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Biomedical subjects

M Burrell

Publications and source records attributed to M Burrell.

At least 37 records · Page 2Linked to original sources
PubMed1991

Expression of an antisense viral gene in transgenic tobacco confers resistance to the DNA virus tomato golden mosaic virus.

Transgenic tobacco plants carrying a genetic cassette including an antisense DNA sequence of the virally encoded AL1 gene of the geminivirus tomato golden mosaic virus (TGMV) were constructed; AL1 encodes a protein absolutely required for TGMV DNA replication. These genetic cassettes also contained, on the same transcription unit, a gene encoding hygromycin resistance, which allowed selection for concomitant expression of the antisense gene. In transgenic lines, RNA transcripts of the predicted size and strand specificity were detected in antisense plants and sense controls. After infection of plants with TGMV, by agroinoculation, the frequency of symptom development was very significantly reduced in a number of antisense lines and correlated, broadly, with the abundance of antisense RNA transcript and with a reduction in viral DNA harvested from infected leaf tissue. We used an in vitro assay to study viral DNA replication in the absence of cell-to-cell spread; no replication was seen in five of the six antisense lines studied, in contrast to controls.

DNA Viruses↗
PubMed1991

Classic and vigorous achalasia: a comparison of manometric, radiographic, and clinical findings.

Compared with classic achalasia, vigorous achalasia has been defined as achalasia with relatively high esophageal contraction amplitudes, often with minimal esophageal dilation and prominent tertiary contractions on radiographs, and with the presence of chest pain. However, no study using current manometric techniques has compared manometric, radiographic, and clinical findings in vigorous and classic achalasia or questioned the usefulness of making this distinction. Fifty-four cases involving patients with achalasia whose radiographic and manometric studies were performed within 6 months of each other were available for review. Patients with vigorous achalasia (n = 17), defined by amplitude greater than or equal to 37 mm Hg, and patients with classic achalasia (n = 37), defined as amplitude less than 37 mm Hg, had substantial overlap in radiographic parameters of esophageal dilation, tortuosity, and tertiary contractions. Manometric properties of repetitive waves and lower esophageal sphincter pressure and clinical aspects of chest pain, dysphagia, heartburn, and satisfactory responses to pneumatic dilation were similar in both forms of achalasia. A separate analysis of patients with mean contraction amplitude greater than 60 mm Hg revealed similar findings. It is concluded that use of amplitude as a criterion for classifying achalasia is arbitrary and of dubious value.

Adult↗
PubMed1989

Recurrent cholangitis secondary to oriental cholangiohepatitis.

A Korean woman with a known mass in the left lobe of the liver and a normal gallbladder by ultrasound suffered recurrent cholangitis, which ultimately proved to be Oriental cholangiohepatitis. This disease, endemic to East Asia, has become widespread in the United States as immigration from that area has increased. The symptoms are identical to recurrent cholangitis associated with gallstones, but the natural history and definitive treatment are entirely different. The diagnosis should be suspected in patients with a history of parasitic infestation with Ascaris lumbricoides or Clonorchis sinensis or in those who have lived in an endemic area.

Adult↗
PubMed1988

The forgotten surgical foreign body.

Instruments and drains left in the abdomen following surgery may be responsible for bizarre and varied complications. The patient may remain asymptomatic for months or even years. Complications include adhesion formation, intestinal obstruction, abscesses, and erosion into the gastrointestinal tract. We report 3 patients in whom retained surgical material eroded into the duodenum and colon, respectively, and produced unusual radiologic findings and complications.

Adult↗
PubMed1983

Ureterosigmoidostomy: the development of tumors, diagnosis, and pitfalls.

The development of colon carcinoma after ureterosigmoidostomy has not received adequate attention in the radiologic literature. Two patients who had ureterosigmoidostomy and subsequently developed tumors are described. The third case is a patient with a ureterosigmoidostomy and a ureterocele that simulated the appearance of carcinoma in the sigmoid colon. This is the first report of this entity. Ureterosigmoidostomy patients need frequent follow-up studies since their incidence of carcinoma is significant. The use of barium to study the colon in this group of patients is controversial. Barium can potentially reflux into the kidney with fecal material, which can lead to fibrosis and impaired renal function. However, barium reflux up the ureter is usually of no significance except on those rare occasions when intrarenal reflux occurs and inflammatory changes may develop. The diagnosis of tumors in these patients, diagnostic pitfalls, and controversy regarding use of barium enemas in following these patients are discussed.

Adult↗
PubMed1982

Biliary tract abnormalities in patients with arteriohepatic dysplasia.

Arteriohepatic dysplasia is a congenital syndrome associated with life-long cholestasis. Because of symptoms suggesting extrahepatic biliary tract obstruction, we studied three patients with this syndrome by endoscopic retrograde cholangiopancreatogram (ERCP). All patients showed a decrease in the number of intrahepatic ducts. In addition, the intrahepatic ducts show attenuation with focal areas of dilatation. In one subject, this latter finding appeared to be a localized process. The extrahepatic ducts were also narrowed. One patient in this series was found to have gallstones and another cirrhosis. Although the relationship of these anomalies to the cholestasis seen in these patients is unclear, arteriohepatic dysplasis can be added to the list of processes associated with biliary tract abnormalities.

Adolescent↗
PubMed1981

Tc-99m HIDA scintigraphy in segmental biliary obstruction.

Segmental biliary obstruction as a result of primary or secondary hepatic malignancy has been reported with increasing frequency. For two representative patients, the clinical and Tc-99m HIDA scintigraphic findings in segmental biliary obstruction are described. The presence of photon-deficient dilated bile ducts in one segment of the biliary tree is highly suggestive of localized biliary obstruction and should be considered in the patient with suspected or proven hepatic malignancy despite the absence of jaundice.

Adenocarcinoma↗
PubMed1980

Roentgen manifestations of carcinoma in the gastric remnant.

Awareness of the increased incidence of carcinoma in the gastric remnant has not been accompanied by improved diagnosis or prolonged survival. The long latent period prior to development of tumor, the insidious nature of symptoms, and the anatomical distortion produced by surgery contribute to the difficulty in detection of these lesions. The radiological spectrum of carcinoma of the gastric remnant is discussed and both characteristic and unique radiographic features are illustrated.

Adenocarcinoma↗
PubMed1980

Myxedema megacolon.

The radiological findings on barium enema examination of 239 patients with thyroid deficiency (192 hypothyroid and 47 myxedematous) were reviewed. A new radiologic finding of transverse ridging superimposed on megacolon is described in myxedema and an explanation for this finding is postulated. The colonic findings associated with thyroid deficiency are presented.

Aged↗
PubMed1980

Cholangitis in a child due to biliary tract anomalies.

A 29-month-old child with persistent cholangitis and steatorrhea complicating congenital hepatic fibrosis underwent radiographic evaluation of the biliary tree. Communicating intrahepatic cavernous ectasias were demonstrated by percutaneous transhepatic cholangiography, a procedure deemed safe in children of this age group. Unlike most patients with cholangitis, he had documented steatorrhea and growth failure which resolved following successful treatment with trimethoprim-sulfamethoxazole. Bacteriologic diagnosis was made by direct culture of liver tissue combined with duodenal intubation.

Bile Ducts, Intrahepatic↗
PubMed1980

Aphthoid ulcerations in gastric candidiasis.

Tiny aphthoid erosions appear to represent the earliest detectable radiographic change in gastric candidiasis. In this report, the radiographic appearance of these lesions is correlated with gross and microscopic pathologic anatomy, and the progression of these ulcerations to deeper linear furrows is illustrated. It is hoped that the detection of the gastric candidiasis at this early stage will hasten therapy, and thus decrease the risk of fulminant infection in the immunocompromised host.

Adult↗
PubMed1980

Liquefactive necrosis of the pancreas: the pancreatic sac.

The authors describe an unusual form of pancreatic necrosis in which the excavated necrotic core is surrounded by a shell of tissue and forms a sac which generally conforms to the axis and contour of the pancreas. This debris-containing sac could be misinterpreted on ultrasound and CT and is best defined by direct injection into the pancreatic duct.

Adult↗
PubMed1979

Diagnosis of annular pancreas with endoscopic retrograde cholangiopancreatography.

Two patients with annular pancreas are described. The diagnosis was established unequivocally with endoscopic retrograde cholangiopancreatography before operation. In both patients there was pancreatitis of the annular pancreas. The first patient also had congenital absence of the ventral pancreas and pancreatic insufficiency. The second patient subsequently developed gastric outlet obstruction. The literature is reviewed.

Adult↗
PubMed1979

Transient hypertrophic gastropathy in childhood: a protein-losing gastropathy distinct from Menetrier's disease.

Transient hypertrophic gastropathy in a child with similarity of radiographic and clinical features to Menetrier's disease is described. Distinction from Menetrier's disease is emphasized as the condition is characterized by abrupt onset, short duration, eosinophila and good prognosis. The association with hypersensitivity as a possible etiology is more suggestive in this condition. The radiographic changes will often provide the first clue to this condition and rapid reversal of the gastric changes is diagnostic.

Child, Preschool↗
PubMed1977

Drug-induced gastrointestinal disease.

The gastrointestinal tract is a common target for adverse drug reactions. The resultant changes are often nonspecific (e.g., mucosal ulceration, intestinal infarction, motility disturbance) and in many cases no radiographically detectable lesion may occur. A comprehensive review of the reported drug-induced disorders of the digestive organs is herein presented and their radiographic manifestations are described.

Adult↗
PubMed1977

Iatrogenic problems following gastric surgery.

It is difficult to truly define iatrogenic complications in the postsurgical state in that the surgery is a condition originated by physician intervention and thus any problems that occur may be technically considered as physician created. In this article we attempt to demonstrate problems that occur both due to technical errors and the choice of operative procedure. In addition, unusual postsurgical anatomy is illustrated with the hope of avoiding further iatrogenic problems from lack of recognition.

Afferent Loop Syndrome↗