Search PubMed⌕ Search

Biomedical subjects

D Y Graham

Publications and source records attributed to D Y Graham.

At least 559 records · Page 31Linked to original sources
PubMed1981

Endoscopic upper gastrointestinal polypectomy. Report of 73 polypectomies in 63 patients.

Seventy-three upper gastrointestinal endoscopic polypectomies were performed in 63 patients over a period of five years. Thiry-eight patients (52%) had adenomatous polyps, two of which contained carcinoma in situ and 26 (36%) were inflammatory in nature. Four lesions were removed from the duodenum. Hemodynamically significant hemorrhage occurred in five cases and persistent symptomatic ulcer in three cases. All complications occurred early in the series and responded to conservative measures. There was no mortality or need for surgical intervention in any case. It was concluded that: 1. upper gastrointestinal tract endoscopic polypectomy is a safe and relatively simple procedure; 2. postprocedural complications can be markedly reduced by prophylactic conservative antiulcer therapy and 3. especially in the area of adenomatous polyps, excision of the entire lesion is superior to biopsy in the detection of early malignancy.

Adenoma↗
PubMed1980

Limited value of early endoscopy in the management of acute upper gastrointestinal bleeding. Prospective controlled trial.

In an 11 month period, 95 patients with acute upper gastrointestinal hemorrhage underwent early fiberoptic endoscopy. Patients were randomized into two groups before endoscopy depending on whether the results of the procedure were revealed immediately or after 4 days. No attempt was made to influence the treatment or diagnostic plan. The groups were comparable with respect to historical features surrounding the bleeding episode and the anatomic site of hemorrhage. There were no significant differences in any aspect of patient management or outcome between groups. Important changes in diagnostic or treatment plan were made after learning the results of endoscopy in only 12% of the patients, half of whom were bleeding briskly at the time of endoscopy. It is concluded that the natural history of acute upper gastrointestinal hemorrhage (for example, the spontaneous cessation of bleeding) precludes endoscopy from having a significant effect on patient management.

Adolescent↗
PubMed1980

Ultrastructural study of rotavirus replication in cultured cells.

A systematic ultrastructural analysis of the replication cycle of the simian rotavirus SA11 in permissive MA104 cells was performed under reproducible conditions. At 8 h p.i., small areas of viroplasm were seen adjacent to swollen vesicles of the rough endoplasmic reticulum (rer) containing a few 80 to 90 nm virus particles. At later times, the size and number of these inclusions increased and the rer contained large numbers of the 80 to 90 nm particles as well as 52 to 65 nm particles. Infected cells eventually lysed, releasing progeny virus. Other cytological alterations included virus particles sequestered in lysosome-like bodies, 15 to 20 nm tubular structures in the nucleus and/or cytoplasm, convoluted membranes within the rer, filament bundles associated with virus particles, and mitochondria containing 1 to 5 virus particles. In addition, SA11 replication was studied in several less permissive cell lines. The results were similar to those with MA104 cells except that a smaller percentage of the cells were productively infected.

Animals↗
PubMed1980

In vitro transcription and translation of simian rotavirus SA11 gene products.

Rotavirus gene products were examined, with the simian rotavirus SA11 as a model. The endogenous viral RNA-dependent RNA polymerase associated with single-shelled virus particles or with activated double-shelled particles was used to synthesize viral RNA transcripts. Sedimentation velocity sucrose gradient analysis of the RNA transcripts revealed four peaks at 9S, 12S, 14S, and 18S, whereas agarose gel electrophoresis under partially denaturing conditions revealed eight groups of RNA species ranging in molecular weight from 2 x 10(5) to 1.2 x 10(6). The transcripts synthesized in vitro were active in an mRNA-dependent cell-free translation system derived from rabbit reticulocytes. The transcripts directed the synthesis of 11 polypeptides that had molecular weights ranging from 125,000 to 20,000 when analyzed by electrophoresis in sodium dodecyl sulfate-polyacrylamide gels. The products of in vitro translation were compared with polypeptides from purified virus and those synthesized in infected cells. Several of the polypeptides synthesized in vitro were designated as structural polypeptides by comparing the molecular weights determined by polyacrylamide gel electrophoresis analysis or by precipitation with hyperimmune serum prepared against purified virus. Three of the viral structural polypeptides (VP4, -5, and -5a) were not synthesized in vitro as primary gene products, demonstrating that processing must occur for the production of some structural polypeptides. Other in vitro-synthesized polypeptides were tentatively identified as either precursors to the viral glycoproteins or nonstructural polypeptides.

Centrifugation, Density Gradient↗
PubMed1980

Angiotherapy with Mallory-Weiss tear.

Most patients with upper gastrointestinal hemorrhage from Mallory-Weiss tear cease bleeding spontaneously and do not require specific therapy. Patients who either continue to bleed and those who rebleed represent specific therapeutic problems. Angiotherapy, either intraarterial vasopressin infusion (13 cases) or arterial embolization (two cases), was used to treat 15 patients with persistently bleeding Mallory-Weiss tears. Permanent hemostasis was achieved in the majority of patients treated. Results from the current study are compared with those previously reported in the literature. In addition the complications of each treatment method are discussed with emphasis on the cardiac complications of vasopressin.

Adolescent↗
PubMed1980

Identification of rotaviruses of different origins by the plaque-reduction test.

The plaque assay for the simian rotavirus SA11 was shown to be applicable to the economically important calf and porcine rotaviruses. In addition, neutralization of viral infectivity with specific antiserum before assay (plaque-reduction test) was found to be a useful test to identify the species of origin of rotaviruses.

Animals↗
PubMed1979

An enteric-coated pancreatic enzyme preparation that works.

A new enteric-coated pancreatic enzyme preparation (microspheres) was compared with traditional enzyme tablets in six subjects with severe exocrine pancreatic insufficiency. The microspheres were found to be as effective as traditional enzyme supplements. In most patients in balance studies, the lowest fecal fat values were obtained with microsphere therapy in spite of a smaller amount of lipase administered (6015 vs 10,800-43,200 lipase units per meal). In contrast to enteric-coated tablets, microspheres can be recommended in the treatment of pancreatic steatorrhea.

Adult↗
PubMed1979

Epidemic viral gastroenteritis.

Epidemic viral gastroenteritis is a significant world wide problem. In developed countries, gastroenteritis accounts for significant morbidity and loss of time from work; in the Third World it is the leading cause of mortality among infants and children. Recent technologic advances have been associated with an explosion of research activity. Two virus groups, the Norwalk-like agents and the rotaviruses, are currently accepted as causative agents of viral gastroenteritis in man. The problem of viral gastroenteritis is reviewed both from a current and a historic perspective.

Adult↗
PubMed1979

Corrosive injury to the stomach: the natural history and role of fiberoptic endoscopy.

Most physicians recognize that the ingestion of lye is associated with severe esophageal damage. It is much less widely known that gastric injury is the predominant finding when acid is ingested. We are reporting on five patients who had severe gastric damage after ingestion of diluted sulfuric acid (three cases), capsules of potassium hydroxide, and Clinitest tablets (one case each). Fiberoptic endoscopy was used to localize the extent and severity of injury and to follow the evolution of the damage. The extent and location of injury varied with the amount and type of agent ingested. Acid ingestion resulted in severe gastritis, which eventually led to antral stenosis and gastric outlet obstruction requiring operative intervention in two cases. Potassium hydroxide capsules produced diffuse esophagitis, gastritis, and a non-healing large gastric ulcer. Clinitest tablets produced distal esophagitis and stricture and antral damage leading to gastric outlet obstruction which required operative intervention. These cases demonstrate the natural history of corrosive injury to the stomach and the value of fiberoptic endoscopy in the management of this problem.

Acids↗
PubMed1979

Rotavirus stability and inactivation.

The stability of the infectivity of Simian rotavirus, SA11, has been analysed and compared to the stability of reovirus type 1. SA11 infectivity was stable to freeze-thawing, sonication, incubation at 25 degrees C overnight or at 37 degrees C for 1 h and to treatment with acid, ether, chloroform and Genetron. In contrast to reovirus, the infectivity of SA11 was more rapidly inactivated by heating at 50 degrees C. SA11 infectivity was inactivated above pH 10.0 and by heating at 50 degrees C in 2 M-MgCl2, but was stabilized by heating in 2 m-MgSO4; reovirus 1 infectivity was enhanced by heating in MgCl2. Both SA11 and reovirus 1 were inactivated by freezing in MgCl2. These results show that rotaviruses and reoviruses can be distinguished by their patterns of inactivation by physical and chemical agents.

Animals↗
PubMed1979

A plaque assay for the simian rotavirus SAII.

A sensitive, quantitative and reproducible plaque assay for the measurement of the simian rotavirus SAII is described. Plaque formation required the presence of the facilitators pancreatin or trypsin and diethylaminoethyl-dextran in the agar overlay. SAII produced plaques in three continuous primate cell lines: MA-104, CV-1 and LLC-MK2. MA-104 cells were the most sensitive.

Animals↗
PubMed1979

Comparison of methods for immunocytochemical detection of rotavirus infections.

Rotavirus infections in intestinal tissues of animals or in tissue culture cells were detected by the immunocytochemical unlabeled soluble enzyme peroxidase antiperoxidase method. Comparison of the immunofluorescence and peroxidase antiperoxidase immunological staining techniques revealed that the two methods are equally sensitive for detection of rotavirus-infected cells. The peroxidase antiperoxidase technique offers the advantages of negligible nonspecific staining reactions, the use of a standard light microscope, the production of permanent slides, and the conservation of immunological reagents. The ability to detect antigens in paraffin-embedded tissues enhances the usefulness of the peroxidase antiperoxidase test for both prospective and retrospective studies.

Animals↗