriole duplication in mammalian cells. In this article I discuss the implication of these findings to our current understanding of centrosome duplication.

Animals↗

PubMed2005

Loading and unloading: orchestrating centrosome duplication and spindle assembly by Ran/Crm1.

The cell cycle is an intricate process of DNA replication and cell division that concludes with the formation of two genetically equivalent daughter cells. In this progression, the centrosome is duplicated once and only once during the G1/S transition to produce the bipolar spindle and ensure proper chromosome segregation. The presence of multiple centrosomes in cancer cells suggests that this process is mis-regulated during carcinogenesis. This suggests that certain factors exist that license the progression of centrosome duplication and serve to inhibit further duplications during a single cell cycle. Recent studies suggest that the Ran/Crm1 complex not only regulates nucleocytoplasmic transport but is also independently involved in mitotic spindle assembly. Factors that are capable of interacting with Ran/Crm1 through their nuclear export sequences, such as cyclins/cdks, p53 and Brca1/2, may potentially function as centrosome checkpoints akin to the G1/S and G2/M checkpoints of the cell cycle. Our recent findings indicate that nucleophosmin, a protein whose trafficking is mediated by the Ran/Crm1 network, is one of such checkpoint factors for maintaining proper centrosome duplication. We propose that Ran/Crm1 may act as a 'loading dock' to coordinate various checkpoint factors in regulating the fidelity of centrosome duplication during cell cycle progression, and the disruption of these processes may lead to genomic instability and an acceleration of oncogenesis.

Animals↗

PubMed2002

Sonographic detection of gallbladder duplication: two cases discovered in utero.

OBJECTIVE: To report the in utero diagnosis of a duplicated gallbladder. METHODS: Obstetric sonography was performed at 2 separate referral centers. A comprehensive level 11 examination was performed at each center. RESULTS: In both cases, a duplicated gallbladder was detected in utero without the presence of other anatomic abnormalities. CONCLUSIONS: Gallbladder duplication, although uncommon, should be considered when an additional cystic structure is seen in the right upper quadrant. Recognition of the presence of a duplicated gallbladder, a relatively benign condition, prevents invoking a more serious diagnosis, such as a choledochal or duodenal duplication cyst.

Adult↗

PubMedDate not supplied

Reduction of irrational drug duplication in geriatric nursing homes.

The reduction of irrational drug duplication by rigorous drug regimen review, in-service education, and physician acceptance of consultant pharmacist recommendations in a 72-bed geriatric long-term-care facility is described. In decreasing order of frequency of duplication, laxatives, analgesics, NSAIDs, diuretics, hypnotics, antipsychotics, KC1 supplements, hematinics/vitamins, antacids, and antinauseants and antidiarrheals were the drug classes most often duplicated. Apparent reasons for the duplications were confusion over the term "of choice," physician convenience, failure to review medication orders actively, and individual nurse preferences for different agents in each duplicated drug class.

Aged↗

PubMed1999

A new mechanism of acquisition of drug resistance by partial duplication of topoisomerase I.

Topoisomerase (topo)-I targeting antitumor agents are very effective in vivo against various human cancers. The indolocarbazole compound 6-N-formylamino-12,13-dihydro-1,11-dihydroxy-13-(beta-D-glucopyranosyl)- 5H-indolo[2,3-alpha]pyrrolo-[3,4-c]carbazole-5,7(6H)-dione (NB-506) is a potent inhibitor of the religation step of topo I reaction, like camptothecin (CPT). We established a NB-506-resistant cell line from murine leukemia cell line P388. This resistant cell line, P388/F11, exhibited 73-fold higher resistance to NB-506 and 3.5-fold higher cross-resistance to CPT than the parental cell line. No induction of cleavable complex formations induced by NB-506 and CPT were detected by K-SDS precipitation assays in P388/F11 cells. Analysis of nuclear extracts from P388/F11 cells revealed that the relaxation activity of topo I was one-quarter of that of the parental cells, and that the activity was resistant to induction of DNA cleavage by these drugs. Furthermore, Western blot and Northern blot analyses showed the expression of an abnormal-sized 170-kDa topo I protein and its 6.0-kb transcript and the absence of the normal topo I protein and transcript in P388/F11 cells. Analyses of the structure of the abnormal topo I transcript by reverse transcription-PCR and direct sequencing methods revealed that a large portion of the gene from codon 21 to codon 609 was duplicated in its coding region. This internal duplication resulted in in-frame fusion and, thus, production of a partially duplicated protein of 1357 amino acids. Finally, we expressed and purified the recombinant P388/F11 topo I in a baculovirus system. P388/F11 topo I showed similar catalytic activity to wild-type topo I, but reduced sensitivities to NB-506 and CPT. These results show that the altered sensitivity of duplicated topo I is involved in the NB-506 resistance of P388/F11 cells and indicate a novel resistant mechanism which involves duplication of the topo I gene.

Animals↗

PubMed1999

Duplications of the gastrointestinal tract.

BACKGROUND: Gastrointestinal duplications are rare, benign congenital lesions that may occur at any location along the alimentary tract and generally require surgical intervention. Presenting symptoms may be quite varied even among patients with the same anomaly. OBJECTIVE: To review the clinical presentation of gastrointestinal duplications and present our experience with such lesions over the past decade. METHODS: The records of all patients treated for gastrointestinal duplications at a tertiary hospital during 1987 through 1996 were collected, and relevant published literature reviewed. RESULTS: In the nine patients with gastrointestinal duplications, six were in the small bowel and one each in the cecum, colon and esophagus. Presenting clinical features were varied and often subtle. Perinatal ultrasonography, radioscintography and computerized tomography were useful in some cases, while in others the correct diagnosis was established only at surgery. CONCLUSIONS: Alimentary tract duplications are uncommon, and may present as solid or cystic tumors, intussusception, perforation or gastrointestinal bleeding. A high index of suspicion is required when dealing with such cases. Appropriate investigations, including imaging techniques, should be directed toward adequate and planned surgery.

Digestive System Abnormalities↗

PubMed1999

Reconstructing the duplication history of a tandem repeat.

One of the less well understood mutational transformations that act upon DNA is tandem duplication. In this process, a stretch of DNA is duplicated to produce two or more adjacent copies, resulting in a tandem repeat. Over time, the copies undergo additional mutations so that typically, multiple approximate tandem copies are present. An interesting feature of tandem repeats is that the duplicated copies are preserved together, making it possible to do "phylogenetic analysis" on a single sequence. This involves using the pattern of mutations among the copies to determine a minimal or a most likely history for the repeat. A history tries to describe the interwoven pattern of substitutions, indels, and duplication events in such a way as to minimize the number of identical mutations that arise independently. Because the copies are adjacent and ordered, the history problem can not be solved by standard phylogeny algorithms. In this paper, we introduce several versions of the tandem repeat history problem, develop algorithmic solutions and evaluate their performance. We also develop ways to visualize important features of a history with the goal of discovering properties of the duplication mechanism.

Algorithms↗

PubMed2002

Extravesical common sheath detrusorrhaphy (ureteroneocystotomy) and reflux in duplicated collecting systems.

PURPOSE: Various surgical approaches have been used for treatment of vesicoureteral reflux in uncomplicated duplicated collecting systems. We retrospectively evaluated our success with extravesical common sheath detrusorrhaphy in such a setting. MATERIALS AND METHODS: Between 1990 and 1997, unilateral and bilateral extravesical nondismembered detrusorrhaphy was performed in 24 and 19 patients, respectively, with 51 duplicated collecting systems, including 8 bilateral, for management of vesicoureteral reflux. Vesicoureteral reflux was present in the moieties of ipsilateral duplicated kidney in 2 patients, and bilateral reimplantation was performed in 2 who had a history of contralateral vesicoureteral reflux that resolved. Patient age ranged from 1 to 16 years (median 3.67). Followup ranged from 36 to 114 months (median 86), and included cystourethrography and renal ultrasound. RESULTS: Vesicoureteral reflux resolved in all but 1 duplicated renal moiety, which was a success rate of 98%. In this patient the persistent reflux resolved by 16 months postoperatively on conservative treatment. There were no intraoperative complications and all patients resumed spontaneous voiding before discharge home. No postoperative obstruction of the involved kidney or de novo contralateral reflux developed in any patient. CONCLUSIONS: Common sheath ureteral reimplantation with extravesical detrusorrhaphy can be successfully used to treat vesicoureteral reflux in uncomplicated duplicated collecting systems. This approach demonstrates excellent long-term surgical outcome with minimal perioperative morbidity.

Adolescent↗

PubMed2001

[Cystic duplication of the esophagus].

UNLABELLED: Duplication is defined as the presence of a complete or partial double structure, with a variable length. In esophagus, duplications, diverticuli and cysts might be manifestations of the same embriologic defect. The most common is the Cystic Duplication of the esophagus (CDE), which represents the esophageal duplication, either spherical or tubular, with squamous or columnar epithelium, and a double muscular layer. CLINICAL CASE: male, 38 years old with no previous relevant data, and sudden, complete and persistent post ingestion aphagia, intense presternal pain, and a 12 Kg. weight loss in 15 days. Endoscopy showed unsurpassable stenosis of the lower third of the esophagus, with normal mucosa. Total esophagectomy and replacement with a gastric tube, was performed. He had a good postoperative course. PATHOLOGY: A total esophagectomy open specimen showing a cystic structure at the posterior wall was submitted, which showed a thick, muscular-like wall and hemorrhagic internal surface. Microscopically it had a pseudostratified columnar, ciliated epithelium, alternating with sloughed hemorrhagic areas, fibrosis and stromal siderophagi Leiomuscular double-layered wall. CDE is very infrequent, and is the second most frequent after leiomiomas as a benign esophageal mass. From 10 to 15% of all digestive duplications take place at the esophagus. There are different theories to explain its origin. Differential diagnosis must be made mainly with brochogenic cyst, generally anterior and with cartilage. Treatment is surgical.

Adult↗

PubMedDate not supplied

Duplication of transverse colon: report of one case.

Alimentary tract duplications are very rare, with a reported incidence of 1 in 5000 live births. However, it rarely affects the transverse colon. We reported a case of duplication of the transverse colon in a 12-year-old boy with an unusual presentation mimicking megacolon. Barium enema revealed a large sac with massive fecal material retention in the left side of abdomen. Barium filling of the sac displacing bowel loops was noted on the post-evacuation film. He received a segmental resection of the transverse colon including the duplicated colon and end-to-end colo-colostomy. Pathology revealed whole muscle layer of colon compatible with duplication. No other associated anomaly was noted in this case. The case demonstrates three relatively uncommon presentations, including transverse colon location, late manifestation and dilated colon mimicking megacolon radiologically. It also emphasizes that barium enema with post-evacuation film aids in the preoperative diagnosis of duplication.

Child↗

PubMed2003

Upper urinary tract tumor in a duplicated collecting system: report of three cases and review of the literature.

Despite the common anomaly of a duplicated collecting system in the urinary tract, urothelial cancer in a duplicated collecting system is a rare occurrence. Herein, we present 2 cases of renal pelvis tumor and 1 case of a ureter tumor which coexisted with a duplicated collecting system. One of the renal pelvis tumors developed bilateral transitional cell carcinoma within the bilateral duplicated pelvis. This has not been reported previously. The tumor of the ureter in the latter case was located at the junction site of the bifurcation. This finding is consistent with the postulation that urine reflux chronically irritates the distal segment of a duplicated ureter, rendering this segment susceptible to malignant change. Recurrence of the tumor is frequently observed, which necessitates an early diagnosis and radical treatment.

Aged↗

PubMed2004

[Unequal crossing over as the pathway of adaptive homologous recombination between the direct DNA repeats in tandem duplications of Escherichia coli].

Homologous recombination between direct DNA repeats within the extended tandem duplications in E. coli results from unequal sister-chromosome exchanges. This conclusion follows from the observations on the segregation of completely or partly homozygous diploid segregants by heterozygous duplications. The formation of diploid segregants with preserved heterozygosity for the unselected markers could also result from "symmetrical" intrachromosomal recombination. Analysis of the segregant genotypes, however, confirmed their formation via unequal crossing over. The data obtained indicated that in tandem duplications segregation of diploid recombinants of different types was preceded by the formation of triplications as the products of unequal sister-chromosome exchanges. In heterozygous duplications, unequal crossing over is manifested as a highly frequent adaptive exchange, providing the survival of the most part of the duplication-carrying cells on selective medium. It is suggested that adaptive mutagenesis can be the consequence of unequal sister crossing over.

Crossing Over, Genetic↗

PubMed2004

Adenocarcinoma arising in rectal duplication cyst: case report and review of the literature.

Duplication cyst of the gastrointestinal (GI) tract is a rare congenital anomaly, and rectal duplication cysts comprise a small fraction these cases. Most patients present for the first time in adulthood, and the origin of rectal duplication cysts is unclear. Prior series document malignant transformation in approximately 20 per cent of cases. The following case report describes a carcinoma arising in a rectal duplication cyst. Given the lack of data demonstrating adequate control for patients with adenocarcinoma arising in a rectal duplication cyst and our experience with this patient, we recommend all patients undergo multidisciplinary evaluation prior to any therapy.

Adenocarcinoma, Mucinous↗

PubMed2005

Adult gastric duplication cysts: a case report and review of literature.

In this report, we present the rare case of a 53-year-old white female with a gastric duplication cyst. Diagnosis was made with a combination of CT scan and endoscopic ultrasound. The cyst was removed by using a seromuscular incision and enucleation. A review of English literature was performed to help define the etiology, workup, and treatment of adult patients. Theories of origin include embryologic enteric diverticula, incomplete notochordal plates separation, and embryonic longitudinal folds that fuse with a bridge. The essential features of duplication are that the cyst wall is contiguous with the stomach, is surrounded by smooth muscle, has a common blood supply, and is lined with epithelium. Few duplication cysts are diagnosed after the age of 12 and in adults present a diagnostic dilemma. In the past, preoperative diagnosis of gastric duplications was the exception, but with advances in imaging, most importantly endoscopic ultrasound, the diagnosis is established before surgery in a majority of the cases. Gastric duplication cysts have been removed using various methods; however, as enucleation can be performed easily with little disruption of normal anatomy, it should be considered the procedure of choice.

Abdominal Pain↗

PubMed2006

[Severe respiratory distress due to ileal duplication cyst in the newborn].

Differential diagnosis of neonatal respiratory distress includes pulmonary and systemic disorders and anatomic problems compromising respiratory system. We report on a 2770-g female born to a 29-year-old gravida 3, para 2 woman after 34 weeks of gestation. Antenatal ultrasound performed in week 8 and 21 was normal. The infant was delivered by cesarean section after amniotic membranes had been ruptured for less than 12 hours due to signs of fetal distress. The Apgar score was 3 and 3 at 1 and 5 minutes, respectively. The infant was intubated and resuscitated, and transferred immediately to the neonatal intensive care unit. She had an extremely protuberant and cyanotic abdomen. Dilated cutaneous collateral vessels were apparent in the periumbilical region. Abdominal sonography showed cystic multiloculated tumorous mass filled with dense, flocculent content at the level of hepatic portal. The tumorous mass occupied the majority of the abdomen with caudal extension toward the pelvis and dorsally toward the spine. The liver was displaced high under the diaphragm with the left liver lobe in the left hemiabdomen. On x-ray the lung were collapsed due to a large abdominal mass in the right hemiabdomen that displaced the right diaphragm and intestines contralaterally. She soon developed bilateral pneumothoraces. Drainage and continuous suction were started. The infant failed to improve despite all attempts and died. On autopsy, an extremely large, mobile, multichambered, solitary cyst was found. It was attached to the mesenteric side of the ileum by its own thin peduncular stalk and had no communication with the remainder of the gut. It occupied the majority of the abdomen. Histologic section revealed a well-developed smooth muscle wall and inner mucosa of small bowel type. Respiratory distress is a common problem in premature infants. The majority of cases are due to pulmonary disorders (e. g., hyaline membrane disease, meconium aspiration syndrome, pneumonia), hypothermia, metabolic acidosis, anemia, and congenital heart disease. Anatomic problems including space occupying lesions are less common. Duplications of the alimentary tract in infants and children are rare congenital anomalies. Although symptoms can occur at any age, they usually present during the first year. In our patient, intraabdominal mass caused severe respiratory distress and respiratory failure in the first hours of postnatal life. This had been seen before only as a complication of intrathoracic lesions extending into the abdominal cavity. Pathology revealed spherical intestinal duplication that was completely separated from the alimentary tract. Embryologically, it was a localized duplication. Respiratory distress in our patient was refractory to all means of mechanical ventilation. Poor lung compliance was the consequence of prenatal lung hypoplasia and inadequate postnatal lung expansion due to the duplication cyst space occupying character and its compressive effect. Prenatal diagnosis was the child's only chance for survival but it was not made. Duplications of the alimentary tract can present a diagnostic challenge even in the first hours of life. They should be included in the differential diagnosis of severe respiratory distress, especially in premature infants in which timely prenatal diagnosis cannot be always made. We propose their inclusion among other space occupying lesions that might be the cause of severe respiratory distress even in the earliest neonatal period.

Diagnosis, Differential↗

PubMed1991

[Gastroduodenal duplication and chronic hepatitis: fortuitous association?].

Gastroduodenal duplication is a rare congenital entity. Preoperative diagnosis is difficult because symptoms are usually non specific and can mimick pancreatitis. We report 2 cases of gastric and duodenal cystic duplication in adults presenting as pancreatitis. Chronic pancreatitis was observed on endoscopic retrograde pancreatography and confirmed at laparotomy in both cases. Pancreatitis was probably related to alcoholism in one case, but might have been secondary to duplication in the other. In both cases, duplication was misinterpreted initially as a pseudocystic complication of pancreatitis until laparotomy was performed. These 2 cases lead us to discuss the relationship between duplication and pancreatitis.

Adult↗

PubMed1990

Tubular colonic duplication: report of two cases.

Colonic duplication is a rare congenital abnormality frequently associated with multisystemic malformations. Colonic duplication presents diagnostic and therapeutic difficulties especially in neonates. We report on two patients, a child and an adult with tubular duplication. Treatment consisted of using the duplicated loop for a pull-through procedure in the first patient and resection of the duplicated loop in the second. The results of the surgical treatment in these two patients have been satisfactory.

Adult↗